Turning on power

Hello. I am wondering how I should go about turning on a lot of power. I have a 60v 40a dc power supply. Should I use a relay or are there toggle switches that can handle this much power? Thanks.

by ilikethings
April 08, 2017

Look for power transistors. There are many options that can solve your problem.

by xtrusion
April 09, 2017

If it is a simple supply you might try a variac on the ac input. http://variac.com/ You can wind the voltage up slowly for a nice soft start. Way back in time our guys decided to use a monster variac but it was so big that when they plugged it into the factory supply the sudden inductive load usually blew the main breaker. It made them a teensy bit unpopular. :-)

by mikerogerswsm
April 09, 2017

Maximum for toggle switch seems to be 16A. Shower switches will do 45A but they look like, um, shower switches.

by mikerogerswsm
April 09, 2017

1 Answer

Answer by mikerogerswsm

If you use a transistor you need to think about the initial current surge to charge capacitors, turn on lamps or start motors, this may be much greater than your steady current. IGBT devices have high pulse current ratings and may be suitable. Here's the datasheet for a low cost IGBT:


+1 vote
by mikerogerswsm
April 10, 2017

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