# VFD Help Needed



## vocatexas (Oct 7, 2021)

I bought a VFD to run my South Bend lathe. It's got a 2 1/2 horsepower motor and I got to thinking that firing up a 40 hp RPC was just silly to run that small a motor. I ordered this VFD: https://www.ebay.com/itm/1414410659...,osub=osub,crd=crd,segname=segname,chnl=mkcid

Wow, what a link...

Anyway, I got the 220 circuit run to the lathe location yesterday. My electrician nephew wired the VFD to the lathe when he was here a couple of weeks ago, and I had him put a welder plug on the in-put side of the VFD so that if I ever wanted to move the lathe it wouldn't have to be un-wired and re-wired. I finally got the courage up to try powering it up today. It gives an error code that, according to the manual means it's receiving too much current. When I probe the wall outlet, my meter shows 244 volts. The VFD fan powers up for about two seconds, then stops and the display begins flashing.

Any ideas what I've done wrong here?


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## rabler (Oct 7, 2021)

First off, is the VFD wired directly to the motor, or did you essentially plug the lathe into the VFD?
VFD’s are designed to have nothing between them and the motor.  No switches, contactors, etc.  It is possible that wired to an open switch, the vfd would report too much current as an erroneous message.

Second possible issue, you say it is a 2.5 hp motor.  You have a 2hp vfd.  It may see the starting current to that motor as too much.  A vfd can be rated bigger than the motor, at least by a factor of two, but not smaller.  (Actually it is the amperage rating, but hp follows amperage fairly closely).  So you need a 3hp or 5 hp rated vfd.

The 220V vs 244V should be not be a problem.


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## vocatexas (Oct 7, 2021)

I'm sorry, I did say 2 1/2, it's actually 2 horsepower. There IS a drum switch on the lathe, but I have it in the 'forward' position and I took the handle off so it won't be moved. Long story, but that's the way I have it. Would simply having a closed switch cause a problem? I could understand if it was open. The lathe WAS running when I bought it. We simply disconnected it from a junction box and left all the remaining wiring alone.

I have another VFD set up the same way. That one is a 5 hp unit. Would it hurt to hook that one up to the lathe and try starting with it? I was under the impression that you wanted to size a VFD very close to the size of the motor it was going to run.


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## Ulma Doctor (Oct 7, 2021)

i'll bet if you were to go through the settings on the first vfd, 
you would find the cause of the overcurrent error


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## jwmelvin (Oct 7, 2021)

Can you be more precise about the error? “Receiving too much current” doesn’t make sense. The VFD receives a voltage and may draw current from the wall. The motor draws current from the VFD.


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## markba633csi (Oct 8, 2021)

Usually one would size the vfd a bit larger than the motor for example for a 2 hp motor you would want a 2.5 hp or larger vfd rating.
Having any switch in between the vfd and the motor is asking for trouble- if the switch gets bumped or one of the contacts decides to go slightly open circuit it can blow the vfd output stage- bad news since these things are not easily repairable
If you need to have the ability to reverse the motor you should do it at the vfd not by switching the motor leads
-Mark


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## rabler (Oct 8, 2021)

Many people have had the inexpensive off brand VFDs work fine, but often with them it does pay to heed @markba633csi's advice and oversize them.  Not as much of an issue with name brand VFDs, but obviously you pay more for them.   Hitachi and Teco seem to be common name choices.


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## Dabbler (Oct 8, 2021)

There is more to installing the VFD than the physical wiring - Just in case you didn't correctly set up the VFD parameters.  You didn't mention programming it, so in general, you need to set the current of the motor and one or two other parameters:  I programmed all of my VFDs 5-6 years ago so I can't remember the others off-hand.. (I can check if you like)

The very most important setting is the motor current at 60Hz, found on the motor faceplate.  This should help you avoid overcurrent errors.

Please don't leave the switch in-circuit.  This is a mistake that will likely cause the destruction of one of you VFDs some day.  There is no need to have it there - BUT - it is important to make the lead from the VFD to the motor as short as you can.  The over-simplified explanation is that the VFD senses several parameters in the motor as it is turning, and long leads inductance, extra capacitiance from the leads, resistance from the switch can all play a part in the VFD not doing its 'best job'.

For cheaper VFDs and for lathes, it is really important to buy a much larger capacity VFD For it - at least 30% bigger, but 2X wouldn't hurt. (OK, perhaps the wallet)

I also have a RPC for my big lathe as buying a 15HP VFD for it would be a little pricey


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## Dabbler (Oct 8, 2021)

A quick followup to the previous post:  They say in the ad that it is for light-duty motors, and not for heavy duty motors.  This may mean that the motor inrush current of  the motor trying to overcome the inertia of the gears and chuck is  too much for your inexpensive VFD.

If you move your 5HP VFD to your 2HP motor to test this,  be sure to revise your motor current value.


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## Ulma Doctor (Oct 8, 2021)

I have not experienced any complications in using inexpensive vfd’s in 8 years of torture testing on everything from surface grinders to lathes to milling machines to tool grinders
Superstition often prevents trying new things


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## RandyWilson (Oct 8, 2021)

I have a thread here on programming these VFDs.  Unforch, I have to be back to work in like three minutes.  But... if when you power the VFD up it shows 400 like in the ebay pic, that is your problem. You need to program it first. If I remember correctly, it's Pn32 set to 6 puts it in 50 hz mode and the lathe should power up. We can fine tune from there.


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## RandyWilson (Oct 8, 2021)

Tuning the Isacon HY series VFD
					

Since I have decided to banish all bad-magic phase twisting devices and only use good-magic, I figure it's time to really learn to tune these Huanyang VFD's. I have two identical ones, HY02D223B, purchased nearly a year apart. I have Googled extensively, but found no helpful information on these...




					www.hobby-machinist.com
				





Here is the thread


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## vocatexas (Oct 8, 2021)

Randy, thanks for the reply. And thanks to everyone else who has made suggestions. I'm kind of in over my head. I'm fairly good with mechanical equipment but AC electrical just doesn't compute with me. Also, I was under the impression that if all I was going to use the VFD for was to get 3 phase power and not use any of the other features it didn't need programming. Color me stupid...

I went back out into the shop today to try to get this thing going again. I did watch a YT video that helped a small amount. I tried resetting some of the parameters, but couldn't get the menu to come up. I removed the small control panel and found a bent pin inside. After straightening it and reinstalling the panel, I could access the menu. Going with the information in the video, I reset several of the menu items. On Pn 01, I have no idea. What is a 'runtime frequency'? On Pn 02, I reset from 400 to 60. Pn 08 and Pn 09 are acceleration and deceleration times and I reset them to 5, just as a starting point. The video suggested resetting Pn 10,11, and 12 which are maximum output frequency, maximum runtime frequency, and motor rating frequency. All of these I set to 60. I _think_ all these saved. I still get no response from the motor. VFD powers up and fan comes on for a couple of seconds, then the fan quits. Display sits there blinking '60'. I did check the internal fuse, and it is fine.

In my initial post I had said I got an over-voltage code. I misread the code; it was an UNDER-voltage. That code would pop up after I unplugged the VFD but before the display went dark. I'm pretty sure it was just telling me it wasn't getting any current because it had been unplugged.


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## MikeInOr (Oct 8, 2021)

Slack or remove the belt from the lathe motor and see if it will start without trying to push any load of the lathe.

On one of my radial arm saws the VFD would always trip when I was pushing the saw through a cut (I use that RAS to cut metal with an abrasive blade).  I found the trip current setting in the VFD and increased the value which solved all my problems.  ...that was about 10 years ago so I don't remember the exact name of the parameter.


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## vocatexas (Oct 9, 2021)

The belt is slack and I've got the geartrain in neutral so there shouldn't be any load on the motor. I'll open the base up tomorrow and confirm by hand.


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## MikeInOr (Oct 9, 2021)

Looking through the thread that RandyWilson linked to above and the *manual he linked to in that thread* these 5 parameters look important and are ones that I would suggest you look at to make sure they match the tag on the motor.

PD141 Rated Motor Voltage - Set according to Motor nameplate
PD142 Rated Motor Current - Set according to Motor nameplate
PD143 Motor pole number - 02—10
PD144 Rated Motor Revolution per minute - 00—9999
PD176 Inverter Frequency Standard - 0：50Hz 1：60Hz (Should be 1 - 60Hz here in the US)

These also caught my eye:
PD118 Over-voltage Stall Prevention - 0：Invalid 1：Valid
PD119 Stall Prevention Level at Accel. - 0~200%
But I would not mess with them until the above 5 parameters are set correctly and tested.

Last thing I would do if none of the above get your motor started is set this parameter to (maybe) 10seconds which should lower the starting current because the motor is accelerating slower:
PD014 Accel. Time 1 - 0.1~6500.0S (default 5sec)

When you buy a 3hp rated VFD the initial values for the first 5 parameters are usually defaulted to a typical 3hp motor.  So if you run a 2hp motor on a 3hp VFD you usually don't have to mess with these parameters because the defaults are higher than what is needed for a 2hp motor.  Since you have a 2hp motor on a 2hp VFD it is more important to set these parameters properly to prevent the problem you are experiencing.  They should also be set properly for a 2hp motor on a 3hp VFD too!!!  ...but the problem you are experiencing should not arise if they are not.  Setting these parameters properly on a 3hp VFD controlling a 2hp motor will do a much better job of protecting the 2hp motor from an over current situation that might harm the motor.


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## mksj (Oct 9, 2021)

In addition to the parameters you might post a picture of the wiring to the terminals. Often when there is an under voltage error it is because the neutral was wired in or the wrong terminals for the input power, but in this case I think it appears as the capacitors drain voltage once unplugged.

Many of these generic  VFD's  are sold for high speed spindle motors, not standard 2 or 4 pole motors, almost all VFD's need some programming to work properly. My experience with helping others with these generic VFD's is less than stellar, depends on the application and load. They have a high initial failure rate, but once working seem to do ok. I have more issues with lack of programming flexibility, terrible manuals, and just plain performance relative to other VFD's I commonly use. Some of the bigger VFD distributors provide tech. support in helping you setting them up.


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## MikeInOr (Oct 9, 2021)

Does this match the manual that came with your VFD?
http://www.jinlantrade.com/ebay/invertermanual.pdf

If so it looks like the parameters I listed above are correct for this VFD.


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## RandyWilson (Oct 9, 2021)

Before things get crazy here, we need to ID which unit you have. My thread is on the Isacon / Askpower units.  Look at your manual. If your parameter setting are in the range of ph01-ph36 then you have an Isacon and we can go forward. If the parameters go to ph1xx (three digits), then it's a a HuangYang and my thread does not apply.

The parameters you listed are for the Isacon series. so my thread will apply and we are going to move forward. Step 1 is to step away from Youtube. Youtube is for stupid cat videos.  Even This Old Tony had to resort to including cats in his videos in order to get his ratings out of the gutter.  Remember, random faceless postings on some text message board are much more reliable than some narcissistic self proclaimed expert on youtube.

This is fact.

What happened when you programmed those settings is you told the VFD to go from the base frequency (default is 11) and ramp up to 60hz over 5 seconds, without ever going over 60hz, or under 60hz.  Of course the VFD came up, gave you a really confused look for 5 seconds, and shut back down.

These VFDs come out of the box with a default set to drive a high speed CNC spindle. 400hz starting point. South Bends don't like that. Pretty much every parameter is wrong. The later Isacon units have a second default table, 50hz.  While not a final setting, this gets you much closer to what you need. So set that first.

  Pn32=6

This will reset everything back to factory defaults, but using the 50hz table. This will remove all of the changes you did.

  Now, set a reasonable starting freq.

Pn02=20

And to make sure that you have panel control.

Pn03=2
Pn04=1

Now hit start. The lathe should start up at a slowish speed. The arrow keys will allow you to increase the speed.. You can do a bit at marveling.  Later today I will write down all of the settings I use on my 14 1/2 South Bend.

BTW, you *will* be using the VFD for start, stop, and speed control, so mount it in a good reachable place. I haven't changed the belt settings on my lathe in years. The VFD and backgear gets me everything I need.


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## vocatexas (Oct 9, 2021)

The manual Mike linked above looks nothing like the manual I have.

Somewhere during all this I'm pretty sure I ran across the mention that these were either Isacon or a clone of Isacon. In my manual the parameters are listed as Pn, not PH, and run from 1 to 35. Pn 35=6 is initialization for 50 hz values. I've got to do some PM on a couple of pieces of equipment this morning. When I get done I'll try the settings you suggest and post back. 

Thanks for the help, fellas!


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## RandyWilson (Oct 9, 2021)

The manual I have here on my desk says "Ph".   The VFD itself says "Pn".  I will edit.


Edit:

 I have four of these things now, Three in constant service, one as a back up. Of these, I can put my hands on three manuals. The oldest, the one here at the desk, says "Ph". The others are indeed Pn. But all three show Pn32 as being the parameter lock and reset register, with Pn35 being production date.  If yours is different, then life just got even more complicated.

 Can you compare your list to the one here https://www.hobby-machinist.com/threads/tuning-the-isacon-hy-series-vfd.59364/post-489160  ?


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## vocatexas (Oct 9, 2021)

Okay, I reset to the default 50 hz (Pn 32=6). I hit run, then the motor kind of rattled for a couple of seconds. I did this three times. First two times I got the code for 'acceleration overcurrency'. The last time I got the code for 'steady state overcurrency'. I'm not running yet, but the motor made noise. I call that progress!


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## RandyWilson (Oct 9, 2021)

That...... is not promising.  As others have said in the beginning, you did undersize the unit. I'm running the next bigger 2.2Kw unit.  Let's try the settings I use on mine and see if we can nurse it to run. Mine is a 14 1/2 South Bend, but doesn't have the original motor.

Pn01 Default display 60 (so it displays hz rather than rpm)
Pn02 Initial startup frequency 20
Pn03 Source of runtime freq 2 (panel)
Pn04 Source of runtime command 1 (panel)
Pn05 Rotation Direction 3 both
Pn06 Stop method 2 braking
Pn07 Start by external signal 1 disable
Pn08 Accel time 8 seconds
Pn09 Decel time 6 seconds
Pn10 Max runtime freq 90hz
Pn11 Min runtime freq 10hz
Pn12 Motor rating freq 60hz

And the rest at default. What these settings will do is have it start at 10Hz, and ramp up to the set speed at a rate of 10hz per second. It may error on the decel times, but we'll worry about that IF we can get it to ramp up. The bit of good news is you will always be ramping in the lathe with no load. Cutting load is applied after the speed is stabilized. Not so with things like an air compressor. That took a bit more tuning, but it too is running fine, albeit on a much large unit.

If she doesn't spin up with this, then it looks like we'll be needing a bigger unit.


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## vocatexas (Oct 10, 2021)

Thanks, Randy. So, VFDs need to be oversized like RPCs? I asked in another thread here before I bought mine and was told 'no'. Oh, well...live and learn. Good thing is these are relatively cheap.

I'll be heading over to the shop in a bit. I'll give those settings a try and post back results.


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## RandyWilson (Oct 10, 2021)

Oversized may not be the correct word. The HP ratings on these things are suspect, just as the horsepower ratings on modern motors are much more optimistic than days of old. The 1 and 1.5 HP motors on these old South Bends have a lot more grunt and use more electricity than the 3hp motors of today. They musta had bigger horses back then.

Right now we're fighting the in-rush of trying to spin the motor straight to a reasonable speed. In reality the VFD should have enough reserve to do that. But since you have this one, so let's see how it does with a reasonable ramp-in.


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## Ulma Doctor (Oct 10, 2021)

on 2 lathes i have a 2hp VFd with a 2hp motor, and a 3hp motor with a 3hp vfd-
both are inexpensive VFD's both running on single phase power.
where it may be a good idea to oversize, i have not and have had no issues on either machine

i would suspect we have a parameter out of range somewhere


i use .2 accel
coasting for braking
minimum 20Hz


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## RandyWilson (Oct 10, 2021)

Mike, the question isn't so much the HP rating, as the current rating. Are yours 1.5 or 2.2kW?  Both my mill and lathe have motors rated at 1.5HP or less. And I'm a cheap SOB; not known for overbuying. So how did I end up with 2.2kw on both? Likewise I have a 7.5kW VFD on the 5hp compressor. EBay ads now claim the 7.5 is 10HP. I am suspecting that the advertised HP rating has changed.


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## vocatexas (Oct 10, 2021)

I've changed all the parameters to your suggested values. I can't get Pn 02 to stay set to 20. I set it, go back to check, and it's back at 60 again. All other settings seem to be taking. I got my wife to come out and hit the 'Run' button while I watched inside the contactor box behind the lathe. The rattle I hear is the contactor.

I've got two more VFDs I haven't hooked up yet. They are rated at 5 hp. Should I try connecting one of them to this lathe and see if that makes a difference? Like I said early on, I am NOT an electrician. If I wire one of these in, does it matter the order the three hot out-put wires are in, other than motor rotation direction?


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## mksj (Oct 10, 2021)

Leave Pn02 to the default value. The VFD needs to be directly wired to the motor, it cannot be hooked up to the plug or power the controls. If your contactors are rattling, it sounds like you are trying to run them off the VFD. NO contactors are wired into the circuit, the VFD connect to the motor, you use the low voltage inputs through a separate switch which is completely separate from all the other electrics. You do not necessarily need to oversize a VFD if the rated output AMPS is sufficient to drive the motor AMPS in the operating mode ND, HD you need.. I like to have at least a 10-20% margin, but it should work.


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## Ulma Doctor (Oct 10, 2021)

RandyWilson said:


> Mike, the question isn't so much the HP rating, as the current rating. Are yours 1.5 or 2.2kW?  Both my mill and lathe have motors rated at 1.5HP or less. And I'm a cheap SOB; not known for overbuying. So how did I end up with 2.2kw on both? Likewise I have a 7.5kW VFD on the 5hp compressor. EBay ads now claim the 7.5 is 10HP. I am suspecting that the advertised HP rating has changed.


i have a 1.5KW inverter on the 2hp motor and a 2.2Kw inverter on the 3hp motor- both are using single phase to produce 3 phase
conventional wisdom would normally oversize the inverters to 2.2Kw and 3Kw respectively
i can only speculate as to how you ended with 2.2Kw inverters on both of your machines


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## RandyWilson (Oct 10, 2021)

This!!!   No contactor, or any other switching device between the VFD and the motor.


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## vocatexas (Oct 10, 2021)

Ah, okay.

Gotta run into town with the wife unit for a while. When I get back I'll see about rewiring directly to the motor. I don't think I'd ever heard that said before. I just figured the contactor still needed to be there, but, if I'm beginning to wrap my head around this, the VFD not only provides the 3 phase power, it also takes the place of the contactor. If you are running a RPC you would still need the contactor, though. Correct?


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## mksj (Oct 10, 2021)

Correct, RPC is a 3 phase power source for the machine. VFD is a power source for the motor, it does not provide sine wave output it is PWM (little pulses which mimic a sine wave) so cannot be used to power electronics, transformers etc. An RPC uses the single phase input and generates a 3rd phase (wild or generated leg), the generated leg should not be used to provide power to the transformer, etc. There is some types of VFD's Phase Perfect which generates the just the third leg and they filter it heavily so it essentially looks like a sine wave. It can be used as a power source for the machine, they are also very expensive.


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## RandyWilson (Oct 10, 2021)

The VFD is everything.  3 phase supply, contactor, control switch, direction, speed.... it has to have the final say in everything.  These things work by taking line current, untwisting it back to DC, then chopping it back up and shoving it down the three wires. To do this, it must have a small amount of electron storage, a buffer, that it fills based on predicted need.  A sudden open circuit from a contactor or switch will lead to a sudden oversupply, often followed by bad smells.  And smoke.


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## vocatexas (Oct 10, 2021)

Thanks for the explanation, guys. That helps.


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## vocatexas (Oct 10, 2021)

I rewired the VFD. I took the three hot wires running into the lathe from the VFD and tied them directly to the three wires running to the motor after disconnecting them from the contactor. I can hear the motor 'bump', so I think the windings are energizing, but then I get the 'acceleration overcurrency' message again. Is it time to try hooking up one of the 4 kw boxes or have I missed something here again?


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## RandyWilson (Oct 10, 2021)

It's a reasonable test. This 1.5kW unit has seen some duress.


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## vocatexas (Oct 10, 2021)

(Gene Wilder from Young Frankenstein) IT'S ALIVE!

Thanks so much for all the patience and help. I wired one of the 4 kw VFDs in and set all the parameters as you had instructed. I hit the 'run' button and the motor began to turn. I ran the lathe through a few paces to make sure all was good and re-started it a few times. The motor has a high-pitch whine, but after running about ten minutes the motor is still quite cool to the touch. If all goes as planned, I'll make my first chips in the new shop tomorrow. I've got a paying job waiting for the South Bend.

Given my experiences here, do you think I should go ahead and order a larger VFD for my 5 hp motors, or do you think I simply blew this one out by leaving the contactor in the circuit?

Many, many thanks again!


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## Ulma Doctor (Oct 10, 2021)

the whine is the carrier frequency
by increasing this setting to between 10KHz and 14KHz you'll find a reasonable frequency to the ear.
very high carrier frequencies are not great for all motors


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## RandyWilson (Oct 10, 2021)

There are fuses inside on Line in. Slim chance, but maybe one of those is popped. You have to strip the box down to the power board, third layer in.


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## vocatexas (Oct 11, 2021)

I want to thank everybody for all the help. I now have a much better understanding of how these units work. And, today I made the first chips in my new shop with my South Bend. I've got quite a back-log of projects on the list, but the next machine project should be getting my 16 inch L&S up and running. It will be using a VFD as well. Hopefully all I've learned here will make that a much less frustrating experience.


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