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GMC-I Messtechnik GmbH
Limit Values per DIN VDE 0701-0702, Part 1: 2008
1)
If the limit value is fallen short of, an equivalent leakage current measurement must be performed and
passed.
Note
: “OL” at the display means measured value > 20 M
Ω
.
Evaluation of Measured Values
Device measuring error must be taken into
consideration in order to make absolutely sure that
the limit values for insulation resistance have not
been fallen short of. The following table allows for
calculation of the required minimum value for
insulation resistance which must be displayed at the
device in consideration of maximum measuring error
(under nominal conditions of use), in order to assure
that the required limit values are not fallen short of
(DIN VDE 0413, part 1). Intermediate values can be
interpolated.
Attention
!
!
Insulation resistance must be measured with a test probe connected to the
appropriate socket (4) in accordance with figure 5.2 at all exposed, conductive parts
for protection class II and III devices, as well as for battery powered devices.
This test is omitted for protection class III and battery powered devices which fulfill the
following conditions:
Nominal power
≤
20 VA
Nominal voltage
≤
42 V
Batteries must be disconnected during testing of battery powered devices.
Note!
In the event of long-term short-circuiting in the 20 MOhm range, measuring current is
reduced after approximately 10 minutes. This is indicated by a triangle which appears
at the top left-hand portion of the display panel. A nominal current of 1 mA, as
specified by DIN VDE 0413 and DIN VDE 0701-0702, is no longer assured when the
triangle appears. After the short-circuit has been eliminated and a brief cool-down
period has elapsed, the triangle disappears and measurements once again comply
with VDE conditions.
Device Type
Limit Values
Min. Display Value
Protection class I devices
1M
Ω
1.15 M
Ω
Protection class I devices with heating elements
0.3 M
Ω
1)
0.38 M
Ω
Protection class II devices
2.0 M
Ω
2.25 M
Ω
Protection class III and battery powered devices
1000
Ω
/V and 250 k
Ω
Limit Value, M
Ω
Min. Display Value
0.25
0.33
0.3
0.38
0.5
0.60
1.0
1.15
2.0
2.25
7.0
7.75
10.0
11.05