Using A Stepped Voltage - AEMC 6550 User Manual

Use the ▲▼ buttons to select a preset test voltage ramp:
■
Ramp function 1: 50 to 500V
■
Ramp function 2: 500 to 5000V
■
Ramp function 3: 1000 to 10,000V
The voltages at the beginning and end of the ramp can be programmed with the CONFIG button (see § 2.4.3).
The duration of the test is the sum of the three durations specified: the duration of the initial level, the duration
of the ramp, and the duration of the final level.

4.4.5 Using a Stepped Voltage

The preset stepped voltage tests have ten levels. The duration of each of the voltage levels is identical. At the
end of each level, the capacitive current should be zero and only the measurement current remains.
Unlike the ramp test, the step test stresses the insulation and can cause a breakdown. A sudden increase of
the current (or a sudden decrease of the insulation resistance) means that a breakdown point is near. It is then
possible to discontinue the measurement manually by pressing the START/STOP button or automatically using
E-BRK or Break at I-Limit type of test (see § 2.4.3).
A drop of 25% or more between the insulation resistance of the first level and that of the second level is a sign
of deterioration of the insulation.
Set the rotary switch to the V-STEP position. The following screen appears:
SET-UP
V RAMP
V VAR
V FIXED
Use the ▲▼ arrow buttons to choose the preset step type of test:
■
Step function 1: 50 to 500V
■
Step function 2: 500 to 5000V
■
Step function 3: 1000 to 10,000V
The voltage and the duration of each step can be programmed using the CONFIG button (see § 2.4.3).
Megohmmeter Models 6550/6555
Shop for AEMC products online at:
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Step
Voltage
OFF
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STEP FUNCTION
Min. 50 V
Test Run Time 00:01:40
Input voltage
Frequency
Input current
Date 2011.05.24
.ca
BURN
1
Max. 500 V
1 V AC
50.0 Hz
24.6 nA
Time 15:31
1.877.766.5412
31