Whole Shop And Machine-specific Help For Dunce

So I've been looking around for switches... Obviously, I want round face push-buttons that fit snuggly in a 30mm hole. Illuminated switches would be nice. What switching mechanism is appropriate here? I wouldn't want to use momentary switches for these, right?
For machine control you are usually controlling latching contactors and want SPDT momentary switches. Looks like you've already got some in that panel. How are you going to use the switches?
 
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For machine control you are usually controlling latching contactors and want SPDT momentary switches. Looks like you've already got some in that panel. How are you going to use the switches?

John, yeah, there are some there, but they're pretty beat up. I'm thinking about replacing the works and be done with it.

For the motor starter you will want momentary, Start, Normally Open (NO), for the Stop, Normally Closed (NC)
For the Estop, Maintained, Twist release, NC
For the lamp and coolant pump, Maintained Selector, NO

Try this
https://www.automationdirect.com/adc/Shopping/Catalog/Pushbuttons_-z-_Switches_-z-_Indicators

Nice. Thanks Jim! So what I need:
I'm going to need that "master" power circuit to activate the controls. I figure something with an amber light, or at least an amber indicator?
I'm going to need a green button, and a red button.
I'm going to need blue for coolant.
Lamp can be plain/white.

The E-Stop button will need to be linked to that Stearns Brake, so I assume the way that will work is pulled out, the circuit will be closed, permitting the brake to be disengaged, and when I push it in, it will open, and the brake gets applied. Or maybe I'm making it too simple. Will I need to put a relay in place? The next question along those lines... One of the things I read that is a recommendation for lathes over a certain bed length is to have TWO E-stop switches... One at the Headstock somewhere in easy reach, and one mounted in easy reach on the carriage. So follow my ignorance a step further. Is the way to do this approximately like: The two E-Stop switches are in series, and if either is pushed-in (Open) then that breaks the circuit that energizes the relay that when energized, sends power to the brake, which then disengages? Roughly?

I've been looking at coolant systems just because. What I've decided is that I ought to provision for a 3 phase coolant pump, probably in the 1/8-1/4HP range, that would be electrically integrated to the machine, via an accessory socket like the one the machine already has... Anything less than that, I can do as an adjunct free-standing circuit separate from the machine anyway... Sound reasonable?

So the idea, I think, would be like this:
Turn on "master" (Control circuit) power which would be my separate 120v circuit. This should then do the following:
Turn on an indicator
Enable the E-Stop Circuit (Provide power to a relay for the the brake to disengage it) and I assume stops the main motor.
Enable the Starter Circuit (Provide power to the starter button)
Enable the Pump Circuit(Provide power to the Pump Switch)
Enable the Lamp Circuit(Provide power to the lamp switch)

At that point, hitting the E-Stop switch should de-energize the relay, and the brake should apply.
Pressing the Starter button should power up the main motor
Turning on the Pump Circuit should power a relay to power the accessory plug(3-phase)
Turning on the Lamp circuit should just turn on a 120v lamp socket.

Once the motor is running, does the stop switch break the main motor circuit, or how does that work exactly?

Sorry, I'm just trying to work all this out in my head, and there's plenty of bone to penetrate...
 
I'm going to need that "master" power circuit to activate the controls. I figure something with an amber light, or at least an amber indicator?

A lighted pushbutton would be my choice here.

The two E-Stop switches are in series, and if either is pushed-in (Open) then that breaks the circuit that energizes the relay that when energized, sends power to the brake, which then disengages? Roughly?

Yes, wired in series. Pushing in either E-stop would deenergize the Control Power (master) circuit, and thus deenergize the brake

What I've decided is that I ought to provision for a 3 phase coolant pump, probably in the 1/8-1/4HP range, that would be electrically integrated to the machine, via an accessory socket like the one the machine already has...

To add in a 3PH coolant pump, you will need to add a small motor starter and related circuit.

So the idea, I think, would be like this:
Turn on "master" (Control circuit) power which would be my separate 120v circuit. This should then do the following:
Turn on an indicator
Enable the E-Stop Circuit (Provide power to a relay for the the brake to disengage it) and I assume stops the main motor.
Enable the Starter Circuit (Provide power to the starter button)
Enable the Pump Circuit(Provide power to the Pump Switch)
Enable the Lamp Circuit(Provide power to the lamp switch)

The E-stop drops out the control power so everything is deenergized. You would have to push the control power button after an E-stop to start again.

I would put the work lamp ahead of the control power relay as shown in the schematic, that way you can turn on the work lamp even if the E-stop is pushed. Other than that, I think you've got it.

Once the motor is running, does the stop switch break the main motor circuit, or how does that work exactly?

Yes, the motor stop switch is wired in series with the ''seal in'' contacts in the motor starter. So pushing the stop button deenergizes the motor starter.
 
A lighted pushbutton would be my choice here.

Hmm. I was looking at the site you linked earlier. I like the look of the Cutler Hammer switches and so on. A bit more pricey, but I think they look like they might be reasonably sturdy. Any tips on that front? Also, I noticed all their illuminated pushbutton switches seem to be momentary, except for the mushroom head type, which they only have red and green in illuminated. Maybe I missed some... Wouldn't be the first time. Thanks for the tip though, as it was certainly better than some I'd been looking at.

Yes, wired in series. Pushing in either E-stop would deenergize the Control Power (master) circuit, and thus deenergize the brake

This raises another question. Don't take it overly seriously, but I wondered: Could I make a brake switch that would 1.) stop the motor and 2.) apply the brake without killing master power? I wonder this in the instance in which I want to stop the spindle, but not cut the power, and here I'm thinking about threading operations. I realize this would complicate matters... Mostly spit-balling.


To add in a 3PH coolant pump, you will need to add a small motor starter and related circuit.
Right, I could put in the front end for now, maybe omit a fuse, and come back and add the pump and starter later? Here, I am just considering running the switch wiring for now even if it does nothing until some future date. I've looked at how I'm going to need to run wires, and think it would be best to do so if possible.

The E-stop drops out the control power so everything is deenergized. You would have to push the control power button after an E-stop to start again.

Right, and this is why I asked what I did about a separate braking function.

I would put the work lamp ahead of the control power relay as shown in the schematic, that way you can turn on the work lamp even if the E-stop is pushed. Other than that, I think you've got it.

Makes sense to me. Glad I'm starting to understand the chore at hand. It's really not that complex. It's just that I want to build it once, build it right, and be done.

Yes, the motor stop switch is wired in series with the ''seal in'' contacts in the motor starter. So pushing the stop button deenergizes the motor starter.

See, this is where my unfamiliarity with 3 phase motors and their starters really hurts me. I'll have to see how that is all wired once or twice to start to absorb it. Nothing like hands-on.... I know, I know, my string of questions would never indicate I design and simulate circuits like this one:
amp_schem.jpg
Thanks for your patience and help, Jim!

Mark
 
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Hmm. I was looking at the site you linked earlier. I like the look of the Cutler Hammer switches and so on. A bit more pricey, but I think they look like they might be reasonably sturdy. Any tips on that front? Also, I noticed all their illuminated pushbutton switches seem to be momentary, except for the mushroom head type, which they only have red and green in illuminated. Maybe I missed some... Wouldn't be the first time. Thanks for the tip though, as it was certainly better than some I'd been looking at.
They have all the normal colors, you just need to spend some time browsing. ;) Be careful of what you order, you want to make sure you get the operator and the contact block. Cutler Hammer is top of the line NEMA rated products, but certainly not cheap. I only buy from industrial electrical vendors, trying to by off of Ebay or something like that is a PITA. I want the full product catalog with all of the specs and documentation to go through when I buy. Besides orders over $49 get free 2 day shipping.:)


This raises another question. Don't take it overly seriously, but I wondered: Could I make a brake switch that would 1.) stop the motor and 2.) apply the brake without killing master power? I wonder this in the instance in which I want to stop the spindle, but not cut the power, and here I'm thinking about threading operations. I realize this would complicate matters... Mostly spit-balling.

Sure, anything is possible. But I think your spindle is engaged with a clutch, so that would have to remain engaged for the motor brake to work. This would not really be a good way to stop a lathe. It is also possible that there is a mechanical brake in the spindle clutch system, not sure.

Right, I could put in the front end for now, maybe omit a fuse, and come back and add the pump and starter later? Here, I am just considering running the switch wiring for now even if it does nothing until some future date. I've looked at how I'm going to need to run wires, and think it would be best to do so if possible

I would just put the switch on the front panel, and run the wires into the electrical cabinet. Then later, you can add the pump motor starter if you want.

That schematic looks kinda like a DC motor controller, looks like it has an H-Bridge in it. I can't see the text well enough to tell for sure.
 
They have all the normal colors, you just need to spend some time browsing. ;) Be careful of what you order, you want to make sure you get the operator and the contact block. Cutler Hammer is top of the line NEMA rated products, but certainly not cheap. I only buy from industrial electrical vendors, trying to by off of Ebay or something like that is a PITA. I want the full product catalog with all of the specs and documentation to go through when I buy. Besides orders over $49 get free 2 day shipping.:)




Sure, anything is possible. But I think your spindle is engaged with a clutch, so that would have to remain engaged for the motor brake to work. This would not really be a good way to stop a lathe. It is also possible that there is a mechanical brake in the spindle clutch system, not sure.



I would just put the switch on the front panel, and run the wires into the electrical cabinet. Then later, you can add the pump motor starter if you want.

That schematic looks kinda like a DC motor controller, looks like it has an H-Bridge in it. I can't see the text well enough to tell for sure.
Jim,

Thanks! I will dig around some more. The Eaton-Cutler-Hammer pieces sure look worth the money, relatively speaking. Should be worth my trouble and expense. I thought about putting one of their rotating red beacons up top for when the motor is running. An expensive option, and a little "bling," but hey, safety first...

As far as my brake question, I wondered about that: if I've got the load spinning, engage the brake, that would probably hammer the clutch, since the motor drive would be stopping but the inertia of the load would still be turning against the holding capacity of the clutch. Makes me wonder about the EM brake with which this was fitted from factory. I'm wondering if that brake was "after" the clutch, or before it in the gear chain. In other words, if the clutch was disengaged so the load is free-spinning, and that brake was applied, did it stop the load or the motor? I'll have to look at the gear case again to figure that out. I suspect it was linked to that e-stop switch, so it may be on the drive side of the clutch, rather than the driven side, if that makes sense.

My schematic there is a heavily modified audio power amplifier circuit. The original is a Soundcraftsmen amplifier of early-mid 80s vintage. My simulations with LTSpice are aimed at reducing THD for the amplifier to below .001% across its range. That particular iteration of my redesign got it down to < .0004%. I own several of these amplifiers. They're amazingly durable, and one corner of my shop will be dedicated as an electronics test bench with my distortion analyzer(s) and o-scope and so on. The circuit pictured here represents a single channel of the amplification circuit, and outputs a maximum of around 500w into a 4ohm load. Two such circuits per unit. They drive my big Polk SRS speakers, which will dissipate 1000w each @4ohms nominal impedance. They get bi-amped. (Two amplifiers driving the load, split high freq and low freq).

So when I decide to shake my rinky-dink shack, it gets a little loud.

Thanks!

Mark
 
Jim,

Thanks! I will dig around some more. The Eaton-Cutler-Hammer pieces sure look worth the money, relatively speaking. Should be worth my trouble and expense. I thought about putting one of their rotating red beacons up top for when the motor is running. An expensive option, and a little "bling," but hey, safety first...

As far as my brake question, I wondered about that: if I've got the load spinning, engage the brake, that would probably hammer the clutch, since the motor drive would be stopping but the inertia of the load would still be turning against the holding capacity of the clutch. Makes me wonder about the EM brake with which this was fitted from factory. I'm wondering if that brake was "after" the clutch, or before it in the gear chain. In other words, if the clutch was disengaged so the load is free-spinning, and that brake was applied, did it stop the load or the motor? I'll have to look at the gear case again to figure that out. I suspect it was linked to that e-stop switch, so it may be on the drive side of the clutch, rather than the driven side, if that makes sense.

My schematic there is a heavily modified audio power amplifier circuit. The original is a Soundcraftsmen amplifier of early-mid 80s vintage. My simulations with LTSpice are aimed at reducing THD for the amplifier to below .001% across its range. That particular iteration of my redesign got it down to < .0004%. I own several of these amplifiers. They're amazingly durable, and one corner of my shop will be dedicated as an electronics test bench with my distortion analyzer(s) and o-scope and so on. The circuit pictured here represents a single channel of the amplification circuit, and outputs a maximum of around 500w into a 4ohm load. Two such circuits per unit. They drive my big Polk SRS speakers, which will dissipate 1000w each @4ohms nominal impedance. They get bi-amped. (Two amplifiers driving the load, split high freq and low freq).

So when I decide to shake my rinky-dink shack, it gets a little loud.

Thanks!

Mark
Oh, two other quick things:
Remember my door safety switch? Ought I fix that as well?

As far as the question of a mechanical brake, not sure how that would work on this beast, if present. I guess another reason to take another look in the gearcase. Dang, that lid is heavy....LOL

Thanks!

Mark
 
Oh, one last thing, not electrical: I figured out that this beast requires change gears as other speculated. There are no additional gears present. (Bummer) The gears on it are for metric. We're investigating through that German outfit if the other gears are available. Particularly, the 115T and 60T that would permit cutting imperial threads... Basically, it uses 3 59T gears, a 118T and I think the other is an 86T to cut metric threads. To go to imperial, you replace one of the 59s with a 60, and the 118 with the 115.

For the other two thread types supported, it requires three other gears, best I can discern.

I'm not so concerned with DP ore modulus threads, but the imperials, why yes, of course!
 
Very cool amp. OK, it makes sense now, what I took to be an H-bridge is actually a push-pull amp. I have never worked on audio electronics.;)

I guess I wouldn't worry too much about the door switch for a home shop, unless you are prone to sticking your fingers into moving gears:grin:

My Jet lathe has a mechanical brake that is applied by a foot pedal. When applied, it drops out the motor contactor. But I have never used it, and the linkage has been removed.
 
Very cool amp. OK, it makes sense now, what I took to be an H-bridge is actually a push-pull amp. I have never worked on audio electronics.;)

I guess I wouldn't worry too much about the door switch for a home shop, unless you are prone to sticking your fingers into moving gears:grin:

My Jet lathe has a mechanical brake that is applied by a foot pedal. When applied, it drops out the motor contactor. But I have never used it, and the linkage has been removed.

Thanks Jim!

Sorry for the late reply. Was busy through the weekend getting ready for Monday's concrete pour. It went okay. More room for my shop now, and a slab ready for machines.

I wondered, given something 4GSR said, if I couldn't build a brake using that shaft on my Martin. Maybe a foot-operated hydraulic brake? I'd have to do the same thing, dropping out the main motor, but that just makes sense. I figure something could be adapted, Ken having mentioned ATV brakes or similar. That would probably work, but the hard part will be the splined rotor hub, I suspect.

More to think about...
 
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