[Pinched wire - hydrogen fuel cell]

Let's say a hydrogen fuel cell has an output of 200 amps at 24 volts. This output is supposed to be isolated from the chassis. Somewhere in the fc is a pinched wire. Measuring from the positive output to chassis thru a 2.5k ohm resister displays 10ma. What is the current rating of the actual short?

by mu34tant
March 30, 2019

ground of 24v battery is connected to chassis.

by wangwg88
April 01, 2019

yes, the test lead has a 2.5kohm resistor in series with the probe. the vmm reads 10ma. what is the actual short current?

by mu34tant
April 01, 2019

24v/2.5k=10ma, so all short current goes through your 2.5k resistor. if you don't connect resistor on, there is no short current.

by wangwg88
April 01, 2019

not true, there is always short current because there is a short

by mu34tant
April 03, 2019

you need to prove that there is a short. otherwise, no short.

by wangwg88
April 03, 2019

no. the short is always there. sometimes the resistor (load) is not present. what I am trying to figure is the maximum current draw across the pinched wire contacting the frame. some short draw more current than others. some draw 1 ma across the test resistor. how can i figure the max current the short will handle from my test?

by mu34tant
April 04, 2019
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