If the cooling-down temperature is set to 0 deg., the cooling-down sequence will be entirely
controlled by the timer.
4.8.6 Breaker sequences
The breaker sequences will be activated depending on the selected mode:
Mode
Genset mode
Breaker control
Auto
All
Controlled by the unit
Manual
All
Push-button, M-Logic, Modbus, Digital input
Block
All
Controlled by the unit
Before closing the breakers, it must be checked that the voltage and frequency are OK.
Setpoints related to MB control
7080 MB control
Mode shift:
When enabled, the controller will perform the AMF sequence in case of a mains failure
in load takeover or TEST mode
MB close delay:
The time from GB OFF to MB ON
Load time:
After opening of the breaker, the MB ON sequence will not be initiated before this de-
lay has expired. Please refer to the description of "Breaker spring load time".
If no MB is represented, the relays and inputs normally used for MB control become configura-
ble.
The GB can only be closed if the mains breaker is open. The MB can only be closed if the gen-
erator breaker is open.
- AMF MB opening
(7060 U mains failure)
It is possible to select the functionality of the mains breaker closing function. This is necessary if the unit op-
erates in Automatic Mains Failure (AMF).
The possibilities are:
Selection
Description
Start engine and open
mains breaker
When a mains failure occurs, the mains breaker opens, and the engine starts at
the same time.
Start engine
When a mains failure occurs, the engine starts. When the generator is running
and the frequency and voltage are OK, the MB opens and the GB closes.
4.8.7 AMF timers
The time charts describe the functionality at a mains failure and at mains return. The timers used by the AMF
function are indicated in the table below:
CGC 400 DRH 4189340786 UK
Functional descriptions
DEIF A/S
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