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kengineering
19-02-2006, 02:48 AM
I was called to repair the table saw of a friend. I found the start cap had litteraly exploded in its cover plate. Just a roll of paper and plastic bits. He said the motor had been replaced 2 months ago and had worked fine until yesterday. Any ideas what can cause this? Ken

afeef
19-02-2006, 09:27 AM
I was called to repair the table saw of a friend. I found the start cap had litteraly exploded in its cover plate. Just a roll of paper and plastic bits. He said the motor had been replaced 2 months ago and had worked fine until yesterday. Any ideas what can cause this? Ken


hi
there is 2 reasons i gess
1-the capasitor has factoty defects, bad materials or loos connections
2-the saw is jammed in some times , that increase the current passing thru starting coils , then blows the capasitor
recomondation:make the on-off mode as low as you can , cause every on-off strike the saw consume twise the rated current, and that affect the starting coils and capasitor and shortend there life
all the best
afeef

Peter_1
19-02-2006, 09:32 AM
wrong wired ?

kengineering
19-02-2006, 12:39 PM
I thought it was wired wrong myself but there were a few sets of cabinets cut since replacing the motor and it ran just fine. As far as being stuck I guess its possible but I am told it happened on start-up with no load on the saw. The defect theory may have some teeth. Ken

chillin out
19-02-2006, 02:02 PM
Is it one of them old Brook Crompton motors?

There is a clutch thing at the back of the motor (inside) that switches start/run windings. Check this is ok.

Chillin:) :)

jamcool
19-02-2006, 02:29 PM
check the centifugal switch it might be bad so on start up it stays shut and stays on start not opening to run

Andy
19-02-2006, 04:24 PM
Hi
a capacitor will blow up the nicest you have ever seen if you apply voltage to it the wrong wall (older fixed polarity) or again any capacitor if you apply voltage the wrong way before it discharges.

Kind Regards. Andy:)

kengineering
24-02-2006, 01:45 AM
How do I determine a bad centrifugal switch?
Thanks, Ken

wambat
24-02-2006, 03:46 AM
How do I determine a bad centrifugal switch?
Thanks, Ken


Usually located back end of the motor. I
agree it's probably a defective switch, sometime all you may need is a little lubrication. You will have to remove the back cover on the motor

chillin out
24-02-2006, 10:45 PM
How do I determine a bad centrifugal switch?
Thanks, Ken
Once you take it to pieces you will see if its ok straight away. Contact will be stuck together or blown apart.


Chillin:) :)

kengineering
25-02-2006, 01:13 AM
I will check next week when I visit.
Thanks, Ken