Mitsubishi Electric FR-S520E Series Instruction Manual page 204

Precautions for maintenance and inspection
Item
Across STF,
Start signal
STR, RH, RM,
Select signal
RL-SD
Across A-C
Alarm signal
Across B-C
CAUTION
1. Use an FFT to measure the output voltage accurately. An FA tester or general
measuring instrument cannot measure accurately.
2. When the carrier frequency exceeds 5kHz, do not use this instrument since
using it may increase eddy-current losses produced in metal parts inside the
instrument, leading to burnout.
In this case, use the approximately effective value type instrument.
Measuring
Point
Moving-coil type
(Tester and such may
(Internal resistance:
50k
Moving-coil type
(such as tester)
Measuring
Instrument (Reference Measurement Value)
When open
be used) 20 to 30VDC
ON voltage: 1V or less
Ω
or larger)
Continuity check
Across
A-C:
Across
B-C:
194
Remarks
<Normal> <Abnormal>
Discontinuity Continuity
Continuity Discontinuity