Oz DIY-WB User's manual
Contents
1. Volts Removing the 8 pin sensor connector is a good way to test that the WB unit has power Oz DIY WB and 5301 Display P4 5301 Display Operational Requirements The 5301 display normally gets its power from the WB unit The DB9 male connector on the long cable uses just three pins for power ground and wideband signal If you closely inspect the connector itself you will identify the numbering there to determine which pin is which The power is applied to pin 9 Ground to pin 6 on the other side of the connector to pin 9 and the signal is on pin 7 beside pin 6 The 5301 display draws less than a tenth of an Amp in operation NTK LiH1 Sensor Honda Part 36531 P07 003 The wideband sensor measures AFR when used with the DIY WB interface by sensing the partial pressure of oxygen in the exhaust gas The L1H1 sensor is vital to the operation of the DIY WB unit and is made by NTK but is normally sold as an aftermarket part and may be packaged as a Bosch Echlin etc part The Parts Bin part C5010 75044 Napa Online part ECHOS791 Honda part 36531 P07 003 and others sell the sensor but due to the high demand are often out of stock Sensor Mounting The sensor screws into an 18 mm diameter hole with a pitch of 1 5 mm thread A 22 mm 7 8 spanner secures it into a standard oxygen sensor bung The sensor can often physically replace the existing oxygen sensor but for proper operation of the ECU it is often desira2. with a turbocharger should position the sensor after the turbo and before the cat as a high exhaust back pressure as will be found between the manifold and the turbo has an effect on the measured AFR and tends to read richer than is actually the case Sensor Life The sensor is rated for a life of 160 000 km 100 000 miles when used in an unleaded vehicle but can be quickly contaminated by lead and other compounds found in some racing fuels The sensor should never be left in an exhaust stream without power to the heater circuit as this will rapidly gum up the internal components with carbon that is otherwise burnt off at normal operational temperatures Ageing of the sensor tends to produce a slower response to changing AFRs and this is a way to qualitatively determine your sensors age Oz DIY WB and 5301 Display P5 It is recommended to shroud the sensor when using fuels that create high levels of particulate matter including lead and carbon in an attempt to prevent particles entering the sensor s diffusion chamber and thus blocking it and slowing its response Sensor calibration Calibration of individual sensors is not required as a calibration resistor Rcal in the image the resistor is hidden inside the connector housing is provided by the factory in each sensor s grey connector shell Two extra pins inside the cable to the sensor are used to connect Rcal to the WB unit It is possible to check the calibration of the
3. 0 1 000 14 70 6 40 14 50 2 50 Volts but can be as high as 2 53 and as low as 2 47 The figures presented here assume the calibration resistor supplied in the LLH1 sensor s connector produces a free air Vout of 4 00 Volts 2 85 1 337_ 19 66 20 73 8 56 19 39 2 90 11 405 20 66 21 78 8 99 20 38 Oz DIY WB and 5301 Display P7 Wiring and Connector Diagrams NIK Sensor 6300 Displa Sensor Canrnactar WB unit to Sensor Cable Oz DN we UNIT Long Cable ee Short Cable Bee Vo Sense E FED 1 Wout ERY silp Common mm BLACK 2 I Battery 124 RS232 Ip Pump Current CG wHITE 3 E Goud Ov Ground z alF BLUE 4 Cal GAEER amp Heater YELLOW Hester m DRANGE TF Eattery 12 m AED Ground OY mum ELACE The three connection points to the WB unit are represented above as CON1 the circular 8 pin connector on the left CON2 the DB9 on the right and CON3 the two wires coming directly from the WB unit The 5301 display is represented as the box showing 14 7 above The display is connected to the WB unit with a long 2 metre cable and a short cable from the display carries the RS232 data
4. Oz DIY WB and 5301 Display P1 Oz DIY wideband and TE 5301 display User s manual rev 0 0 Tech Edge Copyright 2002 Tech Edge Pty Ltd Oz DIY WB and 5301 Display P2 Introduction amp History The Oz DIY WB unit and the supporting 5301 display are available as both a kit and as prebuilt units from Tech Edge Pty Ltd The original DIY WB design originated from quite a few individuals whose aim it was to accurately measure AFR with the ultimate goal of getting a better tuned vehicle An SAE paper indicated that there was an NTK sensor that Honda used in their lean burn Civics in the early to mid 1990s This sensor was found to be available at fairly low cost compared to the cost of the same sensor when purchased with the very expensive AFR meters that were available at the time The DIY WB goal was to produce a simple interface that used the Honda NTK Sensor and which was fairly easy to build simple design but nonetheless accurate The Oz DIY WB unit is a realisation of that design and Tech Edge is proud to support the DIY concept through the Oz DIY WB as a kit and fully built unit The 5301 Display originated from a Silicon Chip magazine design for a narrow band oxygen sensor interface that was readily modified for use with the DIY WB Tech Edge has refined the original design and first offered it as the Modified Jaycar 5300 kit but demand was such that we eventually redesigned the project to use a new PCB and we c
5. alled it the TE 5301 display Oz DIY Wideband Unit description The Oz DIY wideband unit called the DIY WB or simply the WB unit comes ina tough grey impact resistant ABS plastic case with different connectors at each end One end top of fig 1 has a circular 8 pin plug for connection to an NTK L1H1 oxygen sensor via a cable The other end has a 9 pin D style connector and a power cable to connect to the vehicle s battery and charging system The D connector called a DB9 carries the output voltage Vout from the unit as well as power and ground for connection to the 5301 display or other display logging device The WB unit s power cable is wired to the target vehicle s electrical system ground and battery The power side of the cable is identified sensor Connector as the wire without any tracer and normally with a small section of red heatshrink plastic covering for positive identification The ground wire includes a tracer to distinguish it from the power wire It is very important that power and ground to the WB unit is not reversed The unit has some protection circuitry to prevent damage during normal operation but these protection devices will be damaged on power reversal and the WB unit will need some fairly low cost electronic components replaced The WB unit has just a single red LED Light Emitting Diode to indicate its operation The LED is lit when the WB unit is powered and the sensor is up to temperature an
6. arR Y eBAND O followed by the software version number say wW ah Bie 11 c and will then continuously display the AFR with a refresh rate of 2 5 times per second The display will show 14 7 or perhaps 14 6 anytime the WB unit detects the sensor is not up to operating temperature ie the WB unit s LED is OFF At other times the display will show some value between 10 1 and 24 9 If the WB unit senses a very rich mixture with AFR lower than 10 0 the display will show 10 S where the S is represented on the rightmost display as a 5 or S with a missing lower right segment If the WB unit senses a very lean mixture it will display 25 2 where 2 is represented on the rightmost display as a 3 with a missing lower right segment The RS232 optioned version of the 5301 has a short cable with a DB9 connector that may be connected to a PC or Palm device with a serial adaptor for data logging See the specifications section for information about the RS232 data that is sent out 5 times per second Fig 2 TE 5301 Display WB Unit Operational Requirements amp Connection The Oz DIY WB unit requires a minimum of 13 2 Volts measured at the battery end of the power cable Vehicle lead acid batteries rated at 12 Volts will normally have too low a terminal voltage to operate the unit unless the motor is actually running and charging to the nominal 13 8 Volt value for a
7. ble to provide Fig 3 NTK LLH1 Wideband Sensor another bung for the wideband sensor We recommend you place the NTK sensor a little downstream of the existing sensor and certainly before the catalytic converter The sensor should not be mounted with its wires pointing downward as this can allow water that may condense on the inside of the sensor s body during warmup to drip onto and crack the ceramic heater element inside the sensor s body Always mount the sensor 15 degrees or more to the horizontal in the 10 to the 2 o clock position with wires at the top The sensor wires are made from Teflon with a stainless steel core but ensure the connector and the cable it connects to which is made from PVC covered copper wire with a nylon sheath is kept right away from any vehicle heat above 80 C Some tuning shops use an adaptor that holds the oxygen sensor and this adaptor is then secured to the end of the vehicle s tailpipe This position is not recommended for vehicles with a catalytic converter as the converter will change the readings you are measuring that s the cat s main function in life For carby vehicles or non operational cats on EFI vehicles this position may also be a problem as the exhaust gasses can be quite cool after travelling the length of the car and the sensors heater may have to work too hard to maintain an operational temperature Serious tuning will require a hotter position closer to the manifold Vehicles
8. correctly adjusted charging system The DIY WB unit should not normally be connected to a cigarette lighter outlet because these connections are often fairly high resistance and experience voltage drop sufficient to prevent proper operation The best place is a pre existing high current relay operated by the ignition switch A fuse is a cheap and appropriate way to protect the WB unit and or your vehicle from damage Should a fault occur in either A 3 Amp or at most a 5 Amp in line fuse should be directly connected to the power cable the wire without the tracer and with the short section of red plastic heatshrink The Ground wire the wire with the tracer should be connected to an earth point close to the battery preferably using a solder or crimp lug that is bolted to an existing earthing chassis point This earthing point should carry a wire going directly to the battery negative terminal note all descriptions of power amp ground connection assume a negative earth system The WB unit draws a maximum of 1 5 Amps during sensor warm up and as low as 1 0 Amps after both the exhaust system and sensor have warmed up The WB unit s red LED will not be lit until the WB unit detects that the sensor is up to temperature This LED will also go out if the battery voltage falls below about 13 2 Volts during idle If the sensor cable is removed at either the sensor or the WB unit end the WB unit s LED will come on at a battery voltage as low as 11 5
9. d the battery alternator is sufficient to keep the lea sensor hot see operational requirements a below The LED will normally come on in 15 to DBO Output Connector 40 seconds after the vehicle has been started and is warming up at either a fast idle or on the road On some vehicles and with some sensor placements the LED may go out while the vehicle idles this normally indicates the alternator voltage has dropped below the WB unit s operational point because of accessories drawing power an old battery ineffective alternator or charging system or improper Fig 1 Oz DIY WB unit connection of the WB unit to the vehicle Power Cable Oz DIY WB and 5301 Display P3 5301 Display description The 5301 display uses a 3 digit superbright 7 segment LED display used to show AFR or Lambda and a 7 element vertical LED bar display to indicate rich or lean At the top left of the display face can be found a light sensing element called an LDR or Light Dependant Resistor wm This is a safety measure so the display s brightness automatically dims in low light The 5301 display connects to the WB unit using its longer and thicker grey 2 metre cable which supplies it with both power and the wideband signal The display normally indicates the AFR detected by the WB unit although it can be modified to read in Lambda units On powerup the 5301 display will show the s si 7 segment representations of the letters tE c
10. nominally 2 50 Volts and this point is shown as the bold horizontal line that crosses the bold vertical line at a lambda of 1 000 The table at right shows the Vout Lambda Petrol LPG Ethanol Diesel _ approximate AFR fora Auber different conidial 1 45 0 696 10 23 10 79 4 45 10 09 fuels petrol is also knownas 1 50 0 706 10 38 10 94 4 52 10 24 gas in North America or just 1 55 0 716 10 53 11 10 4 58 10 39 unleaded LPG is Liquid 1 60 0 727 10 69 11 27 4 65 10 54 Petroleum Gas Nevfirelcompositions are 1 70 0 750 11 03 11 63 4 80 10 88 seasonal and regional the 1 75 0 762 11 20 11 81 4 88 11 05 AFRs shown here should be 1 80 0 774 11 38 12 00 4 95 11 23 _ considered only as approx imate The 5301 display has an internal look up table and 195 0 814 41 96 12 61 5 21 11 80 _ displays the Petrol column for any given Vout input This 2 05 0 842 12 38 13 05 5 39 12 21 table may be used to convert 2 10 0 857 12 60 13 29 5 49 12 43 the 5301 s displayed petrol 2 15 0 873 12 83 13 53 5 59 12 66 value into an AFR for say LPG Alternatively if you have 2 25 0 905 13 31 14 03 5 79 13 13 logged Vout somehow this table can be used to convert 2 35 0 941 13 84 14 59 6 03 13 65 to the AFR for your particular 2 40 0 960 14 11 14 88 6 14 13 92 fuel 2 45 0 980 14 40 15 18 6 27 14 20 The stoic Vout is nominally 2 5
11. ossible from the engine itself Fig gt WB Unit to LIH1 The same colour coding scheme is use on the WB cable as is sensor Cable used on the NTK sensor itself The following table shows the pinouts of the sensor and the pins used on the circular 8 pin connector CON1 Figure 6 shows the pinouts of CON1 as seen by a person looking at the end of the WB unit Vs Vnb sense Red Vs Ip common Ip Pump current White Rcal po Fig 6 CON1 looking Heater a Orange at the WB unit Oz DIY WB and 5301 Display P6 Vout Specifications Lambda and AFR First some definitions The stoichiometric point is where all the available oxygen has combined with all the available fuel leaving no free residual oxygen AFR is the ratio of the quantity of air versus the quantity of fuel used at any instant Lambda is a ratio of 3 10 ratios and is equal to the 3 00 current AFR divided by the 2 30 stoichiometric AFR and is 2 00 1 0 exactly at the 2 0 stoichiometric point for any a given fuel wh The Vout signal pin 7 of 3 35 WB unit s DB9 connector is 2 30 converted to lambda using 2 10 Vout vs Lambda the graph at right The 2 00 lambda measure is 1 30 independent of the 1 50 hydrocarbon fuel being used ni The stoichiometric point is 4 s50 shown on the graph as the 1 40 bold vertical line atlambda 130 Lalana OF E2000 0 600 0 700 0 800 0 900 1 000 1100 1 200 1 300 1 400 1 500 The DIY WB stoichiometric output voltage is
12. sensor by measuring the WB unit s free air Vout This is the Vout obtained when the sensor has been sitting in free air for a period of a minute or so and has stabilised The ideal free air Vout is 4 00 Volts but this may vary from unit to unit and sensor to sensor It is possible to replace the Fig 4 LLH1 Sensor s factory supplied calibration resistor in order to improve the free air calibration We believe the standard WB unit will be accurate Connector Sumitomo enough for most users without having to do this WB Unit to Sensor Cable The standard cable lengths that may be suppled with the Oz DIY WB unit are 2 6 metres about 8 5 feet and 4 0 metres about 13 feet The cable lengths are approximate and will typically be slightly longer The cable has a circular connector at one end that allows it to be readily passed through the firewall of most vehicles An 18 mm hole just less than inch is required and should include a grommet or other device to prevent chafing against any sharp edges of the hole The complete cable is made up from a heavy duty figure 8 cable used to supply heater power to the sensor and a 4 core Shielded light gauge cable for the sensor signals Both individual cables are enclosed in a tough braided black nylon Sheath The cable must be protected from sources of radiant heat such as exhaust manifolds and should be routed to the WB unit using the shortest path that keeps the cable as far as p
Download Pdf Manuals
Related Search