9 soft start, 10 start delay, 11 current limit/short circuit protection – Alpha Technologies Cordex 48-1.2kW User Manual
Page 15: 12 power limiting, 13 high voltage shutdown (hvsd), 14 battery eliminator operation, 2 distribution module, Distribution module

030-834-J0 Rev A
Page
9 of 34
2.1.9
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 rectifier output voltage is ramped up from the
minimum voltage to the float voltage.
2.1.10
Start Delay
The rectifier 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.
2.1.11
Current Limit/Short Circuit Protection
The current limit function determines the maximum output current limit of the rectifier 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.
2.1.12
Power Limiting
Each rectifier 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.
2.1.13
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.
2.1.14
Battery Eliminator Operation
Rectifier 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.
2.2
Distribution Module
030-834-20 (Cordex CXRF-HP 48-1.2kW center mounting 2RU shelf for systems up to 4800W)
The shelf incorporates a distribution module for DC breaker/fuse output as well as battery connections. The
module includes support for up to four AM plug-in breakers and ten GMT fuse positions. Two battery-
landing positions, a 125A battery shunt, and a site ground are also provided. It may also incorporate an
LVBD.
This module contains a unique sliding connection point system to allow for the several dual-hole lug
terminations in a compact space. See Wiring and Connections chapter of this manual for more details.