50 ABB Power Distribution
6.2.9 Earthing and short-circuiting with the earthing
cable sets
(Figures 3/12, 3/13, 3/19, 6/12, 6/16 to 6/20)
1. Earthing in the cable compartment
For the earthing of the tee-off conductors, the
usual commercially available earthing bolts are
intended for use on the connecting bars and the
main earthing bar in the cable compartment.
Handling:
• Use earthing cables with insulating rods in
accordance with the manufacturer’s
instructions.
• Check for off-circuit condition.
• Attach a warning label with an earthing symbol
to the panel door.
2. Earthing at the contact pins
An earthing system with cable cross-sections of
70 mm
2
to 150 mm
2
is also available on request,
specifically for earthing at the fixed contact pins.
a) Handling for earthing at contact pins for rated
currents up to 1250 A:
• Isolate the area to be earthed and secure
against reconnection.
• Remove the withdrawable circuit-breaker
part from the relevant panel.
• Secure shutter 12.1 in front of the live
contact pins with padlock 130.
• Bolt on actuating bars 129.1 to the shutter
operating module 129 at the required
location:
– at the top to open the lower shutter,
– at the bottom to open the upper shutter.
• Move the shutter operating module 129
into the test/disconnected position and
completely into the service position with the
aid of hand crank 121.
• Check that the area to be earthed is off-
circuit, e.g. with a high-voltage tester at the
relevant contact pins 4.1 or at the cable
terminal.
• Connect the earthing cable to the fixed
earthing point.
• Fit the short-circuiting cables directly onto
the contact pins using insulating rod 133.3,
and fasten them in place by turning the
insulating rod.
• Attach warning label with the earthing
symbol to the panel door.
• Secure neighbouring live areas (e.g.
possibly the feeder cables) to prevent
inadvertent contact.
b) Handling for earthing at contact pins for rated
currents above 1250 A:
• Isolate the area to be earthed and secure
against reconnection.
• Remove the withdrawable circuit-breaker
part from the relevant panel.
• Secure shutter 12.1 in front of the live
contact pins with padlock 130.
• Bolt on actuating bars 142.1 to the testing
and earthing module 142 at the required
location:
– at the top to open the lower shutter,
– at the bottom to open the upper shutter.
• Fit withdrawable test and earthing part 142
with contact arms 142.2 and contact
systems 142.3 at the required positions.
Remove ball 142.4 and short-circuit bridge
142.8 if fitted.
• Move the testing and earthing module 142
into the test/disconnected position and
completely into the service position with
the aid of hand crank 121.
• Check that the area to be earthed is off-
circuit, e.g. with a high-voltage tester at the
relevant contact pins 142.7 or at the cable
terminal.
• Connect the earthing cable to the fixed
earthing point.
• Fit the short-circuiting cables to contact
pins 142.7 using insulating rod 133.3, and
fasten them in place by turning the
insulating rod.
• Attach warning label with the earthing
symbol to the panel door.
• Secure neighbouring live areas (e.g.
possibly the feeder cables) to prevent
inadvertent contact.
6.3 Test procedures
6.3.1 Testing the off-circuit conditon
(Figure 6/4)
The panels are fitted with a capacitive voltage
indication system including the corresponding
(hand-held) plug-in indicator for testing of the off-
circuit condition.
A distinction must be made between the low
resistance (LRM) system and the high resistance
(HR) system. For further details, see draft standard
VDE 0682 Part 415 or IEC 61243-5.
The two systems differ in several respects,
including different voltage levels which constitute
the display thresholds. The capacitive voltage
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