The red button is a thermal protection device that is designed to open when
the air passing over it (motor heat) reaches a set temperature. This
prevents further temperature rise, and protects the motor's wiring
insulation.
The TP thermal protection button/switch won't reset until the motor cools
down to a reasonable temperature, so if the motor gets hot and the TP opens,
pushing the reset button won't reset the TP if the motor hasn't cooled
sufficiently.
Testing the TP can be done with an ohm meter or a battery powered continuity
tester. A continuity test is only to be done on circuits or parts with no
power applied.
An ohm meter check will show very low (near zero ohms) resistance, and the
continuity tester will light if the TP is closed, as it should be, at room
temperature.
If the TP has failed, you can probably get a suitable replacement at a motor
repair shop. There is most likely a temperaure marked on the part itself,
indicating the temperature rating.
For your extension cord, longer cords should always be a larger gage than
the power cord for motor powered equipment and other moderately heavy
loads.. heaters, welders, pumps etc.
Old extension cords can have loose terminal screws, weak contact pressure
and broken strands.
If the motor's centrifugal switch is making good contact, has a good start
capacitor and the TP is closed, and the motor doesn't start with the proper
voltage applied.. then it's very likely that the stator windings are damaged
assuming all other connections are secure).
If the stator windings are damaged, it's not going to be cost effective to
have the motor repaired.
If the pressure swich is faulty, that's a separate issue as far as
troubleshooting the motor (but you said it's been bypassed).
Check TP continuity.
Confirm that the centrifugal switch contacts are closed.
Motor should run with proper voltage.
Confirm that the new capacitor isn't faulty.
If you're uncertain of any of these comments, have an experienced and
qualified person check these items for you.
--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html
"dave" wrote in message
...
sprayed some welder tinware out in the yard, started cleaning the gun
afterward, notice pressure getting low, but I'm still plugged in, checked
everything...
a day later: bypassed the on/off switch, then bypassed that AND the
'blowoff' switch thing too ("for good measure"), still no go/all still VMB
(very much bricklike).
ordered, bought (and waited for) then installed, today, the new 'mcmaster'
capacitor (recommended here, thanks guys :-), but -still- no good. and,
yeah, I just 'assumed' the old capacitor was bad...(though "hoped" might
be the better word)
see some of the compressor glamor, or "lack thereof" at my site:
http://machines.2x.nu/air_compressor_krapped_out/
motor still belly-up, even with the new capacitor installed. what's the
reset button SUPPOSED to do and how do I know if it WORKS? tried that,
too, of course, to no avail. feels like a spring-loaded button pressing
against a steel plate "all ahead dead stop" or some damn thing.
tested the incoming 'hots', and they're live (neon test light) and the
electric is likewise live where the tiny spades push onto the motor male
spade connectors, inside the tiny stomach-shaped motor end-cap. they're
tight there, too. had that entire endbell off the motor a few days ago
too, to 'look it over in there' a bit: centrifugal switch contacts have
been lightly sanded (280 wet and dry/used dry) then cleaned with lacq
thinner on paper, so they're clean. functionally looks OK, motion and
slides good, no busted springs, all groovey. we're "good to go" in there.
get the motor specifics in this image:
http://machines.2x.nu/air_compressor...os/photo5.html
freakin' motor. need this thing. got some die grindering to do
'yesterday'. this *SUCKS*
one of those ol' craftsman "4 hp" motors with the 5/8ths shaft. 15 amp,
1.0 SF, 3450 RPM, capacitor start (but not capacitor run), single phase,
made by goulds-Century. needs to run Counter-C'wise when viewed facing
shaft end. probably cheaper to buy a 'new' (used) compressor COMPLETE than
a motor for THIS one. maybe we can work a swapfest?
if you have time to burn, see my "air compressor KRAPPED OUT" movie, too:
http://www.youtube.com/watch?v=TvmDd1nvdd0
anybody got an old "electric motors - troubleshooting them by their
symptoms" book?
thanks guys :-/
toolie the perplexed