motor starter question

[Cord]

I have a single phase 220v motor that I need a starter for. I'd like to have the starter be controlled by a remote switch. At this time I'm not certain if the switch will be momentary or latching. I'd also like the starter to have a disconnect built in so I can kill the power allowing me to work on the machine safely. Per the motor tag it will pull 20.5 amps, so I believe I'll need a 3 phase starter that is rated for 35+ amps. I'm on a budget so I'd like to buy a used starter off of ebay, but I'm not sure what I'm looking for - there are too many options.

The motor has a thermal reset built into it, so does this mean I can bypass the starter heaters?

This one is available locally, would it work? Motor Disconnect Starter - general for sale - by owner

 

[MossRoad]

Why do you need a 3 phase starter for a single phase motor? Just curious as to the use. Thanks.

 

[ch1ch2]

Why do you need a 3 phase starter for a single phase motor? Just curious as to the use. Thanks.

That is my thought too.
How did you jump from 220v to 3 ph.

 

[rodnok]

I have a single phase 220v motor that I need a starter for. I'd like to have the starter be controlled by a remote switch. At this time I'm not certain if the switch will be momentary or latching. I'd also like the starter to have a disconnect built in so I can kill the power allowing me to work on the machine safely. Per the motor tag it will pull 20.5 amps, so I believe I'll need a 3 phase starter that is rated for 35+ amps. I'm on a budget so I'd like to buy a used starter off of ebay, but I'm not sure what I'm looking for - there are too many options.

The motor has a thermal reset built into it, so does this mean I can bypass the starter heaters?

This one is available locally, would it work? Motor Disconnect Starter - general for sale - by owner

Just from reading your query I can tell you do not have the knowledge to do this yourself. Save yourself some headaches and possibly some severe injury by hiring a licensed electrician to do this job.

 

[Stimw]

I have been controlling a 5 hp single phase 240 volt 23 amp 2 stage compressor with a 30 amp breaker for over 30 years.
No motor starter in the circuit.
Have used compressor for hours daily in my business until I retired a year and a half ago.
I used compressor today to blow off Zero-turn mower after cutting grass.

 

[jaxs]

I think he's talking about an inductive pick up relay coupled with capacitor for hard start. Same principle as capacitors commonly used on electric motors except this configuration drop's out when motor amps drop after starting. Deffinatly should have a pro hook it up.

 

[LouNY]

I have a single phase 220v motor that I need a starter for. I'd like to have the starter be controlled by a remote switch. At this time I'm not certain if the switch will be momentary or latching. I'd also like the starter to have a disconnect built in so I can kill the power allowing me to work on the machine safely. Per the motor tag it will pull 20.5 amps, so I believe I'll need a 3 phase starter that is rated for 35+ amps. I'm on a budget so I'd like to buy a used starter off of ebay, but I'm not sure what I'm looking for - there are too many options.

The motor has a thermal reset built into it, so does this mean I can bypass the starter heaters?

This one is available locally, would it work? Motor Disconnect Starter - general for sale - by owner

It will work, and as far as using either a momentary or maintained switch to control this I'll agree with the other poster that you may want some professional assistance on your project.

 

[mbohuntr]

You definitely need an electrician... Yes you can use a 3 phase starter, but why cobble something together. The HEATERS you describe are the thermal overload components in a motor starter bucket. No you are using a piece of this, and that to save some bucks, and not understanding much of it.. Bad combination.

Always use the breaker to safely work on it, and do a meter live dead live check before touching the wires.

A starter uses either a magnetic coil, or solid state circuitry to close when you push the button. Inside the starter, there is a switch we call an (Aux)illary switch that simply means it closes when the motor starts and creates a "seal-in" to latch the motor on. When you push the "off" button, you monentarily cut the power to the switch, opening it up.

Bottom line, GET AN ELECTRICIAN to put a push button rocker switch, or disconnect switch in line and call it good.

https://2.bp.blogspot.com/-w7qCggwb...wiring+with+contactor+and+circuit+breaker.JPG

http://ecatalog.hubbell-wiring.com/ProductInformation/ProductThumbnails/1000x1000/3A/HBLDS6.jpg

 

[LouNY]

The nice thing about using a starter such as the one linked to is the mechanical disconnect which can be padlocked in the off position, which is more secure then turning a breaker off. Also even though it's rare I have had multi-pole breakers hang a leg and stop 220 volt applications but leaving one leg of 110 on the system, makes for a sudden awakening when working on it.
Breaker lock-outs are available but I expect that very few individuals have them and even fewer use them.

 

[mbohuntr]

The nice thing about using a starter such as the one linked to is the mechanical disconnect which can be padlocked in the off position, which is more secure then turning a breaker off. Also even though it's rare I have had multi-pole breakers hang a leg and stop 220 volt applications but leaving one leg of 110 on the system, makes for a sudden awakening when working on it.
Breaker lock-outs are available but I expect that very few individuals have them and even fewer use them.

We see breakers with a hot leg frequently.. some loads simply do not get their breakers cycled like they should. I always check it dead anyway, it's a habit I like to keep..

 

[Cord]

The nice thing about using a starter such as the one linked to is the mechanical disconnect which can be padlocked in the off position, which is more secure then turning a breaker off. Breaker lock-outs are available but I expect that very few individuals have them and even fewer use them.

That's exactly where I'm headed. The motor is on a table saw so I want to disconnect the power prior to changing the blade. I used to unplug the machine, but I'm not a big fan of this method on a fixed machine. The breaker is on a different level and quite a distance away so human nature will not have me using it. I figured a machine mounted manual disconnect would be a good way to put some additional convenient safety into the saw.

In the end it was for not. The starter I linked to was 26" long and the table saw only has 23" of clear space so it doesn't fit. If I want to do this, I'll have to go with a separate starter and disconnect. I suppose I could wall mount the disconnect, but for the moment I'm sharing a single outlet between several machines until I get the shop formally laid out. Typically, table saws are installed in the center of the space and not against a wall, so in the final set up, it still won't be near a wall outlet or wall mounted disconnect. This will be the only machine with a mounted disconnect, but I'm thinking this is the way I want to go.

Regarding the use of a 3 phase starter... Many of these used starters are 3ph because they're coming from an industrial application. No reason why you can't use a 3ph starter for a single phase application. You just need to provide a jumper between L3 and T2 so the overload works correctly.

For those of you who would rather call an electrician (or plumber, carpenter, mechanic, etc) than try to figure out how to do something, the more power to you.

 

[mbohuntr]

You seem determined to DIY.. your posts clearly demonstrate you do not understand what your looking at.. at least go on some electrical forums and ask for advice.. I want no part of this..

Good luck..

 

[MossRoad]

Why not just put a locking power switch in the saw? Pretty much all table saws have those.

Six bucks at Home Depot....

https://www.homedepot.com/p/POWERTE...BEgIMGfD_BwE&dclid=CM6ehNWFvdwCFQm_wAodo3ACbA

 

[MossRoad]

That's exactly where I'm headed. The motor is on a table saw so I want to disconnect the power prior to changing the blade. I used to unplug the machine, but I'm not a big fan of this method on a fixed machine. The breaker is on a different level and quite a distance away so human nature will not have me using it. I figured a machine mounted manual disconnect would be a good way to put some additional convenient safety into the saw.

In the end it was for not. The starter I linked to was 26" long and the table saw only has 23" of clear space so it doesn't fit. If I want to do this, I'll have to go with a separate starter and disconnect. I suppose I could wall mount the disconnect, but for the moment I'm sharing a single outlet between several machines until I get the shop formally laid out. Typically, table saws are installed in the center of the space and not against a wall, so in the final set up, it still won't be near a wall outlet or wall mounted disconnect. This will be the only machine with a mounted disconnect, but I'm thinking this is the way I want to go.

Regarding the use of a 3 phase starter... Many of these used starters are 3ph because they're coming from an industrial application. No reason why you can't use a 3ph starter for a single phase application. You just need to provide a jumper between L3 and T2 so the overload works correctly.

For those of you who would rather call an electrician (or plumber, carpenter, mechanic, etc) than try to figure out how to do something, the more power to you.

And there's the confusion... in your first post you said you'd NEED a 3 phase starter(you don't). In this post you say you can re-use a 3 phase starter if you wire it correctly. That's two whole different meanings, and is probably why people think you don't know what you're doing.

Anyhow, I think you're going overkill. Just put that locking switch on it and then figure out your starter needs.

 

[Stimw]

You can buy inexpensive AC disconnects with lockout that you could mount on the wall where the unit is connected.
I have a cheap HF non-contact circuit tester that I use on wiring to be sure!

 

[CobyRupert]

The motor is on a table saw so I want to disconnect the power prior to changing the blade. I used to unplug the machine, but I'm not a big fan of this method on a fixed machine. The breaker is on a different level and quite a distance away so human nature will not have me using it. I figured a machine mounted manual disconnect would be a good way to put some additional convenient safety into the saw.

A "starter" is a contactor with motor overload protection (i.e. "heaters").
A "combination starter" is a starter with disconnection means (this can be a fused or non-fused disconnect switch or a circuit breaker).

I understand, from the above, your desire to have a local disconnect switch (lockable), but why do you need a starter?
Doesn't the saw have it's own switch?
Or does it just start when you plug it in?

Not sure of your background, so don't be insulted, but you use a starter (contactor) to stop and start a motor (typically when the voltage or amps are too large to directly switch, or you want the switch to be at a remote location etc..). Starter contactors aren't used to electrically isolate (i.e. lock out ) the motor from it's power source when doing maintenance or changing blades.

 

[MossRoad]

A "starter" is a contactor with motor overload protection (i.e. "heaters").
A "combination starter" is a starter with disconnection means (this can be a fused or non-fused disconnect switch or a circuit breaker).

I understand, from the above, your desire to have a local disconnect switch (lockable), but why do you need a starter?
Doesn't the saw have it's own switch?
Or does it just start when you plug it in?

Not sure of your background, so don't be insulted, but you use a starter (contactor) to stop and start a motor (typically when the voltage or amps are too large to directly switch, or you want the switch to be at a remote location etc..). Starter contactors aren't used to electrically isolate (i.e. lock out ) the motor from it's power source when doing maintenance or changing blades.

The starter "box" he linked to in his first post had a lockable disconnect lever on the side.