20 Appendix 2
ASCO Series 230 C2ADTL Transfer Switch User Manual
Appendix 1 Surge Protection Device
1. In order to run the Automatic Transfer Switch reliably, SPD
’s are needed before connecting the Automatic Transfer
Switch to Source I and Source II. It is recommended that the SPD wire connections use V shape wiring method
shown in Appended Figure 1. When limited by practical conditions, and if it is difficult to adopt V shape wiring, one
can also use routine direct-parallel-connection method shown in Appended Figure 2. The connection wire should be
as short as possible (less than 0.5m) when using direct-parallel-connection method to achieve better protective
performance.
2. The connection wires should be multi-core copper wire with a cross-sectional area greater than 10mm
2
(AWG6).
3. Appropriate MCB or Fuse should be serial-connected to the front-end of the SPD for AC power supply. The MCB
should
have the ”C” tripping characteristic.
4. The power supply should be cut off when installing SPD
’s. Live installation is prohibited. All the wires must be
connected properly, and using correct wires.
5. While the SPD does not need special maintenance, it is recommended that one periodically checks whether the
indicators of the SPD are functioning normally and to make sure the modules are not loose.
6. If either of the following situations appear, the SPD has failed and needs to be replaced.
1) The SPD indicator turns red.
2) The SPD remote signal contact becomes an open-circuit.
7. The Wiring method show in Appended Figure 3 is forbidden. If SPD is wired similar to Appended Figure 3, the
wiring needs to be modified to Appended Figure 1 or Appended Figure 2.
Source
I
Source
II
MCB or Fuse
Class C Surge
Protection Device
Surge Protection
Device Wiring from
Main Circuit to
Grand lenth
≤0.5m
Connection Wiring
Lenth
≥1m
Series230
Transfer
Switch
Load
Grouding Cable
Lenth
≤
0.2
m
Controller
Cable line
≤
2m
L1
L2
L3
N
L1
L2
L3
N
Connection Wiring
Lenth
≥1m
MCB or Fuse
Surge Protection
Device Wiring from
Main Circuit to
Grand lenth
≤0.5m
Class C Surge
Protection Device
L1
L2
L3
N
L1
L2
L3
N
Source
I
MCB or Fuse
Source
II
MCB or Fuse
Cable Line
≤
2m
Connection Wiring
Lenth
≥1m
Connection Wiring
Lenth
≥1m
Series230
Transfer
Switch
Controller
Grouding Cable
Lenth
≤
0.2
m
Load
Surge Protection
Device Wiring from
Main Circuit to
Grand lenth
≤0.5m
Class C Surge
Protection Device
Surge Protection
Device Wiring from
Main Circuit to
Grand lenth
≤0.5m
Class C Surge
Protection Device
Appended Figure 1:
V Shape Wiring Method
Appended Figure 2: D
irect-Parallel-Connection Method
L1
L2
L3
N
L1
L2
L3
N
Source
I
MCB or Fuse
Source
II
MCB or Fuse
Cable Line
≤
2m
Connection Wiring
Lenth
≥1m
Connection Wiring
Lenth
≥1m
Series230
Transfer
Switch
Controller
Grouding Cable
Lenth
≤
0.2
m
Load
Surge Protection
Device Wiring from
Main Circuit to
Grand lenth
≤0.5m
Class C Surge
Protection Device
Surge Protection
Device Wiring from
Main Circuit to
Grand lenth
≤0.5m
Class C Surge
Protection Device
Appended Figure 3:
Wrong Connection Method
