Motec PLM User manual

MoTeC PLM User’s Manual
Contents
Introduction ...................................................................... 3
Meter Operation................................................................ 4
PLM Connections ..........................................................................................................4
Connectors..............................................................................4
Analog Output..........................................................................4
Digital inputs............................................................................5
Communications ......................................................................6
PLM Display....................................................................................................................6
Sensor Placement.........................................................................................................7
Sensor Warm-up...........................................................................................................9
Sensor Lifetime..............................................................................................................9
Lambda.........................................................................................................................10
Engine Tuning..............................................................................................................10
Operating Tips..............................................................................................................11
PLM Setup Software.........................................................12
Computer requirements.............................................................................................12
Connecting to a PLM...................................................................................................12
Installing PLM Setup...................................................................................................12
Configurations..............................................................................................................12
Managing Configurations.........................................................13
Changing Configurations .........................................................14
Sensor Calibration ...........................................................19
Introduction...................................................................................................................19
Calibration Methods....................................................................................................19
Use Measured Calibration Value..............................................19
Enter Calibration Value...........................................................19
Calculate from O2 Concentration (Free Air)...............................20
Enter Calibration Table............................................................21
PLM Communications.......................................................22
CAN Messages............................................................................................................22
Configuring Basic CAN with an ADL.........................................23
Configuring basic CAN with an M800........................................23
CAN Collect Functionality...........................................................................................24
Configuring the CAN collect master unit (PLM 1).......................24
Configuring the CAN Collect slave units (PLM 2 to PLM
16)........................................................................................25

MoTeC PLM User’s Manual
CAN Unit Number Display.........................................................................................26
RS232 Messages........................................................................................................27
Specifications...................................................................28
Meter....................................................................................28
Appendices ......................................................................31
AppendixA –Lambda to Air Fuel Ratio Table........................................................31
Appendix B –PLM Display Codes............................................................................32
Appendix C–PLM CAN Diagnostic Codes ............................................................33
Appendix D–PLM Connector Details......................................................................34
Appendix E –Sensor Wiring Details........................................................................36
Bosch LSU 4 Sensor..............................................................36
NTK –UEGO Sensor..............................................................38
Appendix F –PLM to ECU Wiring Details................................................................40
Analog Output........................................................................40
CAN......................................................................................40
Appendix G –PLM to ADL Wiring Details................................................................41
Appendix H–General CAN Bus Wiring...................................................................42
Appendix I –PC Comms Wiring...............................................................................43
Appendix J –Analog Output Wiring..........................................................................44
Appendix K –Digital Input Wiring..............................................................................46
Typical wiring for switches.......................................................46
Typical wiring for RPM measurement .......................................46
Appendix L–Glossary................................................................................................47
AppendixM –CAN Messages Format.....................................................................48
Appendix N–RS232 Message Format...................................................................53
Appendix O –Recommended CAN Collect Configuration..................................54
Appendix P –Dimensions .........................................................................................57
Copyright –Motec Pty Ltd –2001-2005
The information in this document is subject to change without notice.
While every effort is taken to ensure correctness, no responsibility will be taken for the consequences of any
inaccuracies or omissions in this manual.
23 June, 2005

MoTeC PLM Setup Software 3
Introduction
The MoTeC Professional Lambda Meter measures Lambda (or Air Fuel Ratio)
over a wide range of mixtures with fast response time.
The display may be set to Show Lambda, Air Fuel Ratio (for Petrol, Alcohol,
Gas, Diesel or ‘blend’ fuel), equivalence ratio or percentage oxygen.
The PLM provides a differential Analog Output Voltage proportional to Lambda
that may be connected to an Analog Meter or other measurement instrument
such as an ECU, Data Logger or dynamometer.
The PLM also supports RS232 and CAN data links to devices such as the
Motec Dash Logger or M800 ECU for transmission of sensor and diagnostic
data.
This manual covers the configuration and operation of the meter.

4Meter Operation
Meter Operation
PLM Connections
Connectors
The PLM has a male and a female D-9 pin connector.
See Appendix D–PLM Connector Details for a description of the PLM pinout.
Male Connector
The loom supplied with the PLM is fitted to the male PLM connector, for
connection to the sensor and to a power supply. The Power supply must
provide enough current (up to 5 Amps at start up) for both the meter and the
sensor heater element. The vehicle battery is typically the most convenient
source of power.
It is not recommended that the power and sensor loom be extended by using a
standard serial cable. These are unable to supply the current required by the
sensor heater. If an extension is made, the wire must be at least 20 gauge.
Female Connector
The female PLM connector has pins for serial connection to a PC, CAN data
bus, 2 digital inputs and the analog voltage output.
The pinout is assigned to allow direct connection to a PC with a standard
(straight through) 9 pin serial cable. Note that the PC must have a serial
communications port (normally marked COM1). A custom cable is required to
use the other features on this connector.
Analog Output
The analog output provides a voltage proportional to Lambda. The scaling of the
analog output can be changed by using the PLM Setup software to configure
the device (see Setup | Analog Output in the PLM Setup Software section).

MoTeC Meter Operation 5
The analog output is provided as a differential voltage using two connector pins
(Analog Out+ and Analog Out-). For correct operation Analog Out-must be
connected to the ground reference on the monitoring system.
The analog output can be configured as a wide band sensor input into a MoTeC
ECU for tuning, as described below. See Appendix F–PLM to ECU Wiring
Details for wiring details.
M4/M48 ECU
PLM Configuration Output Function = ‘LA V1’ table
La = 0.000, Aout = 0.000V
La = 5.000, Aout = 5.000V
ECU Configuration Lambda Sensor Calibration =1 (‘Narrow Band or
MoTeC AF Meter’)
M8/M800
PLM Configuration Output Function = ‘LA V1’ table
La = 0.500, Aout = 0.000V
La = 1.750, Aout = 5.000V
ECU Configuration Lambda Sensor Calibration =39 (‘MoTeC Meter’ or
‘MoTeC AFM1 Meter’)
Digital inputs
Digital Input 1 can be enabled as a switch input or RPM input. If the input is
enabled, the PLM can be configured to operate based on the switch state
(active high or active low) or on a non-zero RPM reading. The RPM reading is
also transmitted in the CAN and RS232 data streams.
Digital Input 2 can be enabled as a switch input, and the PLM can be configured
to operate based on the switch state (active high or active low). This input can
also be configured to change the display units on the PLM display. For more
information, see Setup | Digital Inputs in the PLM Setup Software section.
The digital inputs have a 4.7kohm pull-up resistor, and a switching threshold of
around 2.5volts.

6Meter Operation
Communications
RS232 Interface
The RS232 interface is used for configuring the PLM from a PC, and for
transmitting data to third party equipment.
For configuration from a PC, the PLM can be directly connected using a
standard (straight through) 9 pin serial cable.
See Appendix I–PC Comms Wiring for details on wiring to a PC.
CAN Interface
The CAN interface is used for transmitting data to MoTeC devices such as the
ADL (Advanced Dash Logger) or M800 ECU, or to third party equipment that
supports CAN.
The CAN communications can be configured to allow one PLM unit to collect
CAN data from up to 15 other PLM units, and then retransmit the data on a
single CAN address and on the RS232 interface.
For detailed information on communications interfaces, see the PLM
Communications section.
PLM Display
Start-upDisplay
On powerup, the PLM displays the current firmware version (eg. 1.1.0) for one
second, followed by a unit number based on the current CAN communications
configuration.
This unit number, displayed for one second, is useful for troubleshooting
networks of multiple PLM units. See the PLM Communications section for more
detail on displayed unit numbers.
Status Display
Whenever the sensor is not in control or is warming up, a series of displayed
codes describes the current status. A description of these codes is given in
Appendix B –PLM Display Codes.

MoTeC Meter Operation 7
If the PLM loses control of the sensor at any point, then the sensor warm-up
process is repeated and these codes are displayed again.
Sensor Readings
The displayed format of sensor readings can be configured to select the display
units, decimal places, update rates and filtering. For more information, see
Setup | Display in the PLM Setup Software section.
If the reading is too large to be displayed using the configured settings, the
display will only show ‘--‘.
Backlighting
The backlight intensity is configurable from 0% to 100%.
Sensor Placement
The sensor should be fitted to the exhaust system with the sensor tip protruding
into the exhaust gas flow. The sensor placement should be on an angle of
between 10 and 90 degrees to the vertical, with the tip of the sensor pointing
down. This is to ensure that no condensed water builds up between the sensor
case and the sensor ceramic. It should not be placed vertically due to excess
heat soak in this position.
It is recommended that where possible the sensor be placed at least 1m from
the exhaust ports to avoid excessive heat and at least 1m from the open end of
the exhaust system to avoid incorrect readings due to outside oxygen. This is
however not mandatory, and where necessary for shorter exhaust systems the
sensor should be placed closer to the engine.
The placement of the sensor should be away from the flame front coming out of
the cylinder head and away from areas where one cylinder may have more
affect than another.

8Meter Operation
Incorrect sensor placement
Correct sensor placement

MoTeC Meter Operation 9
Exhaust slip joints should be avoided near sensor placement as some designs
allow air to enter. Slip joints can be reversed to make them better for use near
sensors.
Sensor Warm-up
The internal heater in the LSU or NTK sensor is powerful enough to allow
accurate measurement when gas temperature is at room temperature. The
Bosch LSU will take ~20seconds to heat up, while the NTK ~30 seconds before
reading.
The maximum continuous operating temperature of the sensors is 850 degrees,
and sensors should not be used for a prolonged period at temperatures higher
than this. The sensor can be heated to 930 degrees for a short period (not
exceeding 10 minutes), but the accuracy may be reduced.
Sensor Lifetime
The sensor life time is dependant on the type of fuel being used and the volume
of gas flow over the sensor. The sensor can also be contaminated by exhaust
manifold sealants, so Exhaust Gas Sensor friendly sealants should be used.
Leaded fuel will reduce the sensor lifetime substantially due to lead
contamination of the sensor element. Typically, for high performance engines
the sensor should last at least 500 Hrs in unleaded fuel and 50 Hrs in leaded
fuel. Longer lifetimes can be expected for less demanding applications.
Exhaust slip joint design to avoid incorrect lambda readings
Exhaust flow
Introduced a
ir
No air i
ntroduced

10 Meter Operation
At the end of its life the sensor becomes slow to respond and does not read
rich properly. The NTK and LSU are designed to be accurate for 50,000km of
operation in a road car, so the above figures are a conservative estimate.
Sensor lifetime will be reduced by contaminants such as lead, silicon, oil, etc.
Thermal cycling will also age the sensor more rapidly, along with exposure to
exhaust fumes without any heating control active (ie: not connected to the
PLM). Regular performance of the Free Air Calibration will maintain the
accuracy of the sensor over its lifetime.
Sensor Temperature
It is important to ensure that the sensor is not overheated due to incorrect
placement in the exhaust as this significantly reduces the sensor life. The
sensor impedance (Zp) ismeasured by the PLM, and this is a reasonable
indication of sensor temperature. Zp should be approximately 80 Ohms in
normal operation. If Zp is less than 60 the sensor is being overheated by the
exhaust and the sensor life will be reduced.
Lambda
Lambda gives a measure of Air Fuel Ratio that is independent of the type of fuel
being used.
Lambda 1.0 corresponds to the stoichiometric ratio i.e. when there is no excess
fuel and no excess air.
Lambda > 1.0 => Excess Air (Lean)
Lambda < 1.0 => Excess Fuel (Rich)
Lambda may be directly converted to Air Fuel Ratio for a specific fuel using a
multiplication factor. The PLM will display Air Fuel Ratio by loading the
appropriate configuration into one of the output tables. For more information,
see Setup | Display in the PLM Setup Software section.
A table to convert Lambda to Air Fuel Ratio for various fuels is given in Appendix
A –Lambda to Air Fuel Ratio Table.
Engine Tuning
The desired Air Fuel Ratio (or Lambda) is dependant on the tuning objective i.e.
Power, Economy or Emissions. Normally at full load the engine is tuned for