Suggestions on my vfd conversion

YYCHM

(Craig)
Premium Member
Well I'm wiring up remote switches on the machines right now and will likely post a picture "schematic" for others to check so I can avoid smoke when I put power to it. But I am also waiting for my motors to come which won't be to late next week.

Where did you source the motors from and how much were they?
 

DPittman

Ultra Member
Premium Member
I learned something the hard way about hall effect sensors today. It matters which side of the magnet is facing the pick-up head/sensor.

I first put one on the drill press and tried it, great, no problems right of the bat, then did same on milling machine. Nothing but zeros on readout, maybe it's the readout...tried a different one, no different.

Maybe it's the tiny connector plug, fiddled with that and examined it, no it appears ok.

Well I guess it must be my soldered connections, so I unraveled and redid some of them, still nothing.

It must be the sensor head itself, dang it. Better check on line for possible causes....yup someone suggested trying to flip the magnet end for end. Yup that's all it was.
 

DPittman

Ultra Member
Premium Member
Same emotors as yours and a "Hallmark" brand from Amazon. Both 1.5hp but the emotorsdirect.ca motor is cast iron frame and higher service factor than the rolled cage motor from Amazon.
I just got my emotorsdirect.ca order, the motor looks good visually but one thing that surprised me was the date on the name plate is 2007! This thing has been sitting on a shelf for 14 years! Shouldn't matter a lick tho. Did you happen to notice the date on your motor @David_R8 ?
 

DavidR8

Scrap maker
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If I recall correctly mine had a similar date. I don’t know if it was the same but I remember thinking that it was sitting for a while.
 

DPittman

Ultra Member
Premium Member
Had a bit of rain today so couldn't work in the fields so it was an opportunity to do some shop work!
My new 3ph motor for the mill has a .875" shaft and the old one was .750. So I had to bore out the cast iron pulley which bored beautifully and then that left me with the keyway that now needed to be deeper.

I made a broaching attachment for my lathe a while back and thought that would be the perfect application for it. However I soon remembered that it only has a slotting/broaching travel of less than 2". Oops. The pulley with the hub needs 2.75" keyway.
So I eneded up using a 3/8" boring bar with a 3/16" piece of hss in it and held in the tool post. I took a zillion cuts as it had tremendous flex and I realistically was only taking about 1 or 2 thou off with each swipe. Good thing it was easy machining cast iron. It turned out surprising well.
20210505_130235.jpg 20210505_130602.jpg 20210505_123745.jpg
Now to figure out motor wiring diagrams. 20210505_113008.jpg
 

DPittman

Ultra Member
Premium Member
So I powered up my vfd's for the first time. No motors hooked up yet just power to them. I notice when I kill the power to them the vfds continue to run for a bit. Is this normal? I have two vfds powered on the same line and one of the vfd runs on a bit longer than the other when I kill the power?
 

Darren

Ultra Member
Premium Member
So I powered up my vfd's for the first time. No motors hooked up yet just power to them. I notice when I kill the power to them the vfds continue to run for a bit. Is this normal? I have two vfds powered on the same line and one of the vfd runs on a bit longer than the other when I kill the power?

Completely normal
 

YYCHM

(Craig)
Premium Member
So I powered up my vfd's for the first time. No motors hooked up yet just power to them. I notice when I kill the power to them the vfds continue to run for a bit. Is this normal? I have two vfds powered on the same line and one of the vfd runs on a bit longer than the other when I kill the power?

Yup, normal. They have a very large capacitor in them.
 

DPittman

Ultra Member
Premium Member
Thanks. I guess that would be a good thing to remember when I'm hooking up the motors to them eh. Potential shocking hazard?
 

YYCHM

(Craig)
Premium Member
Thanks. I guess that would be a good thing to remember when I'm hooking up the motors to them eh. Potential shocking hazard?

Oh Ya! Will give you a good jolt if you're not careful. I was mucking around with one too soon after killing the input power and got zapped pretty good:rolleyes:
 

Darren

Ultra Member
Premium Member
Be very careful, the DC bus can have upwards of 400 volts for several minutes after the power is cut. A friend of mine was recently electrocuted, fatally, by woodburning with a microwave transformer. Guess its a new thing. Be careful
 
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DavidR8

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Yikes Darren, that's scary as heck. Good warning, I'm sorry for the loss the loss of your friend.
 

DPittman

Ultra Member
Premium Member
Be very care, the DC bus can have upwards of 400 volts for several minutes after the power is cut. A friend of mine was recently electrocuted, fatally, by woodburning with a microwave transformer. Guess its a new thing. Be careful
Egads! So by leaving them unpowered for 5 minutes will that GAURANTEE that they are safe?
 
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