Simple Low Voltage Disconnect with Two Outputs

Pictured below is a low voltage disconnect circuit with two outputs.

low voltage disconnect (LVD) with two outputs to share the loadWe make a basic low voltage disconnect (LVD) designed specifically for use with low voltage LED lighting which incorporates a low-dropout 12V regulator. This device ensures that:

  • the battery does not get damaged by running too low on charge. If the measured voltage falls below 11.9V the output loads are switched off and not switched on again until the voltage is measured to be 12.5V or above.
  • the LED lighting is not damaged by excessive voltage (>13V) – particularly important with solar powered lighting systems where battery voltage can get up to 15V.

The pictured LVD/regulator is different in that it has dual outputs. The LM2940CT-12 voltage regulator is limited to around 1 Amp of output load, so our standard unit is not suitable in cases where the total LED lighting load exceeds around 8-10 Watts. Where the total load is more than around 2 Amps, we use an LT1084CP-12 regulator on the output side, but these are very expensive. Therefore where the LED lighting load is around 10-18 Watts, and can be split into a pair of separate lighting circuits, we simply make a double output regulator and split the load.

If you need something along these lines, email neil@reuk.co.uk with details of your requirements.


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