motor reversing switch

[jetlag]

I am trying to install a reversing control on a boat hoist. The control has up and down momentary buttons. The motor label shows to reverse the motor swap the blue and yellow wires on the motor push on connectors. I used 14/4 wire to send the blue and yellow wire down and depending on which button is used the control sends it back reversed or not reversed polarity to the terminals. Ok all is fine except when a button is not being used the motor hums . I didnt think current went to the motor if the blue and yellow leads were open, it seems now they only go to the start winding and the motor is trying to start on the run windings. The 120 volt is coming in on L1 and L2. to the motor. The switches on here before were not safe because the reversing switch didnt have off position it stayed on up or down and a seperate snap switch turned the power on , and the winch kept running until the snap switch was turned off. If I leave the snap switch there someone will burn they motor if the dont use the buttons right away. Does some one know if this is not a true reversible motor . I didnt think the reversing switch had to control the line in also ?

 

[hillbilly1]

Is this a jog type set up? Where the motor only runs while the button is held down? Then yes, the power will have to be switched off when the button is released. Of course this could be a two winding European motor where two wires are energized for one direction, then to reverse, the other two are energized, but not both sets at the same time.

 

[jetlag]

thanks hillbilly

thanks hillbilly

Is this a jog type set up? Where the motor only runs while the button is held down? Then yes, the power will have to be switched off when the button is released. Of course this could be a two winding European motor where two wires are energized for one direction, then to reverse, the other two are energized, but not both sets at the same time.

No this is a 3/4 hp 120 volt. It doesn't need to jog , it only runs when a button is held down . But it is suppose to stop if you let off. It is doing that but the motor hums until another button is pressed. I dont see how I can kill the power to the motor when the reversing switch is not being used. Is the line wire suppose to go through the switch some way so it breaks in the off position .
This is not a capacitor start motor , it is an induction start , induction run with a cut out switch.

 

[hillbilly1]

That is jogging.

 

[dicklaxt]

Usually small reversing AC hoists are dual winding , 3 wire motors ,Up,Down(forward,reverse) and common with two momentary pushbuttons or a two position selector momentary center off.

There should not be a hum under that control logic,,,,,,,,,,,,,,,,

dick

 

[hillbilly1]

Usually small reversing AC hoists are dual winding , 3 wire motors ,Up,Down(forward,reverse) and common with two momentary pushbuttons or a two position selector momentary center off.

There should not be a hum under that control logic,,,,,,,,,,,,,,,,

dick

That's what I'm thinking.......unless somebody has changed the motor out with the wrong one.

 

[Smart $]

No this is a 3/4 hp 120 volt. It doesn't need to jog , it only runs when a button is held down . But it is suppose to stop if you let off. It is doing that but the motor hums until another button is pressed. I dont see how I can kill the power to the motor when the reversing switch is not being used. Is the line wire suppose to go through the switch some way so it breaks in the off position .
This is not a capacitor start motor , it is an induction start , induction run with a cut out switch.

Sounds like it needs "held" reversing switch (i.e. like the old switch) and a momentary run (i.e. jog) switch.

 

[ronaldrc]

Some of the smaller 120VAC Hoist motors are also DC motors controlled with a double pole double throw switch.

 

[texie]

I am trying to install a reversing control on a boat hoist. The control has up and down momentary buttons. The motor label shows to reverse the motor swap the blue and yellow wires on the motor push on connectors. I used 14/4 wire to send the blue and yellow wire down and depending on which button is used the control sends it back reversed or not reversed polarity to the terminals. Ok all is fine except when a button is not being used the motor hums . I didnt think current went to the motor if the blue and yellow leads were open, it seems now they only go to the start winding and the motor is trying to start on the run windings. The 120 volt is coming in on L1 and L2. to the motor. The switches on here before were not safe because the reversing switch didnt have off position it stayed on up or down and a seperate snap switch turned the power on , and the winch kept running until the snap switch was turned off. If I leave the snap switch there someone will burn they motor if the dont use the buttons right away. Does some one know if this is not a true reversible motor . I didnt think the reversing switch had to control the line in also ?

These are typically just simple motors with a run winding and a start winding that includes a start cap and centrifugal switch. The on/off switch has to open (be ahead of) both the start and run winding. Otherwise when you set the forward/reverse switch the start winding will get voltage even though you don't have the on/off switch closed because the centrfugal switch on the motor is closed when at rest. We used to do these with a maintained DT switch crosswired for forward/reverse and a momentary contact switch for run (jog). This way an operator could not walk away with it running.

 

[kwired]

If it is a two winding AC motor as described (start and run winding) you can do the reversing with four leads and a double pole double switching arrangement, but you still need one more switch or contactor pole that simultaneously closes for both directions for the run winding.

 

[dicklaxt]

Hey Jetlag,I'm curious about what the specs are on that particular motor and what all the control switches are in total.I love to play with control diagrams,,,,,

dick

 

[jetlag]

Thanks Texie

Thanks Texie

These are typically just simple motors with a run winding and a start winding that includes a start cap and centrifugal switch. The on/off switch has to open (be ahead of) both the start and run winding. Otherwise when you set the forward/reverse switch the start winding will get voltage even though you don't have the on/off switch closed because the centrfugal switch on the motor is closed when at rest. We used to do these with a maintained DT switch crosswired for forward/reverse and a momentary contact switch for run (jog). This way an operator could not walk away with it running.

This is basically what they had already but they failed to use the momentary contact to cut the power. They had a snap switch to break the hot in on the 120v line and that was not safe. I may have to go back with what you said. I did find I have the wrong reversing push button , a 6 wire drum will reverse the start winding and also breaks the line in off position and should work also . By the way this is a homemade winch and the motor is just a common single phase with start windings.

 

[jetlag]

Thanks Dicklaxt

Thanks Dicklaxt

Usually small reversing AC hoists are dual winding , 3 wire motors ,Up,Down(forward,reverse) and common with two momentary pushbuttons or a two position selector momentary center off.

There should not be a hum under that control logic,,,,,,,,,,,,,,,,

dick

This is not a regular hoist motor , it has to be reversed by changing the polarity on the start windings.

 

[hillbilly1]

This is basically what they had already but they failed to use the momentary contact to cut the power. They had a snap switch to break the hot in on the 120v line and that was not safe. I may have to go back with what you said. I did find I have the wrong reversing push button , a 6 wire drum will reverse the start winding and also breaks the line in off position and should work also . By the way this is a homemade winch and the motor is just a common single phase with start windings.

That explains a lot, an easy way to fix it without having to install a drum controller is to use a 4 way switch to swap the start winding with a single momentary switch labeled "RUN" turning power off and on to the whole shooting match. label the 4 way "UP" and "Down"

 

[texie]

This is basically what they had already but they failed to use the momentary contact to cut the power. They had a snap switch to break the hot in on the 120v line and that was not safe. I may have to go back with what you said. I did find I have the wrong reversing push button , a 6 wire drum will reverse the start winding and also breaks the line in off position and should work also . By the way this is a homemade winch and the motor is just a common single phase with start windings.

One other advantage I failed to mention with my setup is that even if the operator changes the for/rev switch while running it has no effect because the centrifugal switch is open at that point. I'd stay away from the drum switch as it is kind of klunky and not panel mountable. Just use a DPDT H.P. rated toggle switch for the for/rev.

 

[jetlag]

thanks dicklaxt

thanks dicklaxt

Hey Jetlag,I'm curious about what the specs are on that particular motor and what all the control switches are in total.I love to play with control diagrams,,,,,

dick

This is a 1725 rpm ,115 v, .75 hp, type SS, fla10.4, continuous duty Marathon shows it as an hvac blower/ fan motor. It has start windings and cut out but no capacitor start. I am trying to attach 2 helpful reversing diagrams but not sure I was able.

 

[kwired]

One other advantage I failed to mention with my setup is that even if the operator changes the for/rev switch while running it has no effect because the centrifugal switch is open at that point. I'd stay away from the drum switch as it is kind of klunky and not panel mountable. Just use a DPDT H.P. rated toggle switch for the for/rev.

They do make 3PDT toggle switches also, and would work great. Use two poles to reverse one winding and the third pole to switch main winding - tie both "throws" together so it is on either direction. Then you have FWD - OFF - REV. Get a momentary switch with center return and you have to hold the switch to operate the motor either direction and it shuts off when you let go.

 

[texie]

They do make 3PDT toggle switches also, and would work great. Use two poles to reverse one winding and the third pole to switch main winding - tie both "throws" together so it is on either direction. Then you have FWD - OFF - REV. Get a momentary switch with center return and you have to hold the switch to operate the motor either direction and it shuts off when you let go.

Yeah, that is another option but I think he will not find that off the shelf though. Maybe Grainger.

 

[kwired]

Yeah, that is another option but I think he will not find that off the shelf though. Maybe Grainger.

I guess I don't think about "off the shelf" that much when doing control work. Even electrical supply house is not all that great for some of these items, Grainger is OK when it comes to selection and availability, usually not the best price though Allied Electronics or Mouser and some motor shops are good sources for a lot of control items. If you are thinking off the shelf from HD or Lowes - you will have to cobble most anything you find from them. If you want to look like you know what you are doing buy something that will look like was done by a pro when all is done.

 

[Smart $]

They do make 3PDT toggle switches also, ...

Yeah, that is another option but I think he will not find that off the shelf though. Maybe Grainger.

Maybe not a 3PDT toggle... but a many supply houses will have a standard 3-position momentary operator and 6 NC contact blocks.