Ac Mains Protection Unit; Sparkover - Phase Surge Protection Device (Spd) - Hitachi E-Compact Medium Power Series Operation Manual

6.5. AC Mains Protection Unit

The AC Protection Unit is responsible for the AC Power distribution and Equipment AC Power
protection.
Characteristics:
⇨ Surge Protection Device (SPD).
⇨ Circuit Breaker.
⇨ AC Line Input.
⇨ AC Mains Internal distribution.
⇨ AC Mains Available:
M208
B240
T208 / T240
T380

6.5.1. Sparkover - Phase Surge Protection Device (SPD).

It is a device that limits overvoltages in the mains by diverting the current line to ground, in order to limit
the amplitude of this overvoltage to a value that is not dangerous to the equipment. It is connected in
parallel between the line and the ground and has high impedance. Once the transient overvoltage appears
in the system, the impedance of the device decreases and directs the current to earth protecting the
equipment. When this occurs, the device signals a red flag, needing for its replacement:
RED:
Fault
Warning
1 Φ 190~240VAC
Neutral
GND
2 Φ 190~240VAC
GND
3 Φ 190~240VAC
GND
3 Φ 190~240VAC
Neutral
GND
Mains
Protection
Unit
EC Medium Power – Rear View
Sparkover Changing
E-Compact Medium Power
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