4.3. System Management
System Output Capacity
The
System Voltage Control
The PSCU 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 PSCU removal or failure, the shelf rectifier controller card will control the voltage at a programmed default level. In the event of shelf rectifier controller card failure, the individual rectifiers will default to the analog voltage level preset with the front panel “float’ adjustment pots.
System Current
The PSCU monitors individual rectifier currents and displays total system current as a sum of rectifier currents. Load current can be found by adding battery current to system current. Battery Current is positive when the battery is discharging.
Sys Current + Batt current = Load Current
For example, if the battery is charging the Batt Current reading could be
Sys Current + Batt current = Load Current 120A +
If the battery is discharging the Batt Current reading would be 40 A, Sys Current would reading would be 40 A. Load voltage would be:
Sys Current + Batt current = Load Current 40A + 40 A = 80 Amps.
System Status and Alarm Reporting
The PSCU will monitor system voltage using a high accuracy digital voltmeter attached to the system bus. The PSCU will monitor system temperature using a temperature IC mounted in the PSCU. The PSCU will monitor system current by summing the current reported by individual rectifiers. The PSCU will report a number of system alarms including system high/low voltage and high/low temperature. Refer to Section 4.6 for PSCU control functions.
MX28B400 +24 VDC User’s Manual | Page 21 |