Installation Manual

Electrical & Electronic Application And Installation Manual
Production Release Version 1.0
Page 251 12/16/2014
20.2.1.3 TSC1 Continuous Fault Handling: [Disabled] (Default)
This mode is also known as Transient fault detection, it is suitable for
applications where there is more than one throttle input into the ECM, for
instance, in a wheeled excavator where the analogue throttle is used to
control road speed, but TSC1 is used to control the machine hydraulics. The
TSC1 message will override any other speed demand such as PWM throttle
pedal. TSC1 override is switched on and off using the Override Control Mode
SPN.
20.2.1.4 End of Transmission – Fault Detection
The ECM needs to differentiate between the end of a transmission by another
controller and an intermittent failure. The ECM expects, therefore, that when a
controller no longer wishes to demand engine speed then it will terminate with
at least one message with the Control Override Mode SPN set to 00. If the
engine sees that TSC1 messages have stopped, for 90ms or more, and TSC1
has not been terminated correctly then the ECM will recognize this as a fault,
a J1939 Diagnostic code will be raised and the ECM will not accept any TSC1
speed requests for the remainder of the key cycle.
20.2.1.5 TSC1 Continuous Fault Handling: [Enabled]
This mode is also known as Continuous fault detection, it is suitable for
applications where either TSC1 is the only throttle used or where TSC1 is
continuously used to limit the top engine speed. The TSC1 speed control /
speed limit cannot be switched off using the Override Control Mode SPN. For
instance, in a wheeled excavator the analogue throttle is connected to the
machine ECM that sends the TSC1 message to control road speed, and to
control the machine hydraulics. When TSC1 Continuous Fault Handling is
active, other throttles will be permanently over-ridden, and will only become
available if a TSC1 fault is detected.
20.2.1.6 Rating and Droop Control
In addition to Torque Speed Control, the complimentary message ‘OHECS’
allows droop and rating selection over J1939 with a similar effect to the hard-
wired ‘Mode Selection’ feature. The OHECS PGN is described later in this
section.