pgcroc
Hi
Can I use the Alpha Meter DCD-AVA.1 to check the stall current of a locomotive?
If I connect it between a Hornby Elite and a length of track and stall the loco would this give me an accurate stall current reading?
Many thanks
Peter
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m.bryan
I would venture to suggest that stall current isn't checked on DCC.
If it exceeds the decoder rating, then you may end up releasing the magic smoke.

The sensible option is to check stall current on DC with a blanking plug and a DC controller.
The Alpha meter can be used as it will automatically detect DC
Mick
DCCConcepts Tech/Customer support
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pgcroc
Thanks Mick
My fault, I should not have said an Elite. I always intended to use a DC controller to check the stall. 
Think my brains are scrambled!
Good that I can use the Alpha Meter.
Cheers
Peter
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AHJAY
And...

Be careful about stall current.

Stall current is not the real indicator I use. If you actually stall a loco by holding the motor under load almost ANY decoder out there will instantly heat up and burn out in perhaps one second (or less) and there is also genuine risk to the life of the motor, because heating is very rapid and heat = death to eleconics and motors.

What we really need to know is how things will cope with the maximum possible running current. The test for this is the SLIP current - when a loco is prevented from moving but the wheels are allowed to rotate, slipping on the rail. That is the highest reasonable current that can be expected.

Alternately, disconnect one motor brush and measure the resistance across the motor brushes. You can then use ohms law to calculate the maximum motor current draw. Alpha meter will give you an accurate DCC rail voltage reading to let you calculate, but you will need a multimeter for the motor resistance measurement.

Kind regards, Ahjay
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