Ac Output Circuit Breaker; Cable Connection And Static Switch Module; On-Line Mode; Off-Line Mode - MGE UPS Systems 3.5 to 21 kVA N+1 Owner's Manual

3.5 to 21 kVA N+1 Inverter
Inverter rating
DC breaker rating

3.4.2.2 AC Output Circuit Breaker

It is not required, but highly recommended. A power "Distribution" panel is available from MGE UPS Systems at a
nominal cost. Order part number XXXXXXXXX, which will accommodate up to 24 single-pole circuit breakers,
"Square-D" QO type.

3.4.2.3 Cable Connection and Static Switch Module

All input and output connection terminals are mounted inside the built-in "Static Switch". It is very easy to identify
this module by looking at a front panel that has twin cooling fans. This front panel can be opened with a #2 "Phillips"
screw driver. When making connection, always double check to make sure that DC cable goes to DC bus bars,
identified as (+) and (-). The utility cables go to a terminal block, 120/240VAC connects to TB1-2, NEUTRAL to TB1-4.
AC output is from TB1-1 (120/240VAC), NEUTRAL to TB1-3. One of the best ways to verify continuity is to use a DMM.

3.4.2.4 ON-LINE Mode

ON-LINE mode is the mode in which the load is powered by the invert system, not the utility. It will get clean,
transient free electrical power from the inverter system, which is producing the AC power from a DC power source.

3.4.2.5 OFF-LINE Mode

OFF-LINE mode is the mode in which the load is powered from the Utility power line (external AC input power). In
the event of a power failure, a static transfer switch will connect the system output to the inverter and activate the
inverter so as to provide continuous power to the load with no interruptions of power to the load.

3.4.2.6 Troubleshooting Guide

After having thoroughly reexamined the installation and setup of the system, and still found it un-operational, user
can follow Table 3-2 to identify a problem, its cause, and recommendations for fixing it.
Table 3-2: Troubleshooting
Problem
Display panel not illuminated
No output voltage
System starts, then shuts
down almost immediately
Power module LED turn red
Module temp. indicator on

3.4.2.7 Inverter Configuration

3.4.2.8 Battery Booster

Battery booster is a push-pull type converter on which average current-mode control scheme was employed for
better dynamic response. The circuit utilizes a high frequency transformer for obtaining a pair of +213.5/-213.5Vdc
output and for galvanic isolation as well.
page 3 — 4
3.5 kVA 7 kVA
125A 250A
Possible Cause
No power to system
SW1 not ON
Overload, or shorted
output.
Module faulted
Module fan failure
Maintenance
10.5 kVA 14 kVA
375A 500A
Possible Solution
Check AC % DC power sources.
Turn SW1 ON
Remove some of the load and
restart the inverter.
Reset by recycling circuit breaker
Replace module or cooling fan
17.5 kVA 21 kVA
650A 750A