Specifications

98AEtypSMSspec_RevC.doc

SP-0012 Rev. C 09/05/09

input current total harmonic distortion (THD) into the utility AC input source at nominal

voltage and rated load. The reflected input current shall typically not exceed 9% THD at

50 % load.

C. Automatic Input Power Walk-in

The rectifier logic and control circuit power walk in function enables delayed and timed

ramping of input current. Subsequent to energizing the rectifier input, initiation of the

power walk in function and current ramping shall be delayed by a maximum of 3600

seconds (every 1 second adjustable – default at 10 second). Upon initiation of the power

walk-in function, the ramping of current shall be timed to gradually increase the load

within 10 seconds. This function is included as standard in the rectifier control circuitry.

D. Input Overcurrent Protection

Converter input contactor, input fuses, and the input current limit control shall provide

rectifier protection against excessive input overload conditions.

E. Step Load Change Operation (0-100%)

In the occurrence of a 100% step load change, the UPS Module inverter shall draw

power only from the rectifier to provide the required load demand. The charger/booster

shall not be utilized and the system batteries will not be cycled at any time during a step

load change.

2.2.1.2 Charger/Booster

A. General

The charger/booster utilizes solid state Pulse Width Modulation (PWM) controlled

Insulated Gate Bipolar Transistors (IGBT). The charger switching frequency is 10kHz,

and the booster switching frequency 2kHz.

B. Battery Charge Current Limit

The charger logic and control circuit DC battery current limiting function enables

controlled battery charging. The battery charge current limit will control the recharge

current by reducing the rectifier/charger output when the set limit is reached. The

following battery current limit shall be provided as a minimum:

1. Battery charge current limit: 10% of battery Ah rate.

2. Maximum charge current: 13% ampere of UPS rated kVA.

(e.g. 13ADC maximum of 100kVA UPS)

C. Equalize Charge Timer

UPS Module logic and control shall provide an electronic equalize charge timer function

(0 to 50 hour selectable - default twenty-four (24) hour). Once activated the timer circuit

shall provide a high rate equalizing charge voltage to the system battery for the selected

time. The function can be manually activated and de-activated via the UPS Module LCD.

The level of equalizing voltage shall be equal to that stated by the battery manufacturer

(typically .04 to .08 VDC/cell higher than the specified float level). Upon completion of

the timer count, the converter output voltage shall return to the specified float voltage

(typically 2.25 to 2.27 VDC/cell). An Auto Equalize charge operation is also provided