Bridge rectifier issue...

[EFK]

Anyone know anything about bridge rectifiers? I have an amp here that takes 6.3 AC out of the transformer and runs it through a bridge rectifier to convert to DC for the filaments. The original was a wimpy-looking little unit which failed and when I replaced it I went overboard with this:

GBPC1210W Fairchild Semiconductor Bridge Rectifiers

This 12A, @ 80 W dissipation, 1000V: a measly little filament voltage conversion ought to be a piece of cake for this thing. And it is - it does its job. But, I just noticed this and maybe it's nothing, but this sucker gets pretty hot when the amp is running. Not meltdown hot, and the filament voltage doesn't vary, but it's too hot to touch and I don;t remember it being this way when I first replaced it.

Does this seem normal, or should I grab a backup from Mouser and get ready to replace it...

[Tom Phillips]

Seems like it would get pretty hot if it wasn't screwed down to the chassis to suck away the heat.
The forward voltage drop is 1.1V. Multiply by the current you are drawing and you will probably find that there is a lot of power being dissipated in that relatively small package.
It's probably designed to take the heat but you should check out the Derating Curve in the spec sheet.

[EFK]

Hmmm. Didn't think about screwing it to the chassis, as the original was not, but that would explain the hole through the center. Maybe I could screw a block of aluminum to the top of it or something like that....