Alpha Technologies 030-706-J0 Installation & Operation Manual Download

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030-706-J0 Rev B

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2.6

Wide AC Range

A minor alarm is generated when the AC input voltage drops below 180Vac. Output power is reduced linearly
below 150Vac to 40% of the rated output power. At a lower voltage the module will shut down and will not restart
until the AC is greater than or equal to 150Vac.

For voltages above 276Vac, power factor and total harmonic distortion may be derated. For voltages between
277Vac and 320Vac, the rectifier may not be operational but shall not suffer any damage.

2.7

AC Inrush/Transient Suppression

The modules’ inrush current is limited to less than one times the nominal peak line current to prevent surge on the
AC line. Modules are also protected from input lightning and transient surges in accordance with IEEE/ANSI
C62.41 Category B3.

2.8

Soft Start

To eliminate an instantaneous demand on the AC source, a soft start feature is employed. Soft Start, sometimes
referred to as “current walk-in”, works by gradually (up to five seconds) ramping the current limit up from zero to
the actual or defined customer setting. The output voltage is ramped up from the minimum voltage to the float
voltage.

2.9

Start Delay

The modules are equipped with a delay timer in order to stagger start a series of modules to prevent excessive
loading of generators upon start up. The built-in timer delays the turn on of the module depending on the value
selected (up to 120 seconds) via the CXC. A minimum one-second delay is preset to allow charging of the input
capacitors.

2.10 Current Limit/Short Circuit Protection

The current limit function determines the maximum output current limit of the module, regardless of output voltage
or power. Maximum output current is limited to a constant value down to short circuit condition. Current limiting
can be used to mate the rectifier output current ampacity to the needs of the load and parallel battery to minimize
excessive battery recharge current.

The rectifier will sustain a short circuit at the output terminals indefinitely. The maximum short circuit current shall
not exceed 105% of the rated full load current.

2.11 Power Limiting

Each module is designed to limit power output to the module specification. This enables more current to be
supplied at lower output voltages, and allows matching of output to the demand of constant power loads, normally
seen with telecom equipment.

This feature may also be used for a faster recharge of flooded batteries paralleled with the load.

NOTE: Current limiting overrides the power-limiting feature.

2.12 High Voltage Shutdown (HVSD)

This feature provides protection to the load from over voltage conditions originating from the rectifiers. It operates
by shutting down the offending rectifier module when a high output voltage condition occurs. Indication is through
the red Alarm (Module Fail) LED. Modules will restart automatically; however, if more than three over voltage
conditions occur in one minute, the module will latch off and remain shut down until it is reset via the CXC.

2.13 Battery Eliminator Operation

Modules maintain all specifications (except where indicated) with or without a battery attached in parallel to the
output; however, if a battery or another module supplying DC voltage in parallel is not present, there will be no
monitoring or control activity if there is an AC power failure or input fuse failure.