reversing contactors (or motor starters), let's dismantle and modify
 

hi lads

I need a pretty big (normal "non-reversing") three-pole contactor, and
the friggers are pricey. so used is OK. my finished product doesn't have
to pass code or ANY sort of elec'l inspection. I've noticed reversing
contactors sometimes sell for less than 'normal' three pole contactors
on ebay. I need to end up with something in the 'nema size 2' range.
maybe bigger.

I'm thinking I can buy a reversing contactor (or motor starter), remove
any neccessary 'crossbar' connectors and small wires, and end up with a
normal (non-reversing) contactor *plus* some spare contacts and screws,
etc. obviously, I'm not talking about the 'new-fangled' solid-state
contactors here (nor do I want one)

so, that a doable do?

if cutting or grinding (of the phenolic contactor body, or of steel, or
copper bars is involved, I can handle that "no big deal"

please, no 'dire safety warnings' or 'I'm an OSHA dishrag' type replies.
this is just a 'assuming the correct skillset, and the right tools, can
it be done?' type question; I'm not here looking for 'binding legal
opinions' or seeking safety advice

*thanks* guys :-)

Mr Toolie
of the florida swamps

with a tip of the hat to gunner and ig, and all you other regular guys :-)

reversing contactors (or motor starters), let's dismantle and modify
 

"dave" wrote in message
...

-snip-

please, no 'dire safety warnings' or 'I'm an OSHA dishrag' type replies.
this is just a 'assuming the correct skillset, and the right tools, can it
be done?' type question; I'm not here looking for 'binding legal opinions'
or seeking safety advice

-snip-

i like your disclaimer. that should be on file somewhere.

b.w.

reversing contactors (or motor starters), let's dismantle andmodify
 

dave wrote:
hi lads

I need a pretty big (normal "non-reversing") three-pole contactor, and
the friggers are pricey. so used is OK. my finished product doesn't have
to pass code or ANY sort of elec'l inspection. I've noticed reversing
contactors sometimes sell for less than 'normal' three pole contactors
on ebay. I need to end up with something in the 'nema size 2' range.
maybe bigger.

I'm thinking I can buy a reversing contactor (or motor starter), remove
any neccessary 'crossbar' connectors and small wires, and end up with a
normal (non-reversing) contactor *plus* some spare contacts and screws,
etc. obviously, I'm not talking about the 'new-fangled' solid-state
contactors here (nor do I want one)

so, that a doable do?

Generally speaking, there would be no need to cut or grind anything.
The only difference between two separate contactors and a reversing
contactor is that the reversing ones are interlocked to prevent both
sides from being pulled in at the same time. If you only need one side,
you could just ignore the second set of poles and consider it a spare
standby contactor, ready to be swapped in with just a few minutes work.



if cutting or grinding (of the phenolic contactor body, or of steel, or
copper bars is involved, I can handle that "no big deal"

please, no 'dire safety warnings' or 'I'm an OSHA dishrag' type replies.
this is just a 'assuming the correct skillset, and the right tools, can
it be done?' type question; I'm not here looking for 'binding legal
opinions' or seeking safety advice

*thanks* guys :-)

Mr Toolie
of the florida swamps

with a tip of the hat to gunner and ig, and all you other regular guys :-)

reversing contactors (or motor starters), let's dismantle andmodify
 

Stuart Wheaton wrote:
....

If you only need one side,
you could just ignore the second set of poles and consider it a spare
standby contactor, ready to be swapped in with just a few minutes work.

YEAH! now THATS'S what I like to hear. :-) (seems it's as I suspected),
but I sure *DO* appreciate the confirmation

thanks stuart, and thanks to U 2 william :-)

reversing contactors (or motor starters), let's dismantle and modify
 

On Fri, 05 Feb 2010 12:02:57 -0500, dave
wrote:

Stuart Wheaton wrote:
...

If you only need one side,
you could just ignore the second set of poles and consider it a spare
standby contactor, ready to be swapped in with just a few minutes work.

YEAH! now THATS'S what I like to hear. :-) (seems it's as I suspected),
but I sure *DO* appreciate the confirmation

thanks stuart, and thanks to U 2 william :-)

AFAICT it's a "Forward" coil and contactor and a "Reverse" coil and
contactor in the same case, with both electrical interlocking contacts
(to break the other side's coil) and a mechanical linkage between the
two sides, to make doubly sure they can't both pull up at the same
time.

Don't touch anything, just disconnect the cross-over wiring and use
it as a single. The first time it burns a contact you can steal a set
of fresh contact points out of the other side. Second time, you go
get a rebuild kit.

They use the same basic setup as a Delta-Wye "Soft Start" contactor,
with an auxiliary contact or two to handle the Delta-Wye shorting of
the Wye point connections. They use them a lot on frequently started
motors like hydraulic elevator pumps.

-- Bruce --