Hi Clive.
Below are responses to the questions I asked of the manufacturer:
They are most helpful people.
I would check carefully the regulator is correctly earthed and the battery is good condition.
I recommend fitting a transient suppressor.
Transient voltage suppression (TVS) diodes are inexpensive compared to the cost of the electronics.
Mark
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> 1. What is the maximum allowed input voltage of the electronic module?
18V
> 2. Does the electronic module contain over voltage and/or transient
> protection?
No, this would lower the minimum operating voltage.
And take care that the battery is fully operating
and properly wired with good contacts. An old dying battery and bad
contact produce voltage spikes that might destroy the electronics.
The battery acts as a buffer to smoothen out the voltage. Without
battery you'll get a very dirty voltage not suitable to drive modern
electronics.
Regards,
Marco Patzer