Eaton APS12-300 Series, Инструкция по установке и эксплуатации

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Transient Protection
Copyright © 2007-2013 Eaton Corporation. All Rights Reserved.
IPN 997-00012-49G May 2013
89
Transient protective devices are fitted with alarm contacts and visual indicators.
Monitor the status of all externally installed transient protective devices. Either:

Regularly inspect the visual indicators

Connect the alarm contacts to the MOV Fail termination on the I/O board (preferred
option) or to the building management system. See the Connections diagram on page
11 for
location of MOV Fail termination (YH3) and connector pin-outs on page 84 .

The alarm signal lines of the external transient protective devices must be isolated from the ac
supply (by voltage-free relay contacts) before connecting these signal lines to the APS dc power
system.
Secondary Transient Protection
Secondary transient protection (downstream from the primary transient protection) must be
present at all sites to protect the dc power system from transients.
Some models of Access Power Solutions are factory-fitted with secondary transient protection
to protect the power system from a limited number of repeated 15kA transients (8/20µs wave
shape).
Factory-fitted secondary transient protection typically consist of:

Phase-to-neutral metal oxide varistors (MOVs) with a voltage rating of 440V, capable of
withstanding temporary over-voltages

A neutral-to-earth spark gap (gas discharge tube)

Surge decoupling coils
If secondary transient protection is not fitted inside the Access Power Solutions, then external
secondary transient protection must be installed in the ac switchboard that supplies the dc
power system.
Carefully consider the residual voltage seen by the dc power system (maximum 6kV) and the
decoupling between the transient protection system and the dc power system. Transients must
be limited to less than 2kA.
Tertiary Transient Protection
Eaton rectifiers are fitted with 6kV/3kA transient protection. This is designed to protect the
rectifiers from voltage spikes generated during operation of the upstream transient protection
system. Do not install rectifiers without adequate upstream surge protection.