PTDB90690001.qxd:PTDB9069-02.qxd
General Information
3.1 Appropriate Usage
The instrument may only be used under those con-
ditions and for those purposes for which it was con-
ceived. For this reason, in particular the safety ref-
erences , the technical data including environmental
conditions and the usage in dry environments must
be followed.
When modifying or changing the instrument,
the operational safety is no longer ensured.
The instrument may only be opened by an au-
thorised service technician, e.g. for fuse re-
placement.
Service and maintenance may only be carried
out by an authorised service technician.
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15:36 Uhr
4.0 General Information regarding
Insulation Measurement
For electrical installations the insulation measure-
ment has to be carried out prior to final commis-
sioning. This measurement is of basic importance
as the insulation measurement (protection against
dangerous body currents) is considered to be the
only measurement for fire protection. If, due to an
insulation error, a limited fault current flows be-
tween two conductors, this leads to a heating up or
even to a fire. Only the insulation measurement pro-
cedure can detect such a fault.
According to DIN VDE 0100 Part 610 the insulation
resistance measurement is carried out:
• from all external conductors (e.g. B. L1, L2, L3)
towards ground or towards the grounded protec-
tive earth (PE)
• between protective earth (PE) and neutral (N)
Additionally, it is advised to perform the following
measurements:
• between all active conductors (e.g. L1, L2, L3, N).
This measurement has to be carried out separately
for every individual current circuit. This measure-
ment is performed using a DC voltage of 500 V.
Table 1 Test Voltages
Description of the System
Nominal voltage
Test of other signal
systems
Derivation ability of
floor covering in
compliance with
DIN 51953
SELV / PELV
system
Systems
up to
(except SELV /PELV)
Systems above
500 V up to 1000 V
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Test Voltage
Limit Value
50 V
-
100 V
1 MΩ
250 V
0.25 MΩ
500 V
500 V
0.5 MΩ
1000 V
1MΩ