Mω: Insulation Resistance Measurement With 50V, 100V, 250V, 500V, 1000V Test Voltage; Measurement Procedure - MARTINDALE VR2250 User Instruction Manual

6.2. MΩ: INSULATION RESISTANCE MEASUREMENT WITH 50V, 100V, 250V,
500V, 1000V TEST VOLTAGE
These measurement comply with IEC 61557-2 and VDE 0413 part 1.
Before affecting the insulation test make sure that the circuit under test is
not energised and all the loads are disconnected.
Turn the switch to the MΩ position.
The key F1 permits to select one of the following measuring modes:
Mode "MAN" (Manual mode). Recommended test.
Mode "TMR" (Timer mode: test duration depends on the selected interval
from 10 to 999 seconds). This test can be performed when the test
requires a defined duration.

6.2.1. Measurement Procedure

1. Select the desired mode by means of the F1 key.
2. Connect the test leads to the instrument input terminals B1 and B4 respectively,
Example: insulation measurement between phase L1 and earth in a 3 PHASE electrical installation
using test leads.
3. If the cables supplied with the instrument are not long enough for the measurement
you can extend the black cable.
4. Connect the instrument terminals to the object which is to be submitted to the
insulation test after de-energizing the circuit under test and all the relative
loads (see previous picture).
5. By means of F2 select the test voltage suitable for the type of test to be carried
out (see Table1). The values to be selected are:
• 50V (test on telecommunication system)
• 100V
• 250V
• 500V
• 1000V
RED
BLACK
I1
B1 B2 B3
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CAUTION
M
B4
VR2250