Idle Running; Description - Deif CGC 400 Reference Book

CGC 400 DRH 4189340786 UK

7.10 Idle running

7.10.1 Idle running
The purpose of the idle run function is to change the start and stop sequences to allow the genset to operate
under low temperature conditions.
It is possible to use the idle run function with or without timers. Two timers are available. One timer is used in
the start sequence, and one timer is used in the stop sequence.
The main purpose of the function is to prevent the genset from stopping. The timers are available to make the
function flexible.
The speed governor must be prepared for the idle run function if this function is to be used.
The function is typically used in installations where the genset is exposed to low temperatures which could
generate starting problems or damage the genset.

7.10.2 Description

The function is enabled and configured in 6290 Idle running. It has to be noted that the governor itself must
handle the idle speed based on a digital signal from the unit (see the principle diagram below).
When the function is enabled, two digital inputs are used for control purposes. These inputs must be config-
ured through the Utility software:
No. Input
1 Low speed in-
put
2 Temperature
control input
If the idle run function is selected by means of the timer, the low speed input is overruled.
Turbo chargers not originally prepared for operating in the low speed area can be damaged if
the genset is running in "idle run" for too long.
DEIF A/S
This input is used to change between idle speed and nominal speed. This input
does not prevent the genset from stopping - it is only a selection between idle and
nominal speed.
When this input is activated, the genset will start. It will not be able to stop as long
as this input is activated. To use temperature control it is necessary to enable idle
speed in parameter 6295.
Description
Additional functions
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