Output/Signals
Auxiliary output (Optional)
An auxiliary output is provided for customer equipment. This is common 0V with the main and battery outputs.
Thermistor
A thermistor lead is supplied which must be used to ensure correct operation of the battery charger.
The thermistor should be sited close to the batteries being charged.
A fault condition will occur if the thermistor is short or open circuit. (See troubleshooting).
Volt free contacts (factory defaults)
Two sets of VF contacts are provided which indicate fault conditions.
Charger status indicates loss of charger (mains failure or failure of PSU). It is also used to indicate a thermistor
fault.
Battery status is used to indicate a battery low or disconnected condition.
Battery Output
All Oracle units are battery backed, having a separate output to charge the batteries. In the event of a mains
failure an internal diode back feeds the battery current to the main output.
The battery output has a pre-set current limit.
Main output
Main output is derived from the power supply during normal operation, from the batteries during mains out. The
main output has a pre-set current limit.
Start-up conditions
The unit runs a self-diagnostic after application of power, in which the input/output conditions are examined in
order to give rise to relevant alarm indications. Allow circa 30 seconds for stabilisation after all connections are
made and power applied.
Batteries
The charger is designed for VRLA batteries; please consult the factory for suitability of other types. Please
ensure the battery/batteries installed are of the correct type. Use of non-specified batteries may result in false
battery low alarms (in units with battery test).
External fusing for the batteries must be provided. There is no battery fuse internal to the unit.
Safety note: Please consult manufacturers data before using batteries. Avoid short circuit. Observe polarity.
Battery test (optional)
Initiation of battery test can be implemented either through software, or by pressing the test button on the side of
the unit. The battery test will only initiate when the battery is in a sufficient state of charge to give a relevant
result.
See also “LED functions”
Under Voltage Lockout (UVLO)
Under Voltage Lock Out is a battery protection feature.
The unit constantly monitors battery voltage, and disconnects the battery at a predetermined (in software)
voltage. This prevents deep discharge when running from batteries.
Temperature compensation
The unit provides temperature compensated charging.
The unit is supplied as standard with thermistor lead for remote sensing applications. This should be situated as
near as practical to the battery/batteries.
LED / Volt free relay functions (factory defaults)
Note: all other combinations of the PSU present conditions above will produce a fault.
For Volt Free Relay connection details see unit label.
Serial Communications (Optional)
For units fitted with the serial comms option please see the applicable VXI application note for further
information.
