APC VS 100 Power Supply User Manual


 
Magnum VS –48 Vdc User’s Manual Page 20
5 Technical Description
The Power System is designed to supply safe –54 Vdc primary power through the use of up to
10 rectifier modules. The controller will monitor all functions and provides battery management
including controlled battery recharge with temperature compensation and low voltage
disconnect. Integrated dc output distribution supports loads ranging from ¼ A all the way to 60
A. The controller can monitor up to 4 discrete external events with voltage free (“dry contact”)
user inputs.
5.1. Rectifier Management
AC Input Power
The basic component of the power system is the rectifier module, which rectifies utility ac into
nominal 48 Vdc. Each rectifier module requires 85 – 264 Vac, 47 – 63 Hz single phase power.
Available cord sets include a variety of blade and twist lock plugs. Dedicated wiring inside
conduit can also be used.
DC Output Power
The dc outputs of all the rectifiers in the system are connected to a common bus that is rated to
carry the current of the entire system. The rectifier modules will equally share the entire load,
independent of the controller. The rectifiers will continue to provide dc power (-54.5Vdc) if the
controller is removed or fails.
Rectifier alarms reporting
The rectifier has numerous sensors inside the unit that monitor fan fail, high temperature,
high/low voltage, etc. These rectifier sensors trigger outputs that are monitored by the
controller. In addition rectifier current is measured inside each rectifier. The controller can
trigger output relays in the event of a rectifier alarm. Refer to Section 5.5 for controller functions.
5.2. System Management
System Voltage Monitor and Control
The controller monitors and adjusts the system voltage. It uses a voltage trim input to the
rectifier to precisely control the dc output voltage. In the event of controller removal or failure,
individual rectifiers will default to the analog voltage level (-54.5 Vdc) preset at the factory.
System high and low voltage alarms are reported by the controller.