Discussion in 'The Projects Forum' started by HighVoltage!, Oct 29, 2015.

1. ### HighVoltage! Thread Starter Member

Apr 28, 2014
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0
I have a fairly simple question:

If I was to have a shorted cable thats 4/0, shielded cable through the secondary of a transformer...will that be considered a resistive load (Low resistance because of copper conductor) or capacitive load since its a cable?

The shield is open...only the conductor is shorted.

2. ### #12 Expert

Nov 30, 2010
16,665
7,310
It's a resistor.

Apr 28, 2014
95
0

4. ### #12 Expert

Nov 30, 2010
16,665
7,310
Did you wonder if I was talking about a capacitive resistor? As far as I know, they don't exist.
A resistor makes a resistive load. A resistor does not make a capacitive load or an inductive load unless you get into high frequencies where the shape and length of the wire gets involved with wavelength and parasitic amounts of inductance and capacitance. You said nothing about frequency, so I might still be wrong. Declare this as a gigahertz and all bets are off.

Jul 18, 2013
10,835
2,502
Short circuit secondary that size smacks of a resistance welder!?
Where does the capacitance come in?
Max.

6. ### crutschow Expert

Mar 14, 2008
13,477
3,362
You have the low resistance of the shorted cable in parallel with the shield capacitance.
That effectively shorts the shield capacitance, so the transformer sees only the resistance of the cable.

HighVoltage! likes this.
7. ### #12 Expert

Nov 30, 2010
16,665
7,310
I have some doubts that an un-connected piece of metal is a capacitor of any sort. Did you miss the idea that the shield is not connected to anything or do I need my beliefs adjusted?

Edit: I'm afraid this discussion will run off into, "certain physical configurations and frequencies". Try to work with me in terms of power line frequencies and power frequency transformers.