1.5 pole contactor question.

[theneufeld]

Hello everybody,
While buying parts for my controller I hastily bought a 1.5 pole contactor instead of a 2 pole. It arrived today and I cannot for the life of me figure out how it works, if at all.

Will this still work or am I going to need to get a different one?

Here is what I got. http://www.ebay.com/itm/221401057982

 

[pumpkin02]

It depends on what you're using it for. It switches one pole and the other passes through unswitched. If you're using it for 240v and need both L1 and L2 switched, then you need a 2 pole.

 

[augiedoggy]

I recently made the same mistake myself... as mentioned for safety reasons you want a 2 pole otherwise you might as well just use the single pole ssr since the one leg could still have the potential... if you switched the oposite leg of power with the contactor it would be safer but still not as safe and ideal as killing both at the same point on the same main relay.

 

[itsnotrequired]

i've always felt the phrase '1.5 pole' is goofy and often leads to more confusion than clarity. i don't believe it is a term defined in any standards and is more of an industry slang. this type of contactor is nice in that it basically includes an integral terminal point to land your unswitched conductor. with a standard single-pole contactor, a user would need to provide their own terminal block or wire nut to continue the circuit. or if using single conductors, a continuous wire between the end devices, bypassing the contactor. with all wiring inside an enclosure, it isn't that big a deal but the 1.5 pole is nice if you have a remote contactor in their own panel.

 

[augiedoggy]

i've always felt the phrase '1.5 pole' is goofy and often leads to more confusion than clarity. i don't believe it is a term defined in any standards and is more of an industry slang. this type of contactor is nice in that it basically includes an integral terminal point to land your unswitched conductor. with a standard single-pole contactor, a user would need to provide their own terminal block or wire nut to continue the circuit. or if using single conductors, a continuous wire between the end devices, bypassing the contactor. with all wiring inside an enclosure, it isn't that big a deal but the 1.5 pole is nice if you have a remote contactor in their own panel.

But as I understand it the potential weakness here would still be one hot leg of power going to the element or remote element plug even when off depending on how its wired which is less than ideal and even if the ssr was wired to the opposite leg the same would be true if the SSR malfunctioned.
the dual pole relay is a more accident proof solution unless I missed something?

 

[theneufeld]

But as I understand it the potential weakness here would still be one hot leg of power going to the element or remote element plug even when off depending on how its wired which is less than ideal and even if the ssr was wired to the opposite leg the same would be true if the SSR malfunctioned.
the dual pole relay is a more accident proof solution unless I missed something?

My knowledge is limited, but if it kills the one line than the circuit should be broken anyways I would think.

If it is usable than my only question is how the heck do I wire it up? Does the switch connect to the middle terminals on either side?

 

[itsnotrequired]

But as I understand it the potential weakness here would still be one hot leg of power going to the element or remote element plug even when off depending on how its wired which is less than ideal and even if the ssr was wired to the opposite leg the same would be true if the SSR malfunctioned.
the dual pole relay is a more accident proof solution unless I missed something?

for 240v, you absolutely want a two-pole contactor to break both hot legs. sure, the circuit wouldn't work with one leg open but now your downstream stuff is still hot, grabbing it could zap you. these 1.5 pole contactors really only exist for convenience of wiring in the field and the manufacturer able to use the same form factor as a two-pole contactor for ease of fabrication.

 

[augiedoggy]

My knowledge is limited, but if it kills the one line than the circuit should be broken anyways I would think.

If it is usable than my only question is how the heck do I wire it up? Does the switch connect to the middle terminals on either side?

it is broken but sill hot on one line which could be dangerous when cleaning up and say unplugging an element with wet hands if you have a fancy triclover element with a plug on the end like I do... It just leaves a greater possibility for an electrical mishap is all.

 

[itsnotrequired]

assuming a 240v setup, you would wire the incoming black wire to the set of gold terminals on one end and the outgoing black wire to the gold terminals opposite. use the terminals that are both on the same side as the one with the nameplate. repeat for the red wire on the other gold terminals, opposite the nameplate. the silver terminals on the long sides are for the coil, the signal that will open/close the contactor.

with this configuration, the black leg will be interrupted by the contactor opening/closing but the red leg will always be continuous. this is not a very safe setup, you really want to interrupt all hot legs.

 

[theneufeld]

Thanks everybody!