ELTEX Terrabox TCB030, Руководство по эксплуатации

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BA-en-4003-2005_TUE30
5. Maintenance
Before carrying out maintenance or service work in the explosion hazard
area, make sure that there is no potentially explosive atmosphere in the
working zone.
Warning!
Maintenance and repair work must be carried out only by specially
qualified personnel.
Cables and clamps must not be damaged. Damaged cables and clamps
must be replaced with new parts.
5.1 Ground control units
Check the units at regular intervals for proper function, in doing so check
the operating points and the earthing resistance. The intervals for the
control are to be specified according to the application and therefore,
depending on the operating conditions, by the operator.
No other maintenance work is required.
Checking the operating points
Determine the operating points (see chapter 8 Technical specifications) by
using a decimal resistor.
Checking the resistance to earth
Active clamps:
To measure the earthing resistance between clamp jaw and ground (PAL)
the supply voltage to the ground control unit must be disconnected.
When using TCB030/TCO030 standard version with ground clamp 70AG
or 70AK the resistance value is (depending on the measuring voltage of
the measuring device):
between ground and clamp jaw 1: 15 - 60 kOhm
between ground and clamp jaw 2: 14 kOhm, ±20 %
When using TCB030/TCO030 BIG-BAG version with ground clamp 70BG
or 70HK the resistance value is:
between ground and connected clamp jaws: 14 kOhm, ±20 %
Ex!