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B_man_Al · 07-31-2013, 07:14 AM

Tom .. Yes the coil resistance will go up with temperature as I posted in post #34. But because the ballast resistor is made from a special steel wire, it will increase a lot faster with temperature than the copper wire in the coil.

This will also happen with a coil with a built in ballast resistor. But since the two are internal, there is no way to separate the two for measurement purposes.

As posted by BillM, if the ballast resistor increases 300% ( 3:1) with temp, and the coil primary copper wire, only increases 16% over the same temp range, the dominant change will be due to the ballast resistor, though both contribute to the overall resistance change.

07-31-2013, 07:14 AM	#43
B_man_Al Senior Member Join Date: Feb 2011 Location: Ottawa ON Canada Posts: 301	Re: Mallory tech answer to coil/ballast ? Tom .. Yes the coil resistance will go up with temperature as I posted in post #34. But because the ballast resistor is made from a special steel wire, it will increase a lot faster with temperature than the copper wire in the coil. This will also happen with a coil with a built in ballast resistor. But since the two are internal, there is no way to separate the two for measurement purposes. As posted by BillM, if the ballast resistor increases 300% ( 3:1) with temp, and the coil primary copper wire, only increases 16% over the same temp range, the dominant change will be due to the ballast resistor, though both contribute to the overall resistance change.