G
G
DEIF network
GENSET
controller
GENSET
controller
GENSET
controller
OR
OR
Event that forces controllers to SEMI mode
If one or more controller in the section with
connected
equipment is under Switchboard control, then all the controllers in the section
that are in AUTO mode are forced to SEMI mode. The EMERGENCY genset controller equipment is
connected
if the generator
breaker and the tie breaker are closed.
The controllers return to the return mode after switchboard when the cause is removed (
Configure > Parameters > Local power
management > Return modes > After SWBD control
).
More information
See
Power management
,
Power management protections
for the
Forced to SEMI mode
alarm.
2.3.6 Controller unpowered
A controller is unpowered if it loses power, for example, because its power supply is disconnected. When the controller is
unpowered, none of its protections and functions are active.
An unpowered controller does not communicate with the rest of the system, and is invisible to the rest of the system.
The following alarms are activated when a controller detects that one of the system's controllers is unpowered:
•
Missing controller ID #
•
Missing any controller
Effect of the unpowered controller hardware
DEIF network links through the unpowered controller are broken. If a redundant DEIF network link is not available, the controllers on
either side of the unpowered controller cannot communicate with each other. If a redundant DEIF network link is available, then the
controllers on either side of the unpowered controller communicate through the redundant link.
All relays return to their de-energised hardware condition. For example, on IOM3.1 there is a changeover switch on terminals 1 to 3.
If the controller loses power, then there will be an open circuit between terminals 1 and 2 (the normally open terminals of the
changeover switch), and a closed circuit between terminals 2 and 3.
The analogue output terminals on GAM3.1 (terminals 12 and 13, and terminals 16 and 17) and GAM3.2 (terminals 3 and 4, and
terminals 5 and 6) will have a resistance of over 10 MΩ.
INFO
Even though a controller relay may be configured as normally energised, it is also de-energised if the controller loses
power.
CAUTION
Class societies require an independent backup power supply for the controller, to avoid having an unpowered controller.
DESIGNER'S HANDBOOK 4189340911K UK
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