Issue

What is the proper way to place a Single-Phase Symmetra UPS into maintenance bypass?


Product Line

Symmetra Power Array
Symmetra RM
Symmetra LX


Environment

All serial ranges


Cause

Single phase Symmetra UPS systems feature a maintenance bypass mode that can be initiated physically by the user used to bypass the power modules and intelligence modules and provide utility power to the attached equipment in the event of an emergency or if both intelligence modules must be removed.  This document describes the proper way to enter the maintenance bypass state for a single phase Symmetra UPS system.


Resolution

The ideal method of transferring the load to maintenance bypass on a Single-Phase Symmetra UPS is to first command the UPS to bypass before engaging the maintenance bypass switch/breaker.

The following sequence should be used:

1. From the PowerView display, go to "Control" / "UPS into Bypass" and press "Return".

2. Answer "Yes".

3. Engage the Maintenance Bypass Switch. (Do Not Open the Input Breaker, the critical load will be dropped if the Input Breaker is opened).

4. Now the unit is in Maintenance Bypass. While in this state, tasks such as removing both intelligence modules or cycling the System Enable switch can be done.

Caution: There is still power present inside the Symmetra frame. Only the Power, Intelligence, and Battery Modules can be safely removed / replaced.  If work is to be performed inside the frame, it needs to be done by APC's Field Service Engineers when the UPS is fully powered down.

Publicado para: Schneider Electric Argentina