RE: terry's nst filter:power res overheating?

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Ted Rosenberg by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Ted.Rosenberg-at-radioshack-dot-com>

Terry: Once the haunt season is complete, I will take a photo of the new
double decker board and send it to you so perhaps others will benefit from
the slightly modified design (the separate MOV bolt-on strip) and the stand
off arrangement.

Thanks

Ted

<snip>

They should be
mounted off the board preferably screwed to standoffs.  Keep them away from
poly caps!

http://hot-streamer-dot-com/TeslaCoils/MyCoils/BigCoil/protection.jpg

http://hot-streamer-dot-com/TeslaCoils/Misc/NSTFilt.jpg

http://hot-streamer-dot-com/temp/270_series.pdf

Cheers,

	Terry


At 09:49 AM 9/18/2002 -0400, you wrote:
>
>Actually, this is completely wrong.  Although "some" power resistors can
>heat to the point where they glow red, there are a large number of power
>resistors which CANNOT take these type of temperatures.
>
>Also, although a resistor may be able to take 350C, the components or
>enclosure around it may not.  For example, 350C will definitely damage a
>FR-4 board and unsolder nearby components.
>
>Dan
>
>
>
>Hi Larry,
>
>Power resistors are basically space heaters.  At full power they can run
>350C or slightly glowing hot!  I use much larger power resistors than
>needed to keep the temp fairly sane but they will still get hot for sure.
>The heating you see is perfectly normal.
>
>Cheers,
>
>	Terry
> 
>
>At 01:25 AM 9/18/2002 +0000, you wrote:
>>I wired the unit up tonight.  less interferrence than the choke filters i 
>>was using. coil output seems slightly better.  but the problem is the
power
>
>>resistors are heating up a bit more than I would like.  I am using
>>2 12kv 30ma nsts.  my gap is way maxxed out at somewhere just under 1/2".

>>I'm assuming that the gap being wider than it should is probably causing 
>>overheating. the power resistors after 10mins of testing were about
110-120
>
>>degrees F.  the safety gap fires occasionally. any ideas?
>>I could post a link to a picture of the board plus the wiring layout i 
>>chose.  none of the other components are showing any signs of heating.
>what 
>>is the limit of the heating of the power resistors? perhaps 150F ?
>>am i just overreacting?
>>
>>larry.
>>
>>
>