Electrical current question

[joaks]

I have a basic ohms law question.
At work I have a device which I run electricity through. I can set my power source for constant volts or mAmps. I use constant volts. I can check the level of volts or amps being delivered. So with constant volts if I increase the resistance and look at the amps, should they go up or down? ohms law suggests down but I am not sure because the power supply is changing output to keep my volts the same.

 

[sleddriver]

Down. By increasing the resistance, you're making the load easier on the PS, unless we're talking highly capacitive or inductive loads.

A constant voltage supply will vary current in an attempt to prevent the voltage from dropping, even into a low impedance load....within its own limits of course. Or until the "magic smoke" appears.

A constant current supply will vary the voltage to ensure the current remains steady, even across high resistance connections...within its own limits.

 

[tcp71]

Decreasing. Constant voltage means current is dropping as resistance is increasing. I=V/R. It's the law. Is there any inductive element to the device that is causing question? Strictly DC?

 

[crazyoildude]

This "device" is it an electric chair ?

I would assume down but a little more info would be helpful.

 

[Jetronic]

Originally Posted By: joaks
I have a basic ohms law question.
At work I have a device which I run electricity through. I can set my power source for constant volts or mAmps. I use constant volts. I can check the level of volts or amps being delivered. So with constant volts if I increase the resistance and look at the amps, should they go up or down? ohms law suggests down but I am not sure because the power supply is changing output to keep my volts the same.


the amps are a function of the voltae over the resistance. If the voltage stays the same, the amps go down for increasing resistance.

If you calculate the power output, it goes down the same, because power is voltage * current.