calgaryguy
Chris
I'll give this a shot today sometime. My regular job is getting in the way... LOl
YASMT: Allen Bradley Mag switch wiring for Single Phase
- Thread starter calgaryguy
- Start date
calgaryguy
Chris
Its alive. I took a video, but the forum wont let me upload it. Lol.
Forward/Reverse, stop/start, moving from fwd to middle/rev to middle AND the side cover 'safety switch' all work as intended.
Forward/Reverse, stop/start, moving from fwd to middle/rev to middle AND the side cover 'safety switch' all work as intended.
calgaryguy
Chris
Couldnt have done it wthout you gents, thanks.
Congrats! Well done.
You can use a program called “Streamable.com”. You upload the video onto their platform and then they give you a link which you can post here. The basic version is free.
calgaryguy
Chris
Fyi, you may note that I have the lead screw, saddle and apron removed. No need to panic.
Cleaning and inspection.One last note. I didnt run a ground wire all the way to the motor from the junction box where the incoming line comes in. The incoming line is grounded to the juntion box which is metal and is bolted to the base. This is the way the 3ph motor was configured. Thoughts? Any risks here? My woodworking 220v stuff always has a ground run to the motor via a bond at the mag switch.
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calgaryguy
Chris
It absolutely did. Watch again. 1:06 in.
@calgaryguy Is it my imagination or at 0:36 when you switch in reverse, chuck is rotating in forward direction? (CCW if viewed on end from tailstock).
I couldn't make out the other starts by the time chuck was moving
I couldn't make out the other starts by the time chuck was moving
calgaryguy
Chris
rotations are correct, must be a trick of the camera
Gents
I was about to start a new thread on adapting the wiring of the contactor of my 3 phase (220V, 3/4 HP) SM 1120 to run the 1 phase (110/220) 1 HP motor that came with it but there's so much good background here that it's worth having it all in the same place. I have to say I was pleasantly surprised to find this thread here at home on CHMW!
@RobinHood , I have a question about what you said:
By doing this you bypass the two normally closed switches in the line between L2 and the coil. See diagram above. These appear to be the thermal switches of the two "heaters" and removing power from the L2 line would appear to disable the magnetic coil.
I have read in other resources a suggestion to connect L1 & L3 as you said but take the output from T3 and connect it to L2 (thus powering the coil) and connecting the output of T2 to to contact 1) of the drum switch.
I like this approach because it is the least invasive mod to the existing wiring. Does this make sense or am I missing something here?
Good advice on doing testing without connecting mains power, I'm not a big fan of letting magic smoke escape!
@calgaryguy , thanks for posting the link to the heater data sheet.
D
That is correct.
That is why AB tells us to connect “X2 to L3“ to power the coil.
Now the coil is powered again; plus the latching coil circuit is protected by the motor thermal switches and is de-energized should the motor overheat and thus open the contacts.
I don’t think your “START” button will work in that case as the T3 leg is only powered after the contactor at L3 is closed. The L2 side of the coil needs continuous power for it to energize / stay energized. The AUX contacts at 2-3 perform the latching of the coil circuit to keep all three main contacts closed.
IIRC, the drum switch on the SM1120 is not supposed to “start the lathe”. It is there to select FWD or REV only and to make sure the contactor opens (thus shuts down the lathe) when the operator switches spindle direction without first stopping the lathe with the “STOP” button.
EDIT: just came back from the shop; the drum switch is wired just like I describe above.
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@RobinHood Thanks!
I’ll have to have a closer look for the X2 line, maybe pull the box out so I can get a better look at the connections. Right now, peering in on hands & knees isn’t doing it for me.
Right now the box isn’t connect to anything so it won’t be difficult to pull it out.
D
I’ll have to have a closer look for the X2 line, maybe pull the box out so I can get a better look at the connections. Right now, peering in on hands & knees isn’t doing it for me.
Right now the box isn’t connect to anything so it won’t be difficult to pull it out.
D
OK, I'm back!
I found some time yesterday to have a good look at the wiring and ring it out vs. the SM wiring diagram and I was pleased and even a bit surprised to find that it hadn't been modified over the years. WIN!
A little contact cleaner on the drum & other switches and everything appears happy and ready to convert to single phase.
I also identified the X2 line (not marked....). I will note that AB gave instructions on how to config. the mag switch for 1 phase but didn't mention the motor so a bit more homework was needed.
After sitting down with the SM wiring diagram and the motor connect data (Baldor) I came up with this connection plan:
The proof is in the pudding, it runs! Both directions! No magic smoke released either.
I honestly don't know if all motors are configured/labelled like my Baldor but it would appear to be the same hookup as @calgaryguy found for his and as @Brent H showed on his diagram. I also lucked in with the "heaters" because my machine was already configured to run on 220V so no searching for different heating elements needed.
Next up is to crack open the motor and see what the telltale (scraping?) noise was when it wound down. Probably protesting about sitting around on the shelf too long.
Thanks gents, appreciate the advice.
D
I found some time yesterday to have a good look at the wiring and ring it out vs. the SM wiring diagram and I was pleased and even a bit surprised to find that it hadn't been modified over the years. WIN!
A little contact cleaner on the drum & other switches and everything appears happy and ready to convert to single phase.
I also identified the X2 line (not marked....). I will note that AB gave instructions on how to config. the mag switch for 1 phase but didn't mention the motor so a bit more homework was needed.
After sitting down with the SM wiring diagram and the motor connect data (Baldor) I came up with this connection plan:
The proof is in the pudding, it runs! Both directions! No magic smoke released either.
I honestly don't know if all motors are configured/labelled like my Baldor but it would appear to be the same hookup as @calgaryguy found for his and as @Brent H showed on his diagram. I also lucked in with the "heaters" because my machine was already configured to run on 220V so no searching for different heating elements needed.
Next up is to crack open the motor and see what the telltale (scraping?) noise was when it wound down. Probably protesting about sitting around on the shelf too long.
Thanks gents, appreciate the advice.
D
calgaryguy
Chris
make sure your 'motor starter heaters' in the AB switch are the right spec for your motor/phase. Thats something I had to change up.
Tecnico, if the motor has a fan with a shield around/over it, check that first for making the "noise" when slowing down. Also take a good look around the drive end of the motor and driven shaft/ pulley( belt drive). It save a lot of work (or add some). A chip, etc. maybe rubbing, dragging at various rpms causing noise. Sometimes things move when slowing or speeding up.
Hope fully not a bearing!
Hope fully not a bearing!
Good point, I skipped over that one a bit quickly reconfiguring the wiring. I won't be using the machine for a while yet, at least the existing ones would give a very conservative safety factor!
Now, for the heaters and just to throw it out there for feedback, I have:
- A one HP motor/max 7.4A
- Bulletin 709, Size 00 magnetic switch
- Two relays (not open block type)
This points to Table 13, full loads less than 7.63A so it's looking like I need a N28 heater element.
For ref: AB Bulletin 815
Make sense?
Tks.
D
@Bandit the motor has an integral impeller/fan in the case so perhaps a bit different from what you're thinking. For sure it's not a TEFC. I don't think there are any chips in it either because it's not the (3 phase) motor that came off of the lathe but who knows what else might be in there from it laying around, LOL!
I suspect it might be bearings with old, dried up grease in them but I'm not too fussed about it, it's about what I'd expect after it laying around for years. It's the motor that the previous owner planned on putting on it 30 years ago. As long as it runs now, I can go from there!
D