Power transformer warms up in Standby mode

[heikors]

Hi everyone,

today I noticed that the power transformer of my '82 Marshall JCM 800 2204 warms up in standby mode (= no sound). It's not that much, maybe 30 degrees Celsius (86 degrees Fahrenheit), but I wonder if that's normal, since I think the amp/transformer doesn't have to work that much when being on standby.

When played (at a quite low volume level though), the transformer's temperature rises just a little, to about 38 (100) degrees. Everything else stays quite cool (except for the tubes of course).

Thanks,
Heiko

[toner]

That's nothing to worry about. I don't know what is typical for PT temperatures but even in standby the PT has incoming AC and outgoing bias and heater AC so a little increase in temp should be normal.

[demonufo]

Yep. To add, don't forget the current draw on the heaters is quite considerable too...

[heikors]

Thanks to both of you!
I made a test today, and it actually takes about 3 hours of standby mode until the transformer reaches about 30 degrees, so I think that's totally okay - as you both wrote, even in standby it still has to work, so I think it's okay that it warms up as slowly as it does.

[MajorWatt]

As long as you can't fry your Spam on it, you should be good to go...