INSTRUMENT RHEOSTAT

How to keep the Cessna 170 flying and airworthy.

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k0al
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Joined: Sun Nov 14, 2004 12:33 am

INSTRUMENT RHEOSTAT

Post by k0al »

Does anyone have the wattage and resistance of the Instrument lighting Rheostat listed as p/n 0413126? My IPC lists the part number and gives the value of the little compass light series resistor, but no value for the rheostat.

My rheostat is evidently dead as I have one position where I have essentially full brightness and all other positions yields darkness.

Al N5454C
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wa4jr
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Joined: Mon Apr 29, 2002 2:44 am

Post by wa4jr »

I've got one sitting here waiting to be installed. I think mine came from Aircraft Spruce, but can't remember. It is an Ohmite RSH8R0 rated at 1.767 amps with a resistance of 8 ohms. I think the wattage rating is 25 watts. I know there is a formula out there to find the wattage rating based upon the voltage and current, but I can't find it at the moment. Hope this helps. :)
John, 2734C in Summit Point, WV
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cessna170bdriver
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Post by cessna170bdriver »

That rheostat will draw rated current and power at 14.14 volts.

Miles
Miles

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GAHorn
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Post by GAHorn »

In a previous discussion of this subject I posted:
If you're a REAL frugal person, you might find that if your rheostat has failed to either full ON or full OFF (with no dimming controllability) that you can still save your existing rheostat by simply removing the wire connection from one end of the wire-wound resistance wire terminal, ...and resoldering the wire to the OPPOSITE end terminal. This might be due to the resistance wire having broken at the terminal end being previously used....while at the opposite end still being serviceable. The only downside is that the knob will rotate in the opposite direction than previously when dimming/increasing lamp brilliance. (This may not work quite as satisfactorily if you've modified it with epoxy as mentioned previously, however.)



Check out the previous discussion
http://www.cessna170.org/phpBB2/viewtop ... t&start=15
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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