0100037-J0 Rev C
12
4.1.2 Rectifier Rear Panel
Refer to drawings at the end of this manual for shelf power and communications connections (compatible with 2.4kW recti-
fiers):
• 0300057-08
• 0300040-08
Refer to drawings at the end of this manual for the 3.0kW shelf ID version.
• 0300216-08
• 0300228-08
4.1.3 True Module Fail Alarm
The power modules have a “true” fail alarm that provides a true indication of the power module’s ability to source
current. When the module’s output current drops below 2.5% of the rated output, a low output current condition is
detected and the Module Fail detection circuit is activated. This circuit momentarily ramps up the output voltage to
determine if the module will source current. If no increase in current is detected, the
Module Fail
alarm is activated.
The module will test once every 60 seconds for the condition until a current is detected. The output voltage ramping
ceases upon detection of current. A minimum 2.5% load is required to avoid the
Ramp Test Fail
alarm. This load can
be provided with the parallel system battery. Activation of this alarm could indicate a failed module or a failed load.
To avoid nuisance alarms for Cordex rectifier systems without batteries, and/or with a very light load (below 2.5% of
the rated output), the ramp test should be disabled. Disable the Ramp Test via the CXC menu:
System > DC Sys-
tem > Inventory > Rectifiers > Configuration
.
4.1.4 Heat Dissipation
Each rectifier module is equipped with a front-mounted, variable-speed fan. The fan speed is determined based on
ambient temperature, rectifier temperature, and the load. Air flow is front-to-rear with the exhaust air exiting through
internal vents at the rear of the unit. The fan may spin in required situations.
4.1.5 Over Temperature Protection
Blockage or obstruction to the air flow can result in the internal temperature to rise and reduce the output power or
even shut down the rectifier. The rectifier will resume normal operation when the temperature reduces to a safe level.
Over temperature shut down can also occur when a fan failure has occurred.
4.1.6 Wide AC Range
The rectifier delivers up to 3000W of power between 187 Vac and 310 Vac input voltage. The rectifier can deliver up
to 1920W between 85Vac and 187Vac.
During start up the rectifier begins to provide power for input voltage >95 Vac and shuts down if the input voltage
drops below 85 Vac. The THD and power factor will be out of specs for input >277 Vac.
4.1.7 AC Inrush/Transient Suppression
To prevent a surge on the AC input line, the inrush current of a rectifier module is limited to the full load steady state
line current. Modules are also protected from input lightning and transient surges in accordance with IEEE/ANSI
C62.41 Category B3 standards.
4.1.8 Soft Start
A soft start feature is used to eliminate an instantaneous demand on the AC power source. A soft start, sometimes re-
ferred to as a “current walk-in”, works by gradually (up to five seconds) ramping up the DC output current limit from zero to
the actual or defined customer setting. The rectifier output voltage is ramped from the minimum voltage to the float voltage.
This feature along with Start Delay prevents any instantaneous surge demand on the utility.
4.1.9 Start Delay
The rectifier modules are equipped with a delay timer to stagger-start a series of modules. When multiple modules
and multiple shelves, part of a larger system are used in conjunction with a controller, a start delay prevents all recti-
fiers from starting at the same time and causing an inrush on the utility. The default start delay is set to 1 second
and can be adjusted up to 250 seconds on the CXC HP controller. The built-in timer delays the switching on of the
module by the start delay interval (up to 250 seconds), which is set in the controller.
