Mitsubishi Electric MDS-D-SPJ3, Specification Manual

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Appendix 4 - 19
MDS-D-SVJ3/SPJ3 Series Specifications Manual
Appendix 4-6 EMC countermeasure parts
< Example of surge protector installation >
An example of installing the surge protector in the machine control panel is shown below.
A short-circuit fault will occur in the surge protector if a surge exceeding the tolerance is applied. Thus, install
a circuit protector in the stage before the surge protector. Note that almost no current flows to the surge
protector during normal use, so a circuit protector installed as the circuit protection for another device can be
used for the surge protector.
Installing the surge absorber
1. The wires from the surge protector should be connected without extensions.
2. If the surge protector cannot be installed just with the enclosed wires, keep the wiring length of A
and B to 2m or less. If the wires are long, the surge protector's performance may drop and inhibit
protection of the devices in the panel.
3. Surge protector to be selected varies depending on input power voltage.
B
A
MC
Circuit
protector
NC unit
Control panel
(relay panel,
etc.)
Other device
(panel power
supply, etc.)
Other device
(panel power
supply, etc.)
Panel earth
leakage
breaker
Input
power
Circuit
protector
AC reactor
Transformer
Grounding
Grounding plate
Factory power
Contactor
Circuit
protector
drive unit
(1) Surge protector
(Protection across phases)
(2) Surge protector
(Protection across each phase's grounding)
CAUTION