Larson Davis 831C-FFT, Reference Manual

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SoundAdvisor Model 831C Powering the 831C SLM 14
You may also see this error when the batteries become too hot or too cold. Optimal battery
temperature is 0° C–45° C.
2.2.2 Using External Power
The following available external power sources augment the 831C’s internal battery:
• USB port from a computer
• USB port from PSA029 power supply
• I/O connector from an ex10.8 to +25 Volt DC mains power source.
Accessing External Power by Using the USB Port
Step 1.
Connect the PSA029 power cable to an external power source on one end and to
the included USB Type B power cable (CBL138) on the other end.
Step 2.
Then insert the mini-USB (Type B) connector into the mini USB (Type B) port on
the bottom of the meter.
CAUTION
If you operate the 831C without batteries and power is interrupted, you may
loose your data.
With the PSA029 power supply connected and operating at rated conditions, the 831C
operates properly with or without batteries installed. Use the included cable (or another
cable with the same gauge wire) to prevent excessive power loss.
2.2.3 Understanding 831C Power Events and Indications
Understanding a Low Voltage Shutdown Event
The 831C preserves the service life of an external battery by preventing it from being
discharged excessively. When the battery voltage drops below the External Shutoff Voltage
(default value +10.8 volts) and remains above +10.2 volts for one minute, the instrument
stops, saves data, and turns off.
Understanding a Power On After Power Loss Event
When the 831C is powered from an external supply and the input voltage falls below the
indicated External Shutoff Voltage threshold, it powers off. When the 831C shuts down due
to a low battery, it automatically attempts to power up after a short reprieve. If there’s
adequate power, it remains on. However, if the battery is still discharged, it powers off. This
attempted “power on” cycle continues until the meter has sufficient power to remain on.
This feature is designed to allow the 831C to automatically restart when power is lost due
to low solar situation or after an extended power outage.
LEARN MORE
To learn more about reboot time after a power loss, see “Low Power At
Boot-Up” on page A-7.