# 1966 Model a 9 3 phase to single



## Seth (Nov 2, 2020)

Hello all, I have recently purchased a mid 60s model a with and under drive motor. It is a 1/2ho 230/460 3 phase unit which I would like to use on single phase 220. Can someone please point me in the right direction for a VFD or motor replacement?


----------



## Karl_T (Nov 2, 2020)

I've had good luck with this el-cheapo Chinese brand


			https://www.amazon.com/LAPOND-Inverter-Professional-Frequency-VFD-1-5KW/dp/B01DKJWM62/ref=sr_1_4?crid=LPDZCBKCWK5C&dchild=1&keywords=vfd+drive&qid=1604361026&sprefix=vfd%2Caps%2C250&sr=8-4
		


Manual is written in chinglish - hard to understand.  yep this one is way oversized, you could put a bigger motor in later if you need.

if you want top end, look to hitachi VFDs. There are other good ones.








						VFD, 1hp, 4A, 230V, Single Phase, Simple Operation
					

VFD, 1hp, 4A, 230V, Single Phase, Simple Operation, Space Saving, Operator NES1-OP Sold Separately




					www.wolfautomation.com


----------



## Seth (Nov 2, 2020)

I have to admit, I know almost nothing about a VFD and how it’s used. Can you give me the quick rundown for how to install it in line, and how to use it in practicality? I’d greatly appreciate your help.

Moreover, why not just get a 220v 1 phase motor?


----------



## cbellanca (Nov 2, 2020)

3 HP 220 V singlephase


----------



## mopar geek (Nov 2, 2020)

I have a light 10 underdrive.  I used a 3/4 hp single phase motor.  It must be a 56 frame motor to mount up to the original bolt holes of your current motor, and 1725 rpm.  Your plate shows FR  56, so 56 frame size.  A 3 hp motor probably won't fit in an undermount cabinet.  The 56 frame also means that it has the same shaft size, I believe 5/8.  There are some short shaft 56 motors out there as well, .marked 56s. If you have a reversing drum switch, the wiring is a little tricky for a single phase.  I think this is the link I used for a Cutler Hammer switch.  Advantage of vfd is that you get variable speed.https://www.practicalmachinist.com/...-hammer-drum-switch-motor-wiring-question.jpg


----------



## Karl_T (Nov 2, 2020)

A single phase motor would be simpler to install. if it meets your needs you may want to go that way.

Biggest advantage of VFD is variable speed on the motor. Even if you have gear speed changes, you will LOVE this ability.  This is certainly a more complex install. If you feel it will be over your head, you might want to get help.

To give better advice on how to do it yourself, tell me more about how this lathe works electrically. How does it go forward and reverse? is there an Estop?  Motor contactor for the three phase motor? is it a gear change unit for speed changes?


maybe read this:








						VFD control box
					

Here’s a nice little project. I built an enclosure to hold a VFD and controls for my son’s new (to him) lathe. The unit is built so he can just wire 220 1 phase to the VFD and then the 3phase lathe wires to the lathe on the output side. If (when) he trades up in lathes, the box comes right off...




					www.hobby-machinist.com


----------



## Seth (Nov 2, 2020)

It’s only over my head today because its new  to me.   After I get into it, I’m sure I’ll manage.   

Today is the first day I’ve had to focus on getting the lathe running.   Thanks for the info.  

I don’t have the information you asked on the switch.   I didn’t have but a moment with it as the lathe was getting moved.  I will learn tomorrow.


----------



## matthewsx (Nov 2, 2020)

Hello and welcome

Your lathe should be fairly easy to convert to VFD and having the variable speed is definitely a nice feature. You will need a copy of the wiring diagram for your machine, or make one yourself (you'll need a multi-meter if you don't already have one). Then basically you hook the VFD to your single phase 220v on one side and directly to the motor on the other. Control functions are handled by the VFD and can either be hooked to existing switches on the lathe or an external control box.

The most important thing to understand is you cannot have any switches between the VFD and the motor. There are tons of great threads about how to wire one up on here and @mksj  is the resident guru who's threads go into great detail about these systems.

Alternatively you could get a static phase converter like this









						Static Phase Converters
					

Static Phase Converters   A static phase converter is used to generate 3 phase power during the starting of a motor.  A static phase converter consists of one or more start capacitors and a start relay.  The start capacitors produce electricity across the third winding of a motor during start up,




					www.northamericaphaseconverters.com
				




and just hook up the machine to it and use the controls as originally configured. I have both types of converters and either one will get you making chips, just takes a little more effort to wire in the VFD.


John


----------



## matthewsx (Nov 3, 2020)

One other thing, supporting members have access to the Downloads section of this site. I just looked and there's like ten pages of downloads for South Bend machines. Well worth the $10 for silver member status, click on the Donations tab on the top of the page for more info.

John


----------



## Seth (Nov 3, 2020)

So wrapping my head around the VFD IDEA.   I put a start /stop switch in line with the incoming singple phase into the VFD.   The fwd/rev switch is wired through the VFD, which then supplies power to the electric motor?   Seems awfully simple.  What and I missing???


----------



## Karl_T (Nov 3, 2020)

Exactly how to do it depends on what is already there. But yep, you got it.

i normally say you need to add a braking resistor so the lathe stops quickly. Also its best to get an industrial quality speed pot. The one on the VFD is not very durable.  

Its best to mount the VFD inside an enclosure to make it metal chip proof. then its nice to have a way to read the VFD panel.  i've just put a window in a box on some installs. On others get an extension cable for the readout and move it. A gotcha here - the el cheapo VFDs might not do this.


----------



## Seth (Nov 3, 2020)

Nothing is currently there.   The motor is unwired and the switch is in a box.   No safety breaker.  If I use the VFD you recommended, do you have a brake resistor that you like paired with it?


----------



## Karl_T (Nov 3, 2020)

What have you got on the lathe for a forward/off/reverse switch?  I like to use the existing one if at all possible.  If this unit was originally 3 phase, you likely have a drum switch. Going this route we need to BE SURE to program the VFD so it won't start when power is applied and the lathe is already in forward or reverse.  Now if you got Forward and reverse push buttons we'll do it differently.

I have just used a three phase fused switch box on some installs. that's the cheapest.  A VERY NICE step up is to get a motor contactor and an Estop button assembly.  Your call here, the upgrade option adds a layer of operator safety.  

Now I am a cheap a$$. I go on eBay and buy power resistors to make the braking unit. No where as nice as the commercial unit but under $10 vs. nearly $100


----------



## Seth (Nov 3, 2020)

Karl,
Thanks for sticking with me.  It’s my wedding anniversaries today, so I won’t be at the shop until later to have a look at the switch.  I appreciate your time!


----------



## Karl_T (Nov 3, 2020)

You must still be young. We celebrated our 40th by staying in bed a bit longer, and then going out to eat. Rest of the day, I was in the shop she was in her room. 

say, lets have pics inside that left cabinet. looks like the spot for electrical controls


----------



## Seth (Nov 3, 2020)

Karl_T said:


> You must still be young. We celebrated our 40th by staying in bed a bit longer, and then going out to eat. Rest of the day, I was in the shop she was in her room.
> 
> say, lets have pics inside that left cabinet. looks like the spot for electrical controls


I’m 47.  19 years married.    I’ll get you pics ASAP!


----------



## tq60 (Nov 3, 2020)

We used existing drum switch to control vfd.

Clever mod...

Note how wired for return to stock if needed then remove all wires.

Slightly bend the tabs supporting the contacts for ONE set so it connects FIRST for either direction. 

Set vfd for 3 wire control usually...

One wire for run
One wire for reverse
One wire for stop, stop usually needs to CLOSE to run, opening this wire is a safety switch format.

Now wire drum switch with stop on the modified tab section, connect both ways.

Run to connect both ways in another 

Reverse in reverse in last.

If you want to add a foot switch for stop then loop the stop wire through the switch for that, in series so either will stop.

Photos of foot switch and control.

Meter uses an available slave control from VFD to indicate relative speed or load, set to speed.

Sent from my SAMSUNG-SM-G930A using Tapatalk


----------



## Seth (Nov 4, 2020)

Good morning.    Here’s what I found.  










Karl_T said:


> You must still be young. We celebrated our 40th by staying in bed a bit longer, and then going out to eat. Rest of the day, I was in the shop she was in her room.
> 
> say, lets have pics inside that left cabinet. looks like the spot for electrical controls


----------



## Karl_T (Nov 4, 2020)

That can work as a Forward/off/reverse switch. Does not look to be mounted to your lathe?  Its a big bulky son of a gun. I was on ebay last night and seen an allen bradley 3 position for $20.  You might rather use that.  bet you'd get $20 for the switch you got.

will the vfd fit in that lower cabinet?  Good enough position to just cut  a window to see the VFd readout?  If not, take a look again at the thread I linked several posts back. that's how my son did his southbend. It would work very well for you also.


----------



## Seth (Nov 4, 2020)

So help me here. I’ve spent the last hour with a Scotch-Brite pad and a little fine oil and found an awfully nice machine. I really want to use it hard and frequently. Am I wrong to uses such a classic for industrial work?

 With regard to the VFD,  The bulk of the work that I do is drilling and tapping solid stock for shift linkages and weld in bungs. Am I creating more chaos by not just tossing in a single phase motor and a rotary switch?


----------



## matthewsx (Nov 4, 2020)

IMHO these machines were designed to be used hard, make some money with it and when it's time go and buy a new one.

You will definitely want the VFD and it'll probably cost less than replacing the motor. Wire the original switch to the VFD for forward/stop/reverse, add a 10k pot for speed control and a cheap tachometer to know what speed you're running. That's what I did on my Seneca Falls and it transforms these old lathes pretty dramatically.

John


----------



## Seth (Nov 4, 2020)

Thanks for your input.   This machine looks like it was pretty well maintained and lightly used.   So
VFD it is.


----------



## brino (Nov 4, 2020)

Seth said:


> I’ve spent the last hour with a Scotch-Brite pad and a little fine oil and found an awfully nice machine.



@Seth,
The machine looks great!

-brino


----------



## Seth (Nov 4, 2020)

After doing a bunch of research, I’m thinking about this VFD. http://www.electricmotorwholesale.com/9988-KBAC-24D/

opinions?   It’s expensive, but sealed and has the pot built in.


----------



## Karl_T (Nov 5, 2020)

I have no experience with it. If it is durable enough no additional wiring would be needed. it says it all sealed to mount outside.

How do you program it??  is there a fault and program window i don't see?  Does it allow a brake resistor??


<EDIT> scanned the manual. its all done with pots and jumpers - no programming. Looks like braking resistor is not allowed.

My 2 cents. looks like this is designed for applications where it works as set up right out of the box. Hook up power and motor wires and away you go.  the real question: will it work on your machine this way??  i don't know.


----------



## Seth (Nov 5, 2020)

Karl, I was hoping you’d pipe in.   Here’s their description.   

*KBAC-24D Black (9987) AC Drives, Nema 4x Inverter*

The KBAC-24D Adjustable Frequency Drive is a variable speed control in a NEMA-4X /IP-65 washdown and watertight enclosure. It is designed to operate 208-230 Volt 3-phase AC induction motors through 3.6 Amps RMS. The sine wave coded Pulse Width Modulated (PWM) output operates at a frequency of 16kHz which provides high motor torque, high efficiency and low noise. Due to its user friendly design,the KBAC-24D is easy to install and operate. Tailoring to specific applications is accomplished via selectable jumpers and trimpot adjustments, which eliminate the computer-like programming required on other drives. However, for most applications no adjustments are necessary. Main features include adjustable RMS Current Limit with I2t Motor Overload Protection. In addition, adjustable Slip Compensation provides excellent load regulation over a wide speed range. Power Start delivers over 200% motor torque to ensure startup of high frictional loads. Electronic Inrush Current Limit (EICL ?) eliminates harmful AC line inrush current and adjustable Linear Acceleration and Deceleration make the drive suitable for soft-start applications. The Ride Through feature provides a smooth recovery to the previous set speed during a momentary power loss and Regeneration Protection eliminates tripping due to rapid deceleration of high inertial loads. Standard front panel features include diagnostic LEDs for Power On and Control Status, a Start/Stop Switch and a Main Speed Potentiometer. Other features include a Barrier Terminal Block to facilitate wiring of the AC line and motor, adjustable trimpots (MAX, MIN, ACCEL, DECEL, COMP, CL, BOOST) and customer selectable jumpers (line voltage,motor horsepower, auto or manual restart modes, motor frequency, frequency multiplier, fixed or adjustable boost). Optional accessories include a Forward-Stop-Reverse Switch, Auto/Manual Switch, Power On/Off Switch, Signal Isolator /Run Relay and a Multi Speed Board. Quick-connect terminals are provided for easy installation of all accessories.


----------



## Karl_T (Nov 5, 2020)

At least for me, not having a brake resistor is a deal breaker.  I am too used to having the machine stop when i tell it and not coast down over a few to several seconds. For one, it would make threading to a shoulder almost impossible. others may say this is no big deal.  Do not consider my word gospel, just my opinion.

i for sure see the appeal of something that just plugs in.


----------



## Seth (Nov 5, 2020)

Fair enough. I do appreciate your opinion. I’ll continue searching to see if I can find the best combination of simplicity and functionality.

Thanks again.



Karl_T said:


> At least for me, not having a brake resistor is a deal breaker.  I am too used to having the machine stop when i tell it and not coast down over a few to several seconds. For one, it would make threading to a shoulder almost impossible. others may say this is no big deal.  Do not consider my word gospel, just my opinion.
> 
> i for sure see the appeal of something that just plugs in.


----------



## Seth (Nov 6, 2020)

Karl,
id like you opinion on the Teco L-510 1 Hp.  Also, can I safely run a break resistor with a screw on Chuck?


----------



## Karl_T (Nov 6, 2020)

Looks like a nice enough VFD but I have not used that particular brand.

I will defer to others about the screw on chuck. But yep, maybe that's a problem.

<EDIT> test if they have customer service.  Text on the chat line for the size of the pot for remote speed control. Its likely 10K ohm but may be 5 or even 2.


----------



## mksj (Nov 6, 2020)

I installed two KB drives on my previous mill for axis drives and helped a few other people that had purchased them for mills and lathes. They are good as a stand alone unit where you basically turn them on/off and adjust the speed from the control panel, but beyond that they are less ideal in machines where you want remote operation controls and more flexibility/control on how the VFD operates. Most of the models have no programing, so adjustments are made with pots and jumpers on the control board. The KB drives have very minimal braking and speed control/power was an issue at lower speeds, I ended up replacing it with a Hitachi WJ200. On the plus side they are often used for grinders because they are sealed and basically you want an on/off button and speed control. Depending on the model, they may require additional components for remote operation and it all adds up. On the model you indicated it does have the option for a for/rev switch but it does not have traditional terminals for an external switch.

Teco L-510 are decent and a good basic VFD with a warranty and support. They are not sealed but can be placed in a cabinet or use a shield to prevent swarf getting into the unit. The L-510 does not support an external braking resistor, but has an internal one which can provide some braking. To aggressive braking with a screw on chuck can be dangerous, so I would stay in the 3 second range and maybe a bit longer if higher speed unless you add a chuck lock.The Teco E-510 is a more full featured model that does support an external braking resistor and has more programmable inputs. The do make a sealed E-510 unit but adds about another $100. I find the Teco's to be a bit easier for people to  program and use, and tend to be very good VFD's at the price point and features. These are sensorless vector drives so they will give a bit more consistent low speed operation,  although with the stock motor I would limit the low speed to around 20-30 Hz due to cooling and decreasing Hp.









						VFD, 1hp, 230V, 3 Phase, IP20, Medium Duty, Speed
					

VFD, 1hp, 230V, 3 Phase, IP20, Medium Duty, Speed Potentiometer, Easy to Program, Compact, 150% Overload, V/F Control, Auto-Torque Boost or Sensorless Vector, 3 Phase Output




					www.wolfautomation.com
				











						VFD, 1hp, 4.5A CT/VT, 230VAC, Single and 3 Phase,
					

VFD, 1hp, 4.5A CT/VT, 230VAC, Single and 3 Phase, F1, 6.46x3.57x5.96", Med. Duty Compact, NEMA1/IP20




					www.wolfautomation.com
				











						VFD, 1hp, 230V, Single Phase, NEMA 4/IP66.Indoor/M
					

VFD, 1hp, 230V, Single Phase, NEMA 4/IP66.Indoor/Med Duty, W/ Keypad, Dscnct & Pot on Cover




					www.wolfautomation.com


----------



## Karl_T (Nov 6, 2020)

FWIW, mksj is the resident VFD guru. Do what he says. he must be sleeping at the switch. Normally expect expect him to chime in on VFD queries right away


----------



## Seth (Nov 6, 2020)

Thank you gentlemen.  I ordered L510-201-H1-U.


----------



## Seth (Nov 12, 2020)

And in an interesting turn of,events, the electrician came out yesterday to add a dozen new outlets to the shop and lo and behold, my existing 220v outlet is using 2 legs of 3 phase power.  All for naught.

lathe will work today!


----------



## Weldingrod1 (Nov 12, 2020)

Omg! That is some luck!

Sent from my SM-G892A using Tapatalk


----------



## Seth (Nov 12, 2020)

Weldingrod1 said:


> Omg! That is some luck!
> 
> Sent from my SM-G892A using Tapatalk



yeah!  When I moved into the shop I was renting and never really paid any attention.   I bought the shop in October and suddenly I cared.   lathe works perfect


----------



## Seth (Nov 17, 2020)

View attachment trim.93F6B8FF-A566-4CE9-8351-96354FD026B6.MOV


----------

