You need to bear in mind that power resistors of the
ceramic wirewound, or metal film, variety are heaters.
They are designed to get very hot at their *rated* power.
200C is typical. Most wirewound resistors can be made
to glow red hot without anything more than a little
discoloration. The wire used is typically nichrome
heating element wire.
For safety issues, engineers usually don't want anything
that hot inside of their chassis, but in cases where
they need bulk power dissipation, sometimes they do.
Assuming that these resistors are DC load, resistors,
measure the voltage across the resistor using a dc meter,
and plug that value into Power = V*V/R, and if Power
is less than the resistor's rated value, you are probably
ok. Engineers typically spec their resistors to run at
about 1/2 the manufacturer's rated power.
There is no point in paying for a large power resistor if
you don't need a large power resistor.
-Chuck Harris
On Tue, 09 Nov 2021 04:04:39 -0800 "Richard Merifield"
<coitboy2000@...> wrote:
Thanks Morris, yes I will transfer it over to 240V.
...Before I did so I noticed R30 was
scolding hot like my other unit. I wonder whether they ever
considered high wattage resistors for R30 ?
