G
AMATRONIC
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LECTRONIC
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NDUSTRIES
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Centric 3x480 Vac, Installation Guide, rel. 2.2
14
4.3.3
Site Preparation – Electrical
Perform the following procedures before connecting any external cables to
Centric
.
1.
Read Chapter
8 “Circuit breaker selectivity” in this installation guide. That chapter includes
considerations regarding the size of the external circuit breakers on the rectifier input and bypass
input lines.
2.
Verify that circuit breakers on the electrical board that supplies
Centric
are compliant with local and
national codes and Gamatronic system specifications. A fast fuse (semiconductor fuse) should be
used on the rectifier ac input line – for example, the Ferraz Shawmut A70QS,
3.
Verify that the input and output power cable connections, GND, and neutral lines comply with local
and national codes and are appropriate for the circuit breakers protecting them.
4.
Measure the ac input voltage. Phase-to-phase voltage (measured between L1-L2, L2-L3, and L3-L1)
should be 480 Vac ±10 %. Phase-to-neutral voltage (measured at L1, L2, and L3) should be 277
Vac, ±10 %.
5.
Verify that voltage between neutral and ground is between 0 and +2 Vac.
6.
Check the dc voltage at the switch of the battery cable. Measure the voltage between the “plus” side
and battery Neutral, and between the “minus” side and battery Neutral. Verify that the readings you
get are at least +240 V and -240 V.
7.
FAST FUSES (SEMICONDUCTOR FUSES) must be used between the battery and the Centric.
For example, the Ferraz Shawmut A70QS fuse.
