Start capacitor question- Clarke compressor.

iis_iis said:
...while teaching elec trades ( Electrotechnolgy by nondescript name ), come the class "test equipment" of common sense challenged first year apprentices, batch of beautifully made Hitachi Japan hand crank meggers, yes it was a time back. Knew what was coming, sent the 12 or more meggers into the land of the young male "fun propelled" prospects, deliberately turned my back to them and waited, arghhh scream etc.. could not help themselves zap one another with the 500Vac, after a minute of two they had zapped one another into a semi workable room, akin to the electric chair treatment, spooked one another with ambushes from 500V must zap fellow mozzie, seemed to bring an order if not clear minded attention to the lesson unfolding. Saved me the bother of room discipline, half stuffed the lot of them.

The old charged cappy and thrown to victim gag has a problem, should the lead wires puntcture the insulating skin layer then does not take much to cause fibrilation, not a high probability agreed however is a possibility. Akin to the police using the "non lethal" Taszers, subtotaneous electric current is very dangerous, even microamps if the heart muscle is bridged. Idiotic safe public control, never mind i used to spook the highway patrol mob with their dash mounted K band radar, "known to cause infertility in males when exposed coming off the windscreen..." not long after the later models were gutter mounted i observed, should have kept quiet... let them take their chances. Overall the HP had public saftey as a goal, there was an element whom were there to subjugate riders and drivers, had my share of the latter.... random off topic ramble... birthdays the root cause... j.
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I reckon 500Vdc was your intention (blame the birthdays) :)
Get quite a frightening crack putting 5kV over HV cable while it's still on the drum. That'd keep the kids in line (prostrate)
 
Recollection here was AC Pat, faulty memory nothing to do with me... just tested the hand crank, indeed Pat DC it is with a 30Vac ripple, obliged to you, movie, crappy as you would expect from old person, 3 hands more useful. Reached about 440Vdc. If AC that would be 1.414 times the DC value, cannot do the calculation as my abacus fell off the bench and now does crooked sums, just the thing for the modern money trading world.....j.
 

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I was hoping to learn something about capacitance here. I have changed out quite a few over the last 30 years. To test, I know to short the two contacts to discharge before testing with a multimeter set to uf (capacitance). Motor will not start if low. If a cap is higher value (I've gone 20% higher), then motor runs. Probably not useful info for most here.
 
iis_iis said:
...while teaching elec trades ( Electrotechnolgy by nondescript name ), come the class "test equipment" of common sense challenged first year apprentices, batch of beautifully made Hitachi Japan hand crank meggers, yes it was a time back. Knew what was coming, sent the 12 or more meggers into the land of the young male "fun propelled" prospects, deliberately turned my back to them and waited, arghhh scream etc.. could not help themselves zap one another with the 500Vac, after a minute of two they had zapped one another into a semi workable room, akin to the electric chair treatment, spooked one another with ambushes from 500V must zap fellow mozzie, seemed to bring an order if not clear minded attention to the lesson unfolding. Saved me the bother of room discipline, half stuffed the lot of them.

The old charged cappy and thrown to victim gag has a problem, should the lead wires puntcture the insulating skin layer then does not take much to cause fibrilation, not a high probability agreed however is a possibility. Akin to the police using the "non lethal" Taszers, subtotaneous electric current is very dangerous, even microamps if the heart muscle is bridged. Idiotic safe public control, never mind i used to spook the highway patrol mob with their dash mounted K band radar, "known to cause infertility in males when exposed coming off the windscreen..." not long after the later models were gutter mounted i observed, should have kept quiet... let them take their chances. Overall the HP had public saftey as a goal, there was an element whom were there to subjugate riders and drivers, had my share of the latter.... random off topic ramble... birthdays the root cause... j.
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My memory may be teasing me, but I think that one of the Australian electronics magazines (ETI maybe?) published a project called 'The Hot Seat' which was a competitive reaction time game, required two stools with an electric fence type HV pulse applied to the seated bum. The first to push their switch when a lamp lit up got to apply a shock to the competitor's arse. This must have been in the 1970s, somewhat non-PC. Imagine letting that loose on a class of electrotech trades students.

Or did someone spike my morning coffee with LSD?

cheers,
bazzee
 
They used to do Sociology experiments like this; plenty of people love to exhibit Sociopathic tendencies. The ethics people tend not to like this stuff.
 
bazzee said:
My memory may be teasing me, but I think that one of the Australian electronics magazines (ETI maybe?) published a project called 'The Hot Seat' which was a competitive reaction time game, required two stools with an electric fence type HV pulse applied to the seated bum. The first to push their switch when a lamp lit up got to apply a shock to the competitor's arse. This must have been in the 1970s, somewhat non-PC. Imagine letting that loose on a class of electrotech trades students.

Or did someone spike my morning coffee with LSD?

cheers,
bazzee
Click to expand...

Those games were a daily occurrence at the factory where I worked.

The best was a mesh gangway, when the girls from the packaging line walk underneath for lunch they’d be doused in water, the next station above them as they ran was a 20kg bag of flour 🤣🤣🤣
 
Update- fitted new start capacitor and it fired up immediately! But after running for a minute the Capacitor exploded- POP- and blew the can apart….. I think maybe the centrifugal switch isn’t working? Ideas on a postcard to “ Exploding capacitor Competition”
 
Oh dear…
Yes, could be the switch welded shut. Could be a couple of other things too, including a different motor type.
Disassembly is pretty easy, and I’m sure you’ll be able to work out how the centrifugal switch works. They often polish up ok, like contact points.
Or now that you’ve tried the easy repair, it might be time to take it to a pro who can test it and tell you if it’s worth spending any more time on it. Take the original cap with you.
 
Andy said:
Oh dear…
Yes, could be the switch welded shut. Could be a couple of other things too, including a different motor type.
Disassembly is pretty easy, and I’m sure you’ll be able to work out how the centrifugal switch works. They often polish up ok, like contact points.
Or now that you’ve tried the easy repair, it might be time to take it to a pro who can test it and tell you if it’s worth spending any more time on it. Take the original cap with you.
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Capacitor went off like a firework and puked it’s coil of paper out the end! 😂 Anyway I think it’s actually got a Potential relay that sits in the terminal box as opposed to a centrifugal relay which I had guessed it had. I think the original capacitor died, causing the points to stick on the relay- I’ve now got to work out which bits are sticking before I try ( fry) a new capacitor.
 
Update- I’ve fitted a new capacitor and I noticed the coil spring had popped off the energy relay that keeps the points closed.
Now it fires up but cuts out after a few seconds. The points on the relay are arcing ( I thought the relay opened once the motor started not continually open closing?) The capacitor is getting a bit warm so I’ve stopped! 🤔
 
Exmoor beast said:
Update- I’ve fitted a new capacitor and I noticed the coil spring had popped off the energy relay that keeps the points closed.
Now it fires up but cuts out after a few seconds. The points on the relay are arcing ( I thought the relay opened once the motor started not continually open closing?) The capacitor is getting a bit warm so I’ve stopped! 🤔
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Kaboom! :eek: :ROFLMAO: :cool:
 
Righto, bring it round to my place after work and I’ll sort it out. But bring your tools, I need you to find me another half a horsepower before the bucket GP in a couple of weeks 😉
image.jpg
 
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