Eaton EFX48 e-Fuse Series - Page 57

Installation
Copyright © 2019 Eaton Corporation. All Rights Reserved.
IPN March 2019
57

AC supply

Primary transient protection devices

High voltage protection unit with alarm output

Secondary transient protection devices (MOVs)

DC power system

EFX48 GPIO inputs

EFX48 e-Fuse unit

Rectifiers
Step 2 - Check the type of ac supply
Check the type of ac supply. Only the types of ac supply listed in the Specifications on
page 138 are suitable for the RM3-340/440.

Only use an ac supply referenced to ground, or with a protection system so that
the phase-ground voltage cannot exceed the rating of the rectifier.
Step 3 - Disconnect device and overcurrent protection
1 The socket outlet(s) shall be installed near to the RM3-340/440 and shall be
readily accessible.
2 Each socket shall be protected by an overcurrent protection device (a circuit
breaker suitable for Branch Circuits and rated 15A or less).
3 The external circuit breaker(s) must be two-pole type wired in each conductor, if:
• the ac supply is 2W (see Specifications on page 138), or
• the ac supply is 1W+N but the neutral is not clearly identified.
Step 4 - Check ac discrimination
Each rectifier has two internal fast-acting fuses. Under certain internal fault conditions
these fuses will blow.
If there is insufficient discrimination between these fuses and an upstream ac
supply-disconnect device supplying the RM3-340/440 then the ac supply to all
rectifiers will be disconnected if a rectifier fuse blows.
1 Check the time-current (tripping) curve(s) of all ac supply-disconnect device(s)
upstream of the RM3-340/440 with the following curve for the rectifier fuses.
 Refer to the manufacturer's data for tripping curves.
2 No action is required if the time-current curves of the upstream ac supply-
disconnect devices are entirely to the right of the curves for the rectifier fuses.
3 If the curve of an upstream ac supply-disconnect device crosses the curve for the
rectifier fuse there may not be adequate discrimination. Contact your Eaton dc
product supplier for advice (see Worldwide Support on page 161).

There is a maximum rating for the first upstream circuit breaker(s). See Step
3.