Basler Electric DGC-2020HD - Manual (Page 256)

246 9469300990 Rev B
•
NS (Not Sent) - String displayed for a J1939 parameter when the J1939 parameter has not been sent
to the DGC-2020HD by the engine ECU.
•
NA (Not Applicable) - String displayed for a J1939 parameter when the engine ECU sends a special
code for the parameter indicating that the parameter is not implemented or not applicable in the ECU.
•
UF (Unknown Failure) - String displayed when the J1939 parameter data received by the ECU is not
within the valid J1939 data range for the parameter but is not one of the special codes above.
Table 68 lists the J1939 data transmitted from the DGC-2020HD.
Table 68. J1939 Data Transmitted from the DGC-2020HD
ECU Parameter Update Rate SPN
∗
Address Claim Request† Once on power-up and any time a Global
Request for Address Claim (GRAC) PGN is
received
n/a
Auxiliary Analog Information 1.5 s n/a
Battle Override Switch 100 ms 1237
Clear Currently Active Diagnostic Trouble
Request† Whenever a request to reset Currently Active
Diagnostic Trouble Code Request is made
n/a
Clear Previously Active Diagnostic Trouble
Codes Request† Whenever a request to reset Previously Active
Diagnostic Trouble Code Request is made
n/a
Electronic Engine Controller #4 (Rated
Speed and Power) Request 1.5 s
n/a
Engine Hours/Revolutions Request 1.5 s n/a
Fuel Consumption Request 1.5 s n/a
Generator Frequency Selection
(0000-50 Hz, 0001-60 Hz) 100 ms
4080
Generator Governing Speed Command
(00-rated, 01-idle) 100 ms
4079
Governor Droop 100 ms 5568
Governor Gain Adjust 100 ms 5567
Liquid Fuel Information 1.5 s n/a
Previously Active Diagnostic Trouble
Codes Request 1.5 s
n/a
Speed Request 10 ms 518
Trip Fuel Reset 100 ms 988
∗ SPN: Suspect Parameter Number
† Requests from the DGC-2020HD to the ECU for various parameters are made by issuing the request.
ECU Limitations
For some ECUs, an external source cannot stop the engine without removing power from the ECU.
Turning off power to the ECU is the only way to remove fuel from the engine and shut it down. Different
ECU manufacturers have their own rpm setpoints for reapplying fuel to an engine. If the ECU is powered
up and the engine is still spinning above 60 rpm, then the ECU will automatically turn the fuel on. Detroit
Diesel J1939 ECUs, for example, have a setpoint of 60 rpm.
Not being able to stop the engine without removing ECU power causes two problems. The first problem is
that the only way to stop the engine is to turn the ECU off and wait for the engine speed to decrease
below 60 rpm before powering the ECU back on. Otherwise, the engine will take off running. The second
problem is that while the ECU is off, you can no longer meter and update coolant level, coolant
temperature alarm/pre-alarm, and crank control.
Communication DGC-2020HD