4-26
4-3 Wiring Conforming to EMC Directives
4
System Design
Surge Absorbers
Use surge absorbers to absorb lightning surge voltage or abnormal voltage from power supply
input lines.
When selecting surge absorbers, take into account the varistor voltage, the allowable surge
current, and the energy.
For 200-VAC systems, use surge absorbers with a varistor voltage of 620 V.
The surge absorbers shown in the following table are recommended.
Note 1.
Refer to the manufacturers’ documentation for operating details.
Note 2.
The surge immunity is for a standard impulse current of 8/20
μ
s. If pulses are wide, either
decrease the current or change to a larger-capacity surge absorber.
Dimensions
Equalizing Circuits
Maker
Model
Max.
limit
voltage
Surge
immunity
Type
Remarks
Okaya
Electric
Industries
Co., Ltd.
R·A·V-781BWZ-4
700 V
±
20%
2500 A
Block
Single-phase
100/200 VAC
R·A·V-781BXZ-4
700 V
±
20%
2500 A
Three-phase
200 VAC
200
2
8
41
4.5
4.2 dia.
4.2 dia.
11
5.5
2
8
.5
5.5
11
2
8
.5
200
2
8
41
4.5
Single-phase B
W
Z Series
Three-phase BXZ Series
Single-phase B
W
Z Series
Three-phase BXZ Series
