Page 69
Issue 07/2011
Operation
Power generation system operation
5.5.3
Warning / disconnect with faulty insulation
All of the power sockets fitted in the switch cabinet (except for the
emergency socket) are equipped with an insulation monitor. If the insulation
of a connected line or device is faulty, the insulation monitor will disconnect
all of the power sockets except for the emergency socket to protect persons
working on the power generation system.
y
The current insulation resistance is displayed on a display instrument
on the switch cabinet (
ð
Figure 11, page 64). The scale on the display
instrument is divided into separate colors according to the state of the
insulation (“OK” = green, “Critical” = yellow, or “Poor” = red).
Warning when insulation value < 34.5 kΩ (equivalent to 150 Ω/V)
y
When the insulation resistance lies between 23 kΩ and 34.5 kΩ, the
warning lamp will light up Insulation fault and a warning buzzer will
sound. In general, the power generation system can continue to be
operated with all of the connected devices, though the faulty devices
and/or cables should be located and disconnected as soon as possible to
remedy the fault.
y
To localize a faulty device or faulty cable, disconnect the devices / cables
individually one after the other; at the same time, look for a change in the
display insulation resistance on the switch cabinet.
Immediate disconnect when insulation value < 23 kΩ
(equivalent to 100 Ω/V)
y
When there is an insulation resistance less than 23 kΩ, all power sockets
except for the emergency power socket are disconnected immediately;
the warning lamp insulation fault lights up, and a warning buzzer sounds.
y
In this case, immediately locate faulty devices and/or cables to remedy
the fault, and disconnect them. The power sockets are not switched back
on again until after the warning message was acknowledged and the
insulation resistance is larger than 23 kΩ.
y
To locate the faulty device or cable, one option is to disconnect all of the
devices / cables, acknowledge the warning message and then connect
the devices / cables to the generator one by one, watching the insulation
resistance on the switch cabinet as you do so.
Summary of Contents for DWG (BL) 13/7-2 ZE
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