4-33
4-3 Wiring Conforming to EMC Directives
System Design
4
Surge Absorbers
Use surge absorbers to absorb lightning surge voltage and 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
Manufacturer
Model
Surge immunity
Type
Remarks
Okaya Electric
Industries Co., Ltd.
R·A·V-781BWZ-4
700 V
±
20%
2,500 A
Block
Single-phase
100/200 VAC
Okaya Electric
Industries Co., Ltd.
R·A·V-781BXZ-4
700 V
±
20%
2,500 A
Three-phase
200 VAC
1 2 3
28
4.5
28.5
11
5.5
41
200
4.2 dia.
Three-phase BXZ Series
2
1
28
4.5
28.5
11
5.5
41
200
4.2 dia.
Single-phase BWZ Series
Three-phase BXZ Series
Single-phase BWZ Series