Dummy loads for amplifier fault finding

[stj]

Re: Dummy loads for amplifier fault finding

nice

[redwire]

Re: Dummy loads for amplifier fault finding

It's interesting to do some math.
With 1,000W (total) input you have around 35 minutes before the oil heats to 100°C, in a 20L barrel. So 2x500W as well. Water is much better at 105 minutes.
Very few, if any, audio amplifiers are designed to output full power as a sine-wave for long periods of time. It simply costs too much to size heatsinks, power transformers etc for that. Many are not rated for all channels driven, just a single channel.
My old (fanless) home-made gear can do it, but that is a DIY norm for audio power amps.
I hate parties where the crappy cheapy A/V receiver overheats and cuts out or blows up after 1/2 hour. Buzz kill!

[stj]

Re: Dummy loads for amplifier fault finding

water expands and contracts - not good in a can!

[check12]

Re: Dummy loads for amplifier fault finding

Yeah thought about distilled water when putting it together (which is pretty cheap) but got offered the oil free & it gives plenty time ... easy to build in thermometer or pressure releases too but I've never bothered ..

[redwire]

Re: Dummy loads for amplifier fault finding

I think the water volume goes up around 4% from 20-100°C so 20L becomes 20.8L... time for an expansion tank lol. I wonder how those oil-filled electric radiant heaters handle it.
Otherwise it's cooling fans I guess, on larger resistors not immersion heating elements.

[check12]

Re: Dummy loads for amplifier fault finding

5mins @ 6kW is plenty of time for a barrage of tests ...