Starter wiring

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electricalist

electricalist

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dallas tx
I understand the line and load. Is the back terminals on top for the coil ? What are the 2 terminals on the right, one on top and one on bottom?
7d5df73f57cf618c4703afd51d9e6e6f.jpg
 
The two terminals on the right with no connections are an auxiliary contact.
I can't see the others well enough to say for sure but it appears the neutral is connected to
the overload as it should be with a bright yellow from the OL contact to the coil. The other side of the coil I think is another yellow. Apparently a wire control.
 
The block on the right is an aux. contact, which is usually used as a holding contact when a momentary start button is used. As for the coil, it's hard to see, but it likely is the coil wires.
 
From a batswitch where fire controls are there is 1 circuit that feeds a batswitch switched up is normal and down is bypass with a normaly closed relay that opens the normal position load, the normal load goes to a contactor coil as well as line side of another batswitch, load side of that bat switch goes to ,,,lets say L1 on the contactor,,,,the load side of the contactor is the bypass wire from the first batswitch as well as the wire for the coil on the starter...
When batswitch is in normal the second batswitch turn ex fan off and on...fire alarm opens normal circuit by relay,,fire dept can flip batswitch to bypass which feeds coil on starter to get smoke out ,,,
of the 18 fans set up this way 15 have a black on the top of the terminal block on the right and a red on the bottom,when the starter is engaged the black feeds through to the red...
not sure where these are going and not sure what they are for yet.
 
electricalist said:
From a batswitch where fire controls are there is 1 circuit that feeds a batswitch switched up is normal and down is bypass with a normaly closed relay that opens the normal position load, the normal load goes to a contactor coil as well as line side of another batswitch, load side of that bat switch goes to ,,,lets say L1 on the contactor,,,,the load side of the contactor is the bypass wire from the first batswitch as well as the wire for the coil on the starter...
When batswitch is in normal the second batswitch turn ex fan off and on...fire alarm opens normal circuit by relay,,fire dept can flip batswitch to bypass which feeds coil on starter to get smoke out ,,,
of the 18 fans set up this way 15 have a black on the top of the terminal block on the right and a red on the bottom,when the starter is engaged the black feeds through to the red...
not sure where these are going and not sure what they are for yet.
Click to expand...
Is there a question in there???

If yes, for this type of control wiring, text descriptions such as yours leave much to be desired. Got diagram? :D
 
The others replied that the back terminals are the coil. This is what i thought as well. The terminals on the right i was told are auxilary. Not knowing what it means for this application i thought it would make more sense to offer enough information .
My question is what are auxiliary connections for ? Is it to feed something else when engaged?
Thanx
 
electricalist said:
...
My question is what are auxiliary connections for ? Is it to feed something else when engaged?
Click to expand...
As noted earlier, typically used as holding contacts when start control is a momentary-contact pushbutton switch. Operations person pushes in on pushbutton switch, coil energizes and pulls in contactor yoke, auxiliary contacts close creating a loop from one side of control circuit supply to bypass pushbutton switch, so operations person doesn't have to stand there and hold the pushbutton in... :D
 
If the contactor is fed by a on off type switch,then could the auxilary be for maybe back up power. All the auxilary wires on the top terminal are connected and leave the location in a conduit,all the ones on the bottom do the same..One red one black
 
electricalist said:
If the contactor is fed by a on off type switch,then could the auxilary be for maybe back up power. All the auxilary wires on the top terminal are connected and leave the location in a conduit,all the ones on the bottom do the same..One red one black
Click to expand...
I'm not sure what you are asking. Nothing agrees with what I see in the picture... and there are no conductors terminated to the auxiliary contact.
 
Sorry this pic is one of the starters that was moved to a suite next door but didnt have aux wires , which is what my question was about. What do aux terminals do and when..when the coil closes the top aux feeds through to the bottom . i have to trace out the aux wires and see where they go,,just thought i might get an idea of what they could be..thanx
 
electricalist said:
Sorry this pic is one of the starters that was moved to a suite next door but didnt have aux wires , which is what my question was about. What do aux terminals do and when..when the coil closes the top aux feeds through to the bottom . i have to trace out the aux wires and see where they go,,just thought i might get an idea of what they could be..thanx
Click to expand...

The aux contacts open and close when the main contacts open and close. They can be used for anything you want (usually lower amp rating than main contacts) Quite often they are holding contacts, but could also be used to operate a pilot light, or a status input back to a BAS controller, or anything you want
 
The. 5 starters in that space have a black hot to top and a red to bottom so maybe its to monitor when they are in use.
Ill need to make sure if those are specific to that space or all the fans
 
electricalist said:
The. 5 starters in that space have a black hot to top and a red to bottom so maybe its to monitor when they are in use.
Ill need to make sure if those are specific to that space or all the fans
Click to expand...

The aux contacts do just that, they monitor the position of the main contactor. OFF/ON. OPEN/CLOSED. FALSE/TRUE. 0/1 What you do with the information is your choice.
 
ptonsparky said:
The aux contacts do just that, they monitor the position of the main contactor. OFF/ON. OPEN/CLOSED. FALSE/TRUE. 0/1 What you do with the information is your choice.
Click to expand...
Actually sounds like someone before him made the choice. Now its up to him to figure out what that choice was... :happyyes:
 
Smart $ said:
Actually sounds like someone before him made the choice. Now its up to him to figure out what that choice was... :happyyes:
Click to expand...
thats right.
I can usually understand what any wiring method was,is and isnt. In these situations i wont disrupt what i havent located.
Thanks for all the help. Ill post what the aux is when i get to where they go.
 
Off topic but, what's the deal with the two sets of conductors under the line lugs?

Roger
 
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