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Voltage from Variable PSU for track - What Level?

I was given a R915 Power Controller and thought I'd test it first using a multimeter as the PSU is old.

The supply is suppose to be 12V DC and I'd expected it to be variable depending on dial position.

However (with no load) the output remains constant at 17 Volts.

Being new to this I don't have a second PSU to reference the R915 against.

It drops to zero when at the minimum dial setting but just above that the voltage is constant all the way round the dial to the maximum setting.

Is this constant voltage output normal regardless of setting?

Though I'd ask you folks before I blew up a loco :)

Cheers

Pete

Reply to
Pete
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Some power controllers use a resistor to control output; if yours is one of these, the lack of a load on the output will let the output voltage be maximum and the dial will have no effect. To test without smoking an engine, get an automobile tail light lamp and put it on the output; you should see the voltage vary with dial position.

Reply to
kt0t

Thanks for the suggestion.

I need to sort around and find a suitable load. I'll post results when tested.

Cheers

Pete

Reply to
Pete

Thanks Kt0t... tested now and works fine.

Cheers for help.

Pete

Reply to
Pete

You're welcome Pete; glad it worked.

Reply to
kt0t

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