American Power Conversion DC Series External Battery Installation, Battery Back-up function

4.4 External Battery Installation

4.4.1Battery Back-up function

Battery backup may be achieved by connecting 48V strings of batteries onto the external battery terminals of the distribution module at the rear of the system. This battery string will be connected to the system bus voltage via an internal LVD contact. If for any reason the rectifier outputs are not present, either by component failure or by the loss of AC power then the battery string can supply the load for a limited time.

4.4.2LVD Function

An internal LVD contact is fitted for battery string protection. Its function is to connect or disconnect the battery string from the system bus. The LVD can be set to “ON”, “AUTO”, or “OFF”. In the On position the batteries are connected to the system bus. In “Off” the connection is broken. In “Auto” the batteries are connected to the system bus under normal system running conditions. If the system bus voltage falls the battery string will supply the load. If the battery voltage then falls below 42Vdc the LVD contact opens and disconnects the batteries to protect them. When system bus voltage is re-established the battery string will be trickle charged until the battery voltage is >50Vdc and then the batteries will be reconnected to the system.

4.4.3Installation procedure

!!! CAUTION !!!

Only connect external battery strings of 48V to the MX06 40A Shelf.

External batteries MUST have circuit breakers fitted at source.

Observe the polarity of the external battery connector.

See section 4.3.4 for connection photo.

Note : It is possible to connect external battery strings of different capacities but the backup duration will be affected.

•Ensure the battery breaker/s for the external batteries are in the ‘OFF’ position before connecting external batteries.

•Set the front panel “battery connection” switch to “OFF”.

•Choose cables rated at 50A and colour coded to meet local installation regulations.

•Cables should be crimped with M5 ring crimps for connection to system battery terminals.

•Connect battery string to system ensuring correct polarity of connection.

•Conduct a final check before turning on the external battery breaker.

User Manual 990-9178A	Page 39 of 44	18th FEB 02
DC MX06 40A Shelf