Microimaging Hardware Installation
Contents
1. Figure 7 Air Flow Diagram 5 When the gradient coil is installed connect it to both J806 inside the junction unit and to the 15 pin D shell J802 mounted to the outside of the junction unit Installing the Air Cooling System The gradient coil set and the microimaging probe use air for cooling The air flow diagram in Figure 7 shows the required connections Depending on the air flow requirements of the gradient coil set the pressure sensor switch S801 and S802 accordingly 20 UNITY NOVA Microimaging Hardware Installation 01 999070 00 A0499 UNITVINOVA Microimaging Module Installing the Preamplifier Attenuator This procedure describes how to install the preamplifier attenuator which attenuates the output of the observe preamplifier before the signal reaches the single mixer 1 Position the preamplifier attenuator 00 969935 00 on the floor near the magnet leg 2 Disconnect cable 00 958298 08 from the observe preamplifier output J5312 and connect it to the preamplifier attenuator output 3 Use cable 00 958298 03 to attach the preamplifier attenuator input to the observe preamplifier output J5312 Installing Gradient Coils and the Microimaging Probe Refer to the NMR Probes Installation Manual for the following procedures e Installing gradient coils e Inserting a sample into the microimaging probe e Installing and connecting the microimaging probe Configuring VNMR for Microimaging The microimagin2. Microimaging Hardware Installation UNITY NOVA NMR Spectrometer Systems Pub No 01 999070 00 Rev A0499 ap ms VARIAN Microimaging Hardware Installation UNITYTNOVA NMR Spectrometer Systems Pub No 01 999070 00 Rev A0499 Revision history A0499 Initial release Applicability of manual Microimaging module installed on UNITYTNOVA NMR spectrometer systems Technical contributors Simon Chu Tim Luca Emil Johnson Technical writers Mike Carlisle Daniel Steele Technical editor James Welch Copyright 1999 by Varian Inc 3120 Hansen Way Palo Alto California 94304 http www varianinc com All rights reserved Printed in the United States The information in this document has been carefully checked and is believed to be entirely reliable However no responsibility is assumed for inaccuracies Statements in this document are not intended to create any warranty expressed or implied Specifications and performance characteristics of the software described in this manual may be changed at any time without notice Varian reserves the right to make changes in any products herein to improve reliability function or design Varian does not assume any liability arising out of the application or use of any product or circuit described herein neither does it convey any license under its patent rights nor the rights of others Inclusion in this document does not imply that any particular feature is standard on the instru
3. semen 21 Tabiled4 Amplifier Faults c cc seescsccsacevceecastentscesscaveostentestvecedenevecueectassvacedeaeseatescdossdecetansaoatene 28 Table 5 Gradient System Faults isisisi asiaa iaaa 29 4 UNITVINOVA Microimaging Hardware Installation 01 999070 00 A0499 SAFETY PRECAUTIONS The following warning and caution notices illustrate the style used in Varian manuals for safety precaution notices and explain when each type is used WARNING Warningsare used when failure to observe instructions or precautions could result in injury or death to humans or animals or significant property damage CAUTION Cautions are used when failure to observe instructions could result in serious damage to equipment or loss of data Warning Notices Observe the following precautions during installation operation maintenance and repair of the instrument Failure to comply with these warnings or with specific warnings elsewhere in Varian manuals violates safety standards of design manufacture and intended use of the instrument Varian assumes no liability for customer failure to comply with these precautions WARNING Persons with implanted or attached medical devices such as pacemakers and prosthetic parts must remain outside the 5 gauss perimeter from the centerline of the magnet The superconducting magnet system generates strong magnetic fields that can affect operation of some cardiac pacemakers or harm implanted or attached devices such a
4. UNITYINOVA Microimaging Module e Configuring VNMR for Microimaging page 21 e Testing and Verifying the Gradient System page 22 e Calibrating and Configuring Gradient Strength page 23 The last section in this manual System Protection and Status page 27 describes the microimaging hardware Preparing for Installation Installing and testing the microimaging module requires the equipment listed below e Dual trace oscilloscope capable of accurate peak to peak voltage Vpp and measurements between 9 and 200 MHz Factory installations also require a digital oscilloscope with memory e 500 W 30 dB attenuator e Spectrum analyzer e Varian field service engineer tool kit Complete the following steps before installing the microimaging module 1 The microimaging cabinet see Figure 2 requires a three phase high current power source Verify that the main supply is 208 V 60 A 240 V 50 A 380 V 40 A or 415 V 30A and is separate from the 20 A power line to the UNIVINOVA console i Status panel nt p ATA j A X gradient amplifier 2 TINMIMMINMMMMI LT u p o crte URINA i if MNOM 1 Y gradient amplifier 9 TINMMMIMUMMMMTTT a s ee J o AMT d I 7 JMMMMUTHAUMM H 1 Z gradient amplifier o TINMMIMUMMMMMMMATTHMIT an Figure 2 Microimaging Cabinet with Gradient Control System Open Front View 1 0 UNITY INOVA Microimaging
5. to select the X channel Set gro 32767 d2 0 001 tpwr 0 pw 0 nt 1000 On the Smart DAC board s X test point you should measure 5 V for 2 ms Setting gro 32767 should result in a 5 V measurement and gro 0 should give a measurement of 0 V d Repeat steps a and b for the Y and Z gradients by changing orient ynn and then orient znn_ respectively 2 Test the shaped writer control path as follows a Enter rtp vnmr parlib gsh2pul1 to recall the gsh2pul parameter set b Setorient xnn gname hsine gro 32767 tpwr 0 pw 0 nt 1000 c Set tro 0 0005 i e 500 us Entering go should produce a one half sine wave at maximum of 5 V The pattern should be smooth and continuous Change t ro to tro 0 0100 i e 10 ms and enter go The pattern should still look smooth and continuous d Repeat steps a b and c for the Y and Z gradients using entering orient ynn for Y and orient znn for Z Testing the Gradient Compensation System Each gradient compensation unit X Y Z requires the following functional tests 1 Make sure the gradient amplifiers are either off or in standby 2 Enter the macro techron This recalls the compensation file named techron for Techron amplifier setup and sends it to the gradient compensation units Any SDAC duty cycle lights should be clear The status panel is either clear or blinking until manually reset 3 Enter gro 32767 dl 2 pw 0 tpwr 0 go You should see the following resul
6. 21 controls testing 22 current harness 20 interlock display 27 junction unit 29 status display 27 strengths 23 25 system faults 29 system testing 22 table creating 24 26 gradient waveform generator board installing 15 01 999070 00 A0499 Index H hardware description 9 29 installation 18 helium contact with body 6 helium gas flowmeters caution 8 high power amplifiers cautions 8 I imaging switch board 12 13 INPUT fault 28 installation preparation 10 installing microimaging hardware 12 21 J J UNIT fault 29 junction unit 19 L LED TEST button 29 M magnet quench warning 6 magnetic media caution 7 metal objects warning 5 microimaging cabinet installing 19 hardware installing 12 software 21 microimaging probe inserting a sample 21 installing and connecting 21 modifying the instrument 6 N nitrogen contact with body 6 nitrogen gas flowmeters caution 8 O observe preamplifier 21 OUTPUT fault 28 P pacemaker warning 5 power cables connecting 19 connecting 19 distribution unit 19 preamplifier attenuator 21 prosthetic parts warning 5 PTS frequencv svnthesizer installing 14 UNITVINOVA Microimaging Hardware Installation 31 Index R radio frequency emission regulations 8 READY LED 28 READY STANDBY switch 27 relief valves warning 7 removable quench tubes warning 7 RESET AMPS button 29 RESET button 28 RF pulse calibratio
7. Module Install the Connector board 01 904736 00 into the back of the two slots selected for the DECC and SDAC Line up the Connector board in the back of the card cage above two open P2 connectors Use the M2 5X8 screws provided 12 168209 00 The Connector board provides power to the DECC and SDAC boards and serves as the P1 connector upper in the card cage On the SDAC board set the J8 jumper to select current or voltage mode e Jumper J8 out BO driver is in current mode providing up to about 500 mA e Jumper J8 in BO driver is in voltage mode providing a voltage signal to an external current amplifier The BO driver circuit on the SDAC can provide up to about 500 mA of current For coils where this would not be enough drive an external amplifier is needed For an external amplifier the BO circuit provides a voltage signal to the external current amplifier Install the DECC and SDAC boards into the slots where the connector board has been installed The DECC board is on the left Installing the Gradient Waveform Generator Boards The Gradient Waveform Generator boards are installed in the rf control card cage 1 2 Locate the Gradient Waveform Generator boards 01 902034 xx Verify that their jumpers and switches are correct for their respective gradients See Table 1 Table 1 Gradient Waveform Generator Board Jumper Settings J u Gradient Gradient Gradient Gradient MEEL Channel X Channel Y Chan
8. RF Pulse Calibration File ss iss iss a tiesi iirissieusisrsinasuii ieies 25 Creating the Gradient Table isir skiet pe arpa EEEE EE EGE 26 System Protection and Status sssesennnnnnnnenennzznnnznnnzzznnzennnzznmnnnzznznnznz 27 LL a d A 31 01 999070 00 A0499 UNITY INOVA Microimaging Hardware Installation 3 List of Figures Figure 1 Microimaging System Layout ss nnnnnnnenzanennzzneznnznnnnnzanznnnnnanzznnznnanna za 9 Figure 2 Microimaging Cabinet with Gradient Control System Open Front View 10 Figure 3 RF Control Cardcage Front View Showing Slot Assignments 0 0 eee 14 Figure 4 UNITY TNOVA Microimaging Interconnect nn eennennenennnnnnnen nn 16 Figure 5 Voltage Regulator Module Installation ss eeennnnenennennn nanna 17 Figure 6 Self Test Jumper on DECC Board mens nenenn san n nn n antenna 18 Page 7 Air Flow Dia bt am ccisessssceclccescevisessenaces beeg beka es tent isa es get bala pet Zija oa POD abet 20 Figure 8 Gradient Interlocks and Status Display L eenennnenennenen ne nnennaa 27 Figure 9 Gradient Amplifier Front View top Back View bottom 28 Figure 10 Gradient Junction Unit Top View e nennnnenzneenznnnnnnnnnnnn nanna 29 List of Tables Table 1 Gradient Waveform Generator Board Jumper Settings L eee 15 Table 2 Microimaging Cabinet Power Connections se eennneneneznnznnenennnnne mezza 19 Table 3 Typical Microimaging Software Configuration File
9. STANDBY e Any fault will cause all enabled amplifiers to go into STANDBY e Press the LED TEST button to check that all indicator lights are functional e Ifthe DUTY CYCLE indicators are on do a setup from the decctool window to clear them e If any of the cables leading to J5 on the interlock board are not connected properly all the system fault lights will be on solid When powering up the gradient system the indicator lights may go into blinking mode You can remove this condition by pressing the RESET AMPS button on the status panel 01 999070 00 A0499 UNITYINOVA Microimaging Hardware Installation 29 UNITYINOVA Microimaging Module 30 UNITY NOVA Microimaging Hardware Installation 01 999070 00 A0499 A AC LINE fault 28 active fault 27 ACTIVE indicators 28 air cooling system installing 20 air flow 20 amplifier faults 28 automatic teller machine ATM cards caution 7 B blinking mode 29 C cables connecting 17 cautions defined 5 COIL faults 29 config command 21 connecting power 19 connector board 14 control paths testing 22 cooling air installation 20 COOLING fault 29 credit cards caution 7 D DECC accessory testing 18 DECC board installing 14 DUTY CYCLE indicators 29 DUTYCYC fault 28 E ecctool window 29 ENABLE DISABLE switch 27 F fault status light 27 field mapping 9 flammable gases warning 6 G gradient amplifiers 27 28 coils installing
10. cabinet The microimaging cabinet is powered by a 3 phase source separate from the power source for the rest of the UNTVINOVA system The Power Distribution Unit PDU is located at the bottom rear of the cabinet The PDU has a 15 foot cable that must be appropriately terminated in a 3 phase type connector to match the 3 phase power outlet provided by the user Table 2 lists the connectors and plug destinations Table 2 Microimaging Cabinet Power Connections Connectors Plug Destinations green ground G white neutral WwW black hot X orange hot Y red hot Z Make sure the circuit breaker switch on the PDU is off before the power source at the wall is connected and turned on CAUTION Make sure the voltage current ratings of the PDU match the ratings of the source A mismatch can cause electrical failure 1 Check in the microimaging cabinet that each gradient amplifier is connected to the three phase connectors of the PDU 2 Check to see that the card cage voltage selector at the rear power input module of the card cage is set to the proper single phase voltage corresponding to the voltage rating on the PDU Check that the card cage is connected with the power cord to the PDU Installing the Junction Unit and Gradient Harness 1 Place the junction unit 00 969930 00 near the magnet WARNING Make sure the ac power to the microimaging cabinet is OFF Disconnect the power cord from the microimaging cabinet Although safety c
11. centers the sample in the Z axis Creating the RF Pulse Calibration File From the previous results of the 90 pulse width create the RF pulse calibration file with the following command 01 999070 00 A0499 UNITYINOVA Microimaging Hardware Installation 25 UNITYINOVA Microimaging Module pulsecal name of coil pattern length flip angle power For example pulsecal rfcoill hard 75 90 55 This entry is saved into a text file called pulsecal in the vnmrsys directory Creating the Gradient Table 1 Enter creategtable and the following information Are all gradient axes calibrated to the same maximum value y n y Enter m for main coil h for HPAG coil o for other o Enter a name for gradient coil entry gcoill Enter a brief description of this gradient table Large imaging coil Enter the boresize in cm 10 Enter the maximum gradient strength gauss cm 30 Enter the risetime usec 100 The maximum gradient strength is the value from the specification 2 Join another experiment and enter sems to load the sems parameter set 3 Set the rfcoil parameter to the pulsecal file name and the gcoil parameter to the name of the gradient calibration coil that was set in step 1 e g rfcoil imaging coil gcoil gcoill 4 Set the following parameters thk 1 Slice of thickness in 1 mm lro 3 lpe 3 Field of view readout and phase encode to 3 cm pl 2000 p2 2000 2 ms pulse width plpat gauss Use Gaussian
12. power amplifiers with liquids probes On systems with solids high power amplifiers never operate the amplifiers with a liquids probe The high power available from these amplifiers will destroy liquids probes Use the appropriate high power probe with the high power amplifier CAUTION Take electrostatic discharge ESD precautions to avoid damage to sensitive electronic components Wear grounded antistatic wristband or equivalent before touching any parts inside the doors and covers of the spectrometer system Also take ESD precautions when working near the exposed cable connectors on the back of the console Radio Frequency Emission Regulations The covers on the instrument form a barrier to radio frequency rf energy Removing any of the covers or modifying the instrument may lead to increased susceptibility to rf interference within the instrument and may increase the rf energy transmitted by the instrument in violation of regulations covering rf emissions It is the operator s responsibility to maintain the instrument in a condition that does not violate rf emission requirements 8 UNITY NOVA Microimaging Hardware Installation 01 999070 00 A0499 UNITY INOVA Microimaging Module The UNITYINOVA microimaging module consists of a one phase continuous frequency synthesizer one rf waveform generator three gradient waveform generators three gradient amplifiers a linear rf preamplifier and the basic microimaging module The basic m
13. tables should help the operator determine the cause of a fault indication A steady nonblinking red light on any of the faults indicates that the fault is currently active and needs correcting A flashing red light indicates that the fault occurred previously but no longer exists The normal mode for turning on the power to the gradient amplifiers is as follows 1 Set the READY STANDBY switch on the front of each gradient amplifier to READY 2 Set the ENABLE DISABLE switch on the status display panel to DISABLE for each amplifier the yellow STANDBY LED will go on 3 Power on each amplifier with its circuit breaker rear of amplifier chassis 01 999070 00 A0499 UNITYINOVA Microimaging Hardware Installation 27 UNITYINOVA Microimaging Module Front View Cover Removed MASTER ml CROWN GGTA I OT100 INPUT Current Monito BOARD O T105 GND Output O O O T103 20 A V Tss B6 efee R117 OFFSET MANUAL READY OVER OVER RESET VOLTAGE O kd cl RUN STANDBY FAULT RESET Back View INPUTS INTERLOCK Power Distribution Box Input from Gradient Safety Interlock Board Compensation at bottom of cabinet Board Input Power Figure 9 Gradient Amplifier Front View top Back View bottom Table 4 Amplifier Faults Display Meaning OUTPUT Voltage to gradient coil is too high occurs when load is open INPUT Input from GCU is too high and gives too much power to the coil AC LINE I
14. A PART OF INOVA STANDARD SYSTEM NUM MICRO IMAGING SYSTEM INTERCONNECT Eo NOT OTHERWISE SPEC FRAG ANG SCALE FIN pece oe xe DATE S 31 107 D PP 1906047 A a Rew ory SHEETS rzi DRAWING NO REV 14 10 3 8 7 A 5 4 2 1 Figure 4 UNIVINOVA Microimaging Interconnect W VAONL inn Iewa ajnpoja bu UNITY INOVA Microimaging Module Installing the Voltage Regulator Module 1 Remove the blank panel from the back of the rf cabinet if necessary 2 Mount the voltage regulator module 01 905652 00 in the back of the rf cabinet as shown in Figure 5 Use the 10 screws nuts and washers 12 222060 08 14 122010 00 and 14 202010 00 RF cabinet Digital back cabinet i annnm Figure 5 Voltage Regulator Module Installation 3 Connect the following leads 15 to TB1001 7 e GND to TB1001 8 15 to TB1001 9 4 Connect the pigtail cable with the 16 pin white Molex connector from the voltage regulator module to the back of the Connector board Connecting the Cables The power and the gradient amplifier must still be off before connecting the cables as described in the steps below 1 Connect the mini DIN 8 patch cable 81 839724 00 between the DECC and the SDAC boards 2 Connect the ribbon cable 01 905517 00 to the gradient waveform generators to the SDAC and to the DECC 3 Connect J16 on the DECC boa
15. DECC board 2 Connect a jumper between pins 68 and 66 on the 68 pin condo connector on the DECC board as shown in Figure 6 DECC Ji ooj N e o o o o eee o o o o o fe o eeeeeee o o o o o ooo oo e o o o o o eee ee o o o oo e o o o o o o o o o o o e oo o oo i Figure 6 Self Test Jumper on DECC Board 3 Press the Reset button on the front of the DECC board This starts the self test A 10 Hz sine wave will be present at the DECC board outputs Measure the sine wave at the test points in the front of the board with an oscilloscope 1 8 UNITY INOVA Microimaging Hardware Installation 01 999070 00 A0499 UNITVINOVA Microimaging Module The LEDs also provide a visual indication of the 10 Hz wave When the jumper is removed or if the board is reset without the jumper present the board goes into normal mode waiting for the start of an experiment In this mode there should be a total of 6 LEDs on at the front of the DECC board When the power is on the 6 green power indicator LEDs on the front of the SDAC should be lit 4 After the test return the system to normal mode Remove the self test jumper that you connected in step 2 above See Figure 6 e Attach the ribbon cable to the DECC Connecting the Power The following procedures describe how to connect the power and signal cables to the microimaging
16. Hardware Installation 01 999070 00 A0499 UNITVINOVA Microimaging Module 2 Check the items in the shipping kit against the parts list provided in the kit If all the parts on the list are included in the kit proceed to the next step If anything is missing obtain it before proceeding WARNING CAUTION Equipment and tools used by the moving crew must be evaluated for safety in the magnetic field Install a plastic chain or chain of other nonmagnetic material at about 42 in 107 cm from the magnet body This serves as a reminder to prevent magnetic materials consoles for example from being pulled Into the magnet body Keep metal objects away from the magnet The strong magnetic field of the dewar attracts ferromagnetic objects such as compressed gas cylinders steel chairs steel carts and the microimaging cabinet Unless restrained such objects can strike the magnet causing extensive damage to the probe the dewar and the superconducting solenoid Use only nonferromagnetic materials such as plastics aluminum wood and stainless steel in the area around the magnet 3 Verify that there is enough room to accommodate the microimaging cabinet in the floor plan of the laboratory see the Installation Planning Guide The following are space guidelines a WARNING Measure the distance between the edge of the UNTWINOVA cabinet and the centerline of the magnet If this distance is greater than 185 cm 73 in and only
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18. and replace the shim supply back into the console 9 Reattach the shim coil cable to J908 of the Imaging Switch s metal bracket 10 Go to Connecting the Imaging Switch Board this page to connect the cables Imaging Switch Board Part No 01 903922 xx 1 Disconnect the power from the shim power supply and disconnect the shim coil cable 2 Carefully remove the shim power supply from the console 3 Remove the cover from the shim power supply In the rear of the supply are two D shell connectors J908 and J909 that are mounted to a removable plate 4 Remove the two screws fastening the plate to the rear wall of the shim supply and remove the plate Remove the 64 position pin ribbon cable connector from this plate 5 Connect the 64 pin ribbon cable connector into P907 of the Imaging Switch board 6 Mount the Imaging Switch board which has its own metal bracket inside the supply in the spot vacated by the removable plate 7 Replace the shim supply cover and replace the shim supply back into the console 8 Reattach the shim coil cable to J907 of the Imaging Switch s metal bracket 9 Goto Connecting the Imaging Switch Board this page to connect the cables Connecting the Imaging Switch Board 1 For Part No 01 993958 XX connect the Oxford room temperature shim coils to J908 of the Imaging Switch board J908 is located on the rear of the Varian shim supply For Part No 01 903922 XX connect the Oxford room temperature
19. ards are installed into the connector board 1 Remove the old DAC and GCU boards and the waveform generator cable if present 2 Choose two adjacent slots in which to install the DECC and SDAC Figure 3 shows the layout of the rf control card cage Ideally the DECC and the SDAC boards are installed next to the lock transceiver controller boards shown as A through F in Figure 3 note that on imaging systems if there is no DIFF AMP board installed the Lock Transceiver Controller board is not needed and slot 7 becomes a spare slot DECC SDAC spare slot WFG X WFG Y WFG Z Vy ABCDE F o 2 G o i G 5 s KA o 2 o a zT o i he ie ie w o kud 2 2 2 e o fl G o o o o o o E 2 S 85 sa ese a 6 o v o G c GE SG c GE 2 Ble O ZO O ES O s esososolsiolela 8 8 582 5 2 5 2 5 3 9 g o o o o o O 5 z lt 2 a ra L els Elola lE J ja o ed Slo elo SOS O 2 5 8 3E SJE SE SZ SE S lt al CZ EZ FB FS FA JE Slot Slot Slot Slot Slot Slot Slot Slot Slot Slot Slot Slot Slot Slot Slot Slot Slot Slot Slot Slot Slot 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 Figure 3 RF Control Cardcage Front View Showing Slot Assignments 14 UNITY INOVA Microimaging Hardware Installation 01 999070 00 A0499 UNITVINOVA Microimaging
20. ck of the shim power supply If there are three triax connectors X Y and Z1 the board is installed and you can skip to Installing the PTS Synthesizer with Overrange page 14 The Imaging Switch board disconnects the X Y and Z1 room temperature shim coils from the output of the Varian shim supply and connects the Varian outputs to the digital eddy current compensation DECC connector boards X Y and Z whenever the corresponding Techron gradient amplifier is enabled This enables X Y and Z1 shimming through the gradient coil set Imaging Switch Board Part No 01 993958 xx 1 Disconnect the power from the shim power supply and disconnect the shim coil cable 2 Carefully remove the shim power supply from the console 3 Remove the cover from the shim power supply 12 UNITYINOVA Microimaging Hardware Installation 01 999070 00 A0499 UNITY INOVA Microimaging Module In the rear of the supply are two D shell connectors J908 and J909 that are mounted to a removable plate 4 Remove the two screws fastening the plate to the rear wall of the shim supply and remove the plate Remove the two connectors from this plate 5 Connect the 37 pin D shell connector into J1 of the Imaging Switch board 6 Tiewrap the unused 9 pin D shell connector so it won t rattle around 7 Mount the Imaging Switch board which has its own metal bracket inside the supply in the spot vacated by the removable plate 8 Replace the shim supply cover
21. created in step 1 with the new gmax value calculated in the previous step Set gcoil and sysgcoil to the gradient coil name and enter imprep to reset gro gpe and other parameters in the sems experiment Obtain the image again and check the dimension of the cube image Repeat steps 8 through 13 until the dimension of the cube image is exactly 1 2 cm Calibrating Gradient Strengths ecctool 1 Set the gain setting in the ecctool to the appropriate gradient coil maximum specifications For example if the gradient coil has a maximum specification of 30 G cm at 50 amps at 20 duty cycle set the gain to 50 and the duty cycle to 20 or 15 to be on the safe side Create a file in the local directory vnmrsys imaging eddylib such as main with the X Y and Z gradients set to a gain of 50 and duty cycle of 15 Select setup in the ecctool window and execute a setup Place the cube in cube phantom into the coil approximately at the center of the Z axis Enter profile to load the profile parameter set If the parameter gradaxis is not present create it create gradaxis string gradaxis z Enter gzlvi1 8000 8000 Set pl to the 90 pulse and pw to the 180 pulse Set d1 1 d2 02 and tpwr to the appropriate level Enter ga and then dssa to obtain the two profiles You might need to set the attenuator box to 20 dB or 30 dB to avoid ADC overflow Adjust the length of the positioner until the two profiles coincide which
22. e rfcoil tothe pulsecal file name and set the gcoil to the name of the gradient calibration coil that was set in step 1 e g rfcoil imaging coil gcoil gcoill Set the following parameters thk 1 Slice of thickness in 1 mm lro 3 lpe 3 Field of view readout and phase encode to 3 cm pl 2000 p2 2000 2 ms pulse width plpat gauss Use Gaussian selective pulses p2pat gauss Enter imprep to set up the imaging pulse sequence 24 UNITY NOVA Microimaging Hardware Installation 01 999070 00 A0499 10 11 12 13 14 UNITVINOVA Microimaging Module Enter orient sag nv 0 grozgro gro dl 2 nt 1 ga to obtain readout profiles along Z direction Adjust the position of the sample up or down so that the two profiles coincide which centers the sample in the Z coil Enter orient trans nv 64 tr 1 go to obtain an image Transform the image with ft2d and rotate the sample positioner so that the image appears level Enter go to obtain another image Enter orient sag nv 128 ft2d to obtain an image and transform the data Set the two cursors at the edge of the square image in the F2 dimension Write down the value of delta in Hz Calculate the value of gro in DAC units as follows gro DACs gro G cm gmax G cm 32767 Enter setgcal to recalibrate gcal using the value of gro in DACs calculated above Note that the macro set gcal calculates gmax in G cm Enter creategtable which updates the gradient table file
23. elease of nitrogen and helium gasses from the dewar Therefore the magnet must be supported by at least one of two methods with ropes suspended from the ceiling or with the antivibration legs bolted to the floor Refer to the Installation Planning Manual for details WARNING Do not remove the relief valves on the vent tubes The relief valves prevent air from entering the nitrogen and helium vent tubes Air that enters the magnet contains moisture that can freeze causing blockage of the vent tubes and possibly extensive damage to the magnet It could also cause a sudden dangerous release of nitrogen and helium gases from the dewar Except when transferring nitrogen or helium be certain that the relief valves are secured on the vent tubes WARNING On magnets with removable quench tubes keep the tubes in place except during helium servicing On Varian 200 and 300 MHz 54 mm magnets only the dewar includes removable helium vent tubes If the magnet dewar should quench sudden appearance of gases from the top of the dewar and the vent tubes are not in place the helium gas would be partially vented sideways possibly injuring the skin and eyes of personnel beside the magnet During helium servicing when the tubes must be removed follow carefully the instructions and safety precautions given in the manual supplied with the magnet Caution Notices Observe the following precautions during installation operation maintenance and repair o
24. en in an enclosed space creating a possibility of asphyxiation Do not return until the oxygen level returns to normal WARNING Avoid helium or nitrogen contact with any part of the body In contact with the body helium and nitrogen can cause an injury similar to a burn Never place your head over the helium and nitrogen exit tubes on top of the magnet If helium or nitrogen contacts the body seek immediate medical attention especially if the skin is blistered or the eyes are affected WARNING Do not look down the upper barrel Unless the probe is removed from the magnet never look down the upper barrel You could be injured by the sample tube as it ejects pneumatically from the probe WARNING Do not exceed the boiling or freezing point of a sample during variable temperature experiments A sample tube subjected to a change in temperature can build up excessive pressure which can break the sample tube glass and cause injury by flying glass and toxic materials To avoid this hazard establish the freezing and boiling point of a sample before doing a variable temperature experiment 6 UNITY NOVA Microimaging Hardware Installation 01 999070 00 A0499 SAFETY PRECAUTIONS Warning Notices continued WARNING Support the magnet and prevent it from tipping over The magnet dewar has a high center of gravity and could tip over in an earthquake or after being struck by a large object injuring personnel and causing sudden dangerous r
25. f the instrument Failure to comply with these cautions or with specific cautions elsewhere in Varian manuals violates safety standards of design manufacture and intended use of the instrument Varian assumes no liability for customer failure to comply with these precautions CAUTION Keep magnetic media ATM and credit cards and watches outside the 5 gauss perimeter from the centerline of the magnet The strong magnetic field surrounding a superconducting magnet can erase magnetic media such as floppy disks and tapes The field can also damage the strip of magnetic media found on credit cards automatic teller machine ATM cards and similar plastic cards Many wrist and pocket watches are also susceptible to damage from intense magnetism Refer to the manuals supplied with the magnet for the size of a typical S gauss stray field This gauss level should be checked after the magnet is installed 01 999070 00 A0499 UNITVINOVA Microimaging Hardware Installation 7 SAFETY PRECAUTIONS Caution Notices continued CAUTION Check helium and nitrogen gas flowmeters daily Record the readings to establish the operating level The readings will vary somewhat because of changes in barometric pressure from weather fronts If the readings for either gas should change abruptly contact qualified maintenance personnel Failure to correct the cause of abnormal readings could result in extensive equipment damage CAUTION Never operate solids high
26. g software option can be installed at any time from the VNMR CD ROM Refer to the VNMR and Solaris Software Installation Manual for more information Run config to add gradients using Table 3 as a guide WFG SDAC refers to the waveform generator and the Smart DAC board Table 3 Typical Microimaging Software Configuration File Label Value RF Channel 1 Obs Type of RF Synthesizer Latching Frequency Overrange Frequency Step Size Coarse Attenuator Upper Limit Fine Attenuator Waveform Generator Type of Amplifier Axial Gradients X Axis Y Axis Z Axis 01 999070 00 A0499 U Direct Synthesis PTS 500 Present 100 000 0 1 Hz 79 63 dB Present Present Linear WEG SDAC WEG SDAC WEG 4 SDAC UNITV INOVA Microimaging Hardware Installation 21 UNITYINOVA Microimaging Module Testing and Verifying the Gradient System The following gradient system items are tested e Gradient controls e Gradient compensation system e Gradient coil assignments Testing Gradient Controls This procedure describes how to test the direct write and shaped write gradient control paths Perform gradient controls tests with the gradient amplifiers off or on standby Gradients are controlled through waveform generators 1 Test the direct write control path as follows Enter decctool and create a file b Enter rtp vnmr parlib gtest1 to recall the gtesti parameter set c Setorient xnn
27. ircuits exist to protect the user if the junction unit is opened it is highly advisable to work with the ac power off since the gradient amplifiers can put out lethal amounts of power 01 999070 00 A0499 UNITYINOVA Microimaging Hardware Installation 1 9 UNITYINOVA Microimaging Module CAUTION Do not connect the harness leads to COMMON This can cause excessive currents to flow through the gradient coil which might damage the coil if the in line fuses do not protect it properly 2 Connect the heavy gauge gradient current harness 00 990910 00 to TB1 of the junction unit Connect the other end of the gradient current harness to each of the gradient amplifiers For each amplifier the two harness leads should be connected to OUTPUT and SAMPLED COMMON A 2 7 ohm resistor must go between SAMPLED COMMON and the amplifier chassis make sure the chassis end is making good electrical contact The chassis must also make good contact to the side of the gradient current harness 3 Connect the 37 pin D shell cable 00 9909 14 20 from J741 on the rear of the microimaging cabinet to J801 of the junction unit 4 Check that the air hoses are properly connected See the air flow diagram in Figure 7 Probe Cooling A i Junction Unit f i 00 969930 00 Gradient Coil y i S801 S802 Pneumatics 00 991434 00 U PESK A
28. istance 01 999070 00 A0499 UNITY INOVA Microimaging Hardware Installation 5 SAFETY PRECAUTIONS Warning Notices continued Refer to the manuals supplied with the magnet for the size of a typical 10 gauss stray field This gauss level should be checked after the magnet is installed WARNING Only qualified maintenance personnel shall remove equipment covers or make internal adjustments Dangerous high voltages that can kill or injure exist inside the instrument Before working inside a cabinet turn off the main system power switch located on the back of the console WARNING Do not substitute parts or modify the instrument Any unauthorized modification could injure personnel or damage equipment and potentially terminate the warranty agreements and or service contract Written authorization approved by a Varian Inc product manager is required to implement any changes to the hardware of a Varian NMR spectrometer Maintain safety features by referring system service to a Varian service office WARNING Do not operate in the presence of flammable gases or fumes Operation with flammable gases or fumes present creates the risk of injury or death from toxic fumes explosion or fire WARNING Leave area immediately in the event of a magnet quench If the magnet dewar should quench sudden appearance of gasses from the top of the dewar leave the area immediately Sudden release of helium or nitrogen gases can rapidly displace oxyg
29. ment UNITYTNOVA MERCURY UNITYplus UNITY GEMINI 2000 Gemini GLIDE VXR XL VNMR VnmrS VnmrX Vnmrl VnmrV VnmrSGI MAGICAL AutoLock AutoShim AutoPhase limNET Ultraenmr Indirectenmr Autoenmr Tripleenmr MagicAngleenmr Protonenmr Bioprotonenmr ASM and SMS are registered trademarks or trademarks of Varian Inc OpenWindows Sun Solaris Suninstall SPARC and SPARC station are registered trademarks or trademarks of Sun Microsvstems Inc and SPARC Int Oxford is a registered trademark of Oxford Instruments LTD Ethernet is a registered trademark of Xerox Corporation Other product names in this document are registered trademarks or trademarks of their respective holders Table of Contents SAFETY PRECAUTIONS siiccansisisnssccsisscnttcanstacctasonsrieniieutsasaseistannidieidoisaernueats 5 UITYINOVA Microimaging Module ssssssceseseesesrssssenseseseesenseneenensenaees 9 Preparing for Installation s sies in ees 10 Installing Microimaging Hardware scccsssseecesseeeeeeesseneeeeesseeneesesseeeeenees 12 Installing the Imaging Switch Board io ccsccsccessesccisserecssepevbassspesessancseaveasasszsessantsaseseapsbes 12 Installing the PTS Synthesizer with Overrange nee en sens 14 Installing the Connector DECC and SDAC Boards e neeenn men enennen enti 14 Installing the Gradient Waveform Generator Boards Lee 15 Installing the Voltage Regulator Module scciesesuscasscescateesss este see tor so
30. n file calibrating and configuring 23 creating 25 S safety interlock board 27 safety precautions 5 7 sample inserting into microimaging probe 21 SDAC board installing 14 signal cables connecting 19 slot assignments rf control cardcage 14 solids high power amplifiers caution 8 STANDBY LED 27 T techron macro 22 TEMP fault 28 U upper barrel warning 6 V VME cardcage 9 VNMR configuring 21 voltage regulator module installing 17 VT experiment warning 6 W warnings defined 5 32 UNITY INOVA Microimaging Hardware Installation 01 999070 00 A0499
31. nel Z Channel W J2 1 2 1 2 1 2 1 2 J8 1 2 1 2 1 2 1 2 J9 1 2 1 2 1 2 1 2 J10 1 2 1 2 1 2 1 2 J17 1 2 1 2 1 2 1 2 J16 Not Used for Not Used for Not Used for Not Used for Gradients Gradients Gradients Gradients Switch 2 Gradients 3 Gradients 4 Gradients 5 Gradients SW 1 2 3 4 5 Insert the Gradient Waveform Generator boards into the nearest three spare slots to the right of the Smart DAC board with X being the closest to the Gradient DAC board Using the SMB cables that were used in the microimaging cabinet to provide 40 MHz to the Waveform Generator boards connect a 40 MHz clock from the Receiver Controller to each of the Waveform Generator boards Use an SMB T 58 180018 00 if not enough outputs are available See Figure 4 01 999070 00 A0499 UNITYINOVA Microimaging Hardware Installation 1 5 91 LOIJPJJEJSUJ asempsey DUIBELIOJJIJI VAONI ALINA 66 0V 00 0 0666 10 14 10 9 a 7 Vv Deon Basa NO TYPE Om MODEL NEXT ASSEMELY aa Pe te ip ee ee ee 7 So 7 i eee ee Ee l l i l G i i i RF CONTROL GRADIENT BAY i i t CAGE I i H i 3rd BAY i i 2nd BAY i i i 1 i H i i P J3 l u 1 i i i i i i i l i i i i 4 F i 1 1
32. neta desa dok 17 Connecting the Cables crisi reen rie e B A p pa Spa Job 17 Finishing the Hardware Installation 13103 vort svo ali ka bebkp eb FESTI ceusdneseostastesrnotbancssabesocnsees 18 Testos Tha WRC CoA Gee SS Oy cicir eee noona E p pi e A sp 18 Connecting MC PO WEL sci aids sinai i ip pis pi agape a sa f p 19 Installing the Junction Unit and Gradient Harness semen 19 Installing the Air Cooling Syster ss isesssesessiccsasevsessepevesaseascesvanssease p AT 20 Installing the Preamplifier Attenuator ic cc2 secs cess cecssecsccesteacaceacastanss cece thevadentscedee kk 21 Installing Gradient Coils and the Microimaging Probe seen 21 Configuring VNMR for Microimaging sserunnnazenzannannnnnzennnnnnanznnanzmnanmn nanna 21 Testing and Verifying the Gradient System sssseeennnzennnnnnnznnnnnzznnnneza 22 Testing Gradient Controls al A BR es 22 Testing the Gradient Compensation Systemi s s ccsessseensehscissacvscabssassessessessssepestiasdes 22 Calibrating and Configuring Gradient Strength ssesenenzannnzenznnnnzznnzzenzz 23 Creating the RF Pulse Calibration Fale ss iii sewint isch pk ra e res be swe oeer 23 Calibrating Gradient Strengths iscrisse tiatesedsvensasdissseeaseabtearesdaeseesdesdbestea sees 23 Creating the Gradient Tabi ise bi soon soneta seek eo toka ostanak Ero SAS bode pitate a Seta EE 24 Calibratirig Gradient Strengths ECCIOOL ss sse5 00 isir ien tejp geto va osa pol 25 Creating the
33. nput line voltage is too high by 10 or more TEMP Output transistors or amplifiers are too hot DUTYCYC Input from GCU is too high and gives too much power to the coil The duty cycle threshold value is set by the user from the ecctool window 4 Press the RESET button on the status panel If no faults occur the READY LED and all three ACTIVE indicators will light 28 UNITY NOVA Microimaging Hardware Installation 01 999070 00 A0499 UNITVINOVA Microimaging Module Gradient Cables Out an Hoses Qur 3 twisted pairs To Gradent Coil To Probe To Gradient Coils Interlock Signals In Themocouples Coil Out Switch Air Pressure Switches Junction Open Microswitch Air Pressure Guage I Latch Fuse Block 1 Gradient Cable in from J80 Ta Air H I Safety Interlock Board Gradient Amplifiers ir Hoses In Figure 10 Gradient Junction Unit Top View Table 5 Gradient System Faults Display Meaning COIL OPEN Load is open coils cables or fuses COIL HOT Thermocouples inside the coil measure a temperature over 75 C COIL OUT Gradient coil set is removed from the magnet bore J UNIT Interlock in the Gradient Junction Unit is not made cover open COOLING Pressure switches on Gradient Junction Unit indicate cooling air to gradient coils is not present Other operational considerations include e If the slide switch on the gradient amplifier is set to STANDBY the status panel will also read
34. odule is not frequency specific The basic module provides for rf and gradient waveform generation gradient signal conditioning gradient current drive amplification a safety interlock system All microimaging pulse sequence timing remains under master control of the pulse controller board The microimaging cabinet see Figure 1 for the microimaging module houses the safety interlock board three gradient amplifiers a power distribution unit and a gradient system status panel Micra Cabinet ang Figure 1 Microimaging System Layout The Varian microimaging module can be can be installed on Varian UNTWINOVA 300 or 400 MHz 89 mm vertical bore NMR spectrometer This module adds the X Y and Z gradient capabilities for microimaging experiments Many of the hardware and software operations and utilities of the liquids spectrometer particularly those involved with 2D NMR remain the same Field mapping of all magnets is recommended for good homogeneity over large volumes microimaging samples greater than 5 mm especially for systems with 23 or more RT shims coils Field mapping is sold separately Instructions for installing the microimaging module on UNTWINOVA NMR spectrometers is described in this manual The major installation steps are covered in the following sections e Preparing for Installation page 10 e Installing Microimaging Hardware page 12 01 999070 00 A0499 UNITY INOVA Microimaging Hardware Installation 9
35. rd to 40 MHz using the SMB Cable 00 992897 04 Use the SMB T adapter 58 180018 00 if necessary 4 Connect the twinax cables between the SDAC and the gradient amplifiers 5 Connect the BO output from the SDAC to the coil or external amplifier as appropriate 01 999070 00 A0499 UNITYINOVA Microimaging Hardware Installation 17 UNITYINOVA Microimaging Module 6 For systems in which the X Y and Z shim fields i e XI Y1 and Z1 are created from the gradient coils install the shim adapter cable 01 905516 00 The appropriate shim power supply in which the X Y and Z shim signals are voltage signals as opposed to current signals must be used e Connect the male end of the 37 pin D shell connector to the shim power supply e Connect the twinax breakout cables to the back of the Connector board e Connect the female end of the 37 pin D shell connector to the shims higher order Finishing the Hardware Installation Finish the hardware installation by turning on system power as described in the steps below 1 Turn on system power in the following order e Console main power RF and digital power on the front of the console 2 Switch on the gradient amplifiers and the shim power supply The hardware installation is complete To test the DECC accessory go to the next section Testing the DECC Accessory Test the DECC accessory using the steps in this section 1 Disconnect the ribbon cable 01 905517 00 from the
36. s prosthetic parts and metal blood vessel clips and clamps Pacemaker wearers should consult the user manual provided by the pacemaker manufacturer or contact the pacemaker manufacturer to determine the effect on a specific pacemaker Pacemaker wearers should also always notify their physician and discuss the health risks of being in proximity to magnetic fields Wearers of metal prosthetics and implants should contact their physician to determine if a danger exists Refer to the manuals supplied with the magnet for the size of a typical S gauss stray field This gauss level should be checked after the magnet is installed WARNING Keep metal objects outside the 10 gauss perimeter from the centerline of the magnet The strong magnetic field surrounding the magnet attracts objects containing steel iron or other ferromagnetic materials which includes most ordinary tools electronic equipment compressed gas cylinders steel chairs and steel carts Unless restrained such objects can suddenly fly towards the magnet causing possible personal injury and extensive damage to the probe dewar and superconducting solenoid The greater the mass of the object the more the magnet attracts the object Only nonferromagnetic materials plastics aluminum wood nonmagnetic stainless steel etc should be used in the area around the magnet If an object is stuck to the magnet surface and cannot easily be removed by hand contact Varian service for ass
37. selective pulses p2pat gauss 5 Enter imprep to set up the imaging sequence 6 Enter orient sag nv 1 grozgro gro dl 2 nt 1 and type ga to obtain readout profiles along the Z direction Adjust the position of the sample up or down so that the two profiles coincide which centers the sample in the Z coil 7 Enter orient trans nv 64 tr 1 and type go to obtain an image Transform the image with t2d and rotate the sample positioner so that the image appears level 8 Enterorient sag nv 128 to obtain an image Enter ft 2d to transform the data Set the two cursors at the edge of the square image in the F2 dimension Write down the value of delta in cm 9 Calculate the value of gain for the Z gradient in ecctool as follows Z gain new gain setting gain current setting in ecctool factor where factor is the ratio of the displayed size and the actual size of the cube Set the two cursors at the edge of the square image in the F1 dimension Write down the value of deltal in cm Calculate the value of gain for the X gradient Y gain new gain setting gain current setting in ecctool factor where factor is the ratio of the displayed size and the actual size of the cube 26 UNITYINOVA Microimaging Hardware Installation 01 999070 00 A0499 UNITVINOVA Microimaging Module 10 In ecctool save the new setting and load the file to the GCU and repeat step 8 until the displayed size in both dimensions is exactly 1 2 cm 11 Repeat s
38. shim coils to J907 of the Imaging Switch board J907 is located on the rear of the Varian shim supply 2 Connect the cable from J6 of the Safety Interlock board to J2 of the Imaging Switch board J2 is located on the rear of the Varian shim supply 3 Connect the three blue twinax cables from the DECC connector boards to the X Y and Z1 connectors of the Imaging Switch board The twinax connectors are located on the rear of the Varian shim supply 4 Make sure the power cable is connected 01 999070 00 A0499 UNITY INOVA Microimaging Hardware Installation 1 3 UNITYINOVA Microimaging Module Installing the PTS Synthesizer with Overrange This procedure describes how to install the PTS 500 frequency synthesizer with overrange Part No 00 990880 01 1 Remove power disconnect all cables and remove the connector board from the rear of the PTS unit in the UNTWINOVA NMR console Remove the PTS from the cabinet 2 Install the new PTS 500 unit in the vacant space Adjust the 10 MHz OUT of the PTS 500 to between 8 and 10 dB of signal 3 Connect the PTS Connector board 00 992106 00 to the PTS 500 Also install the overrange cable 00 993015 00 between the PTS 500 and PTS Connector board 4 Check the dip switch settings for overrange 5 Reconnect the coaxial cables to the PTS 500 Installing the Connector DECC and SDAC Boards The Connector board is installed into the back of the rf control card cage and the DECC and SDAC bo
39. sult In permanent damage to components Installing Microimaging Hardware The procedures in this section describe how to install the various parts of the microimaging hardware Be sure that you have completed Preparing for Installation page 10 before continuing with the installation This section contains the following procedures e Installing the Imaging Switch Board this page e Installing the PTS Synthesizer with Overrange page 14 e Installing the Connector DECC and SDAC Boards page 14 Installing the Gradient Waveform Generator Boards page 15 Installing the Voltage Regulator Module page 17 e Connecting the Cables page 17 Finishing the Hardware Installation page 18 Testing the DECC Accessory page 18 e Connecting the Power page 19 Installing the Junction Unit and Gradient Harness page 19 Installing the Air Cooling System page 20 Installing the Preamplifier Attenuator page 21 Installing Gradient Coils and the Microimaging Probe page 21 Installing the Imaging Switch Board There are two imaging switch boards e For systems with the Oxford ribbon cable style of room temperature shims the board to install in the shim supply is Part No 01 903922 xx e For systems with the Oxford red tube room temperature shims the board to install in the shim supply is Part No 00 993958 xx The installation procedure for each board is quite similar To verify whether the imaging switch board is installed look at the ba
40. teps 8 and 9 with orient cor and adjust the gain setting for X using F1 dimensions System Protection and Status The gradient system safety interlock board is located on the top side of the cabinet The safety interlock board interprets diagnostic information provided by the amplifiers and coil system via the junction unit and determines whether the gradient amplifiers should be enabled or disabled The safety interlock board also drives the shim switch unit and the gradient cabinet status panel see Figure 8 ENABLE ENABLE ENABLE READY DISABLE DISABLE DISABLE STANDBY ACTIVE ACTIVE ACTIVE GRAD OPEN STANDBY STANDBY stanpBy COL OUTPUT OUTPUT OUTPUT INPUT INPUT INPUT or reser avs AC LINE AC LINE AC LINE TEMP TEMP TEMP JUNIT LED TEST DUTYCYC DUTYCYC DUTYCYC COOLING Code for LEDs WARNING EMERGENCY Green Yellow SERVICE Red Figure 8 Gradient Interlocks and Status Display The purpose of the gradient interlock and status display is to prevent serious damage that could be caused by the high currents produced by the gradient amplifiers Additional protection and status is built into the gradient amplifiers see Figure 9 and the fuse block in the junction unit see Figure 10 WARNING Do not disable the gradient interlock The gradient amplifiers produce high currents that could result in serious injury or death Table 4 lists amplifier faults and Table 5 lists gradients system faults The information in these
41. the 90 pulse width calibration of the rf probe must have been determined Creating the RF Pulse Calibration File This procedure describes how to create the rf pulse calibration file e From previous results of the 90 pulse width use thepulsecal command to create the rf pulse calibration file as follows pulsecal name of coil pattern length flip angle power For example pulsecal rfcoill hard 75 90 55 This entry is saved into a text file called pulsecal in the vnmrsys directory Calibrating Gradient Strengths This procedure describes how to calibrate the strength of the Techron gradient amplifiers 1 Set the overall gain setting in the decctool window to the appropriate gradient coil maximum specifications e g if the gradient coil has a maximum specification of 30 G cm at 50 amps at 20 duty cycle set the overall gain to 50 and duty cycle to 20 or 15 to be on the safe side 2 Click save in the deccTool window 3 Place the cube in cube phantom into the coil approximately at the center of Z axis 01 999070 00 A0499 UNITYINOVA Microimaging Hardware Installation 23 UNITYINOVA Microimaging Module 10 Enter profile to load the profile parameter set If the gradaxis parameter does not exist create it create gradaxis string gradaxis z Enter gzlv11 8000 8000 d1 1 d2 0 02 Set pl to the 90 pulse pw to the 180 pulse and tpwr to the appropriate level Enter ga and then dssa to obtain the t
42. the microimaging cabinet is going to be installed then go on to step 6 If the distance is less than 185 cm 73 in determine how much distance must be added to accommodate the microimaging cabinet 185 cm measured additional distance needed 73 in distance Place the UNIVINOVA cabinet at the correct distance the left edge of the cabinet must be at least 48 inches away from the center of the magnet Disconnect all cables from the magnet leg and move them away from the right side of the console Only qualified maintenance personnel shall remove equipment covers or make internal adjustments Dangerous high voltages that can kill or injure exist inside the instrument Before working inside a cabinet turn off the main system power switch located on the back of the console 4 Shut down the system 5 Remove the power connector from the rear of the UNTINOVA cabinet CAUTION The following installation involves handling static sensitive equipment and printed circuit boards Take all precautions necessary to suppress electrostatic spikes and discharges near the devices stand on antistatic pads wear natural fiber materials and use a grounded antistatic wristband before touching any equipment etc Be especially careful with red colored boards These are extremely static 01 999070 00 A0499 UNITY NOVA Microimaging Hardware Installation 11 UNITYINOVA Microimaging Module sensitive Failure to suppress electrostatic discharges can re
43. ts on an oscilloscope e 5 V output at corresponding Gradient DAC output test point e no amplitudes associated with the time constants 22 UNITY NOVA Microimaging Hardware Installation 01 999070 00 A0499 UNITVINOVA Microimaging Module e 2 5 V 50 of 5 V output voltage at output test point on the corresponding SDAC O P board because gain was set to 50 e GCU duty cycle light blinking slowly depending on thresholds For each gradient in turn complete the following steps 1 Enter decctool to open the decctool window 2 With decctool set files to global and select techron from the scrolling list 3 Click the setup button 4 Set files to local select temp 5 Set the overall gain to 40 and the duty cycle to 80 for each gradient Click save With orient xnn for X orient ynn for Y or orient znn for Z you should see the following results from each gradient test point on the SDAC board e 2V 40 of 5 V e no duty cycle lights e no amplitudes associated with the time constants 6 Use decctool1 to set all amplitudes to 100 and repeat steps 2 to 5 above for each gradient A probe of all test points should show an exponential decay at the specified time constant 7 Reset the files to global select techron and click the setup button Calibrating and Configuring Gradient Strength Before the procedures in this section can be performed the gradient coils must have been properly matched to the amplifiers and
44. wo profiles You might need to set the attenuator box to 20 dB or 30 dB to avoid ADC overflow Adjust the length of the positioner until the two profiles coincide which centers the sample in the Z axis Display one of the profiles e g ds 1 and measure the width of the profile in Hz at 25 height at each end Enter setgcal and answer the following questions What is the size of the object cm 1 2 What is the frequency spread Hz 45500 What is the gradient value dac s 8000 Answer y to the value of gcal calculated by the setgcal macro If the maximum gradient strength calculated is less than the specified value of the gradient coil change the gain setting for the Z gradient in decctool and repeat steps 8 through 11 until the value is reached Write down the value of the maximum gradient strength which will be used in creating the gradient table Creating the Gradient Table 1 Enter creategtable and the following information Are all gradient axes calibrated to the same maximum value y n y Enter m for main coil h for HPAG coil o for other o Enter a name for gradient coil entry gcoill Enter a brief description of this gradient table Large imaging coil Enter the boresize in cm 10 Enter the maximum gradient strength gauss cm 30 Enter the risetime usec 100 The maximum gradient strength is the value from the specification Join another experiment and enter sems to load the sems parameter set Set th
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