Re: (ET) Elec-trak Digest, Vol 19, Issue 88

[Erv Troyer <reo43 aol com>]

David,
 So many times I have heard someone say "Lower volts causes higher amps" 
which totally defies Ohms Law. UNLESS - your load is being controlled by 
something that tries to maintain speed (power) at any voltage.  
Compressors in an air conditioner are speed controlled by the Hertz of the 
power supply - they have to maintain a constant speed to keep the flow of 
refrigerant going at the same volume. In this case when the voltage drops 
the compressor will still maintain the same speed, doing the same amount 
of work - so yes, the amperage will go up as the voltage goes down. Your 
explanation is a bit long, but it is completely correct. Your water 
analogies help explain things. Some of the statements given in previous 
posts are implying that a loose connection will cause higher amperage. 
Ohms Law says this is not possible - any restriction in a circuit will 
always cause a voltage drop, and amps must go down.
In a message dated 10/17/2021 12:00:08 PM US Eastern Standard Time, Dave 
Roden writes:

Aside from the action of back EMF, when a motor is running flat out from a 
battery, Ohm's law reigns.  That is, P = E * I or P = E^2 / R.  

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