Ampcontrol VAA, User Manual

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VOICECOM USER MANUAL ISSUE 4
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Auto-shutoff
If the battery voltage falls below 5.9V, it will shut down its output to prevent causing permanent damage to the SLA
battery cells. This will occur if there is insufficient charging current available from the communication line.
Sleep Mode
The battery pack can be put to ‘sleep’ to conserve battery charge and protect the battery cells from damage. Putting
the battery pack to sleep forces its output to shut down. The battery pack should be put to sleep if the communication
line power supply is not available i.e. when the VAA is not connected to the communication line.
To put the VAA to sleep:
1. Disconnect the VAA from the VoiceCom communication line
2. Momentarily connect a piece of wire between terminals 1 and 6 of the battery pack header, as shown in
Figure 29. A piece of wire can either be inserted in the holes on top of the header or into the socket holes.
3. The VAA display will go blank when the battery has shut down.
4. Remove the wire from the header.
Waking the VAA
To ‘wake’ up a VAA that has shut down, connect the VAA to a VoiceCom communication line with a power supply
voltage greater than 11Vdc.

A VAA that has been put to sleep and has enough charge will wake up straight away.

A VAA that has shut down due to low charge will have to be connected to a communication and recoup
enough charge. The VAA will not wake up until the battery voltage has risen above 6.0V. This may take
several hours depending on how depleted the battery charge is.
If the VAA does not wake up, the battery back may have become damaged. Refer to the Troubleshooting chapter for
more information on fault finding VAAs.
Power Supplies
Only connect the VAA to an I.S. power supply with output parameters that match the VAA input parameters, as
outlined in Certificate of Conformity Aus Ex 03.3881X.
Figure 29 - Putting the VAA to Sleep
wire
1
6