Powerdynamo, PD AC systems, fuse blows when lights are off

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AC Regulator: Fuse blows when lights are turned off

Sounds a little weird, but often in systems with a Powerdynamo AC regulator  the fuse blows when lights are switched off.

  • this small AC regulator is of a type that burns surplus voltage (not the case in our DC regulators) l
  • So, with lights off, the regulator tries to burn all offered voltage. The result is some high current (depending on revs) of around 10 Ampere. With lights on this  sinks to about 6A.

As it happens that motorcycles equipped with our AC system are driven (even if briefly) without lights the fuse might blow.

We are therefore renouncing on the fuse in our AC wiring instructions. That is the fuse in our AC systems is omitted  as the AC system does not have a battery anyway. 

Given the high current (and the heat generated with this) systems with this regulator imperatively need to drive always with lights on. The energy produced by the alternator has to be consumed as otherwise the regulator trying to consume it will heat up considerably, leading not only to risk of destruction of the regulator, but also the risk of fire. (Alternatively you may drive conmpletely without regulator should you not need lights. Than just keep the 2 black wires from the generator insulated (!) idle.
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