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Roto phase

I set up my lathe a little over 30 years ago with the help of some knowledgable friends.. As I live in the country we also used a 5hp roto phase... It started complaining this morning with some terrible noises.. Only thing on it is my lathe with its 3hp motor..

So what is going to be my best bet going forward..?

Any help would sure be appreciated !
 
Or, get a new VFD. For my 2HP lathe I got a Hitachi and it was only about $270. Don’t remember the model #.
 
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Are the Hitachi's difficult to hook up? Do you continue to use the lathe controls for spindle speed ?

It's possible Walt, I haven't pulled it out yet. Darn thing weighs abut 200lbs...
 
Are the Hitachi's difficult to hook up? Do you continue to use the lathe controls for spindle speed ?
I didn’t have any trouble. There are about a million settings available, 99.9% of them you probably wouldn’t need. You still use the lathe controls for spindle speed (in gross increments) as labeled on the lathe. That’s with the frequency set at 60Hz. I added a potentiometer mounted on the plate next to the jog button for adjustment from 30Hz to 80Hz which would be 50% to 120% of what is set by the lathe controls. I also set the jog button for 6Hz. I could (should) have added a switch so I could jog in reverse as well.
 
Does the roto phase sound like it is running up to speed? If it comes up to speed might just be a bearing or debris if it doesn’t come to speed or humms, buzzes or vibrates could be a bad capacitor. Could be more serious but IME they are pretty bulletproof Now that I said that mine will dump next week ;)
 
Thank you for that diagnosis but I know less than zilch about the internals of this.. Could you elaborate a little ??
Paperpuncher gave you good advice, These are not that complicated. Capacitors are used to start the motor momentarily and then cut out, It runs on 2 legs of 120 so, 240 single phase power, As it turns it is generating power that can be tapped from the motor to give you L1 L2 and L3 creating 3 phase power for your needs.

A potential relay is used to cutoff power to the capacitors.

There isn't a lot of things to go wrong, You can unhook each capacitor and check them with an old analog style multimeter.

My guess is a capacitor or bearings, Based on noise. But without being there it's hard to say.

The bearings should be checked.

You can check everything on this phase converter.

I would start at the panel and make sure you are still getting power on both legs of your circuit breaker.

A 2 pole breaker can go bad on one side which would give you 120 to the ph conv causing noise also.

I still use a 5hp "Roto-Phase" Brand converter from the 70's or 80's and it powers my 3 hp Turn-Pro lathe perfectly.

Edit to add:

Capacitors can kill you so make sure you don't touch the terminals. I bought some bleed down resistors and epoxyed one to a screw driver to reach in and bleed them down. Just be careful.
 
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So Elr was being indifferent ---- and itchy giving more clues, lol...

Sniper, Thanks you for taking time to provide a good checklist.. I've listened to this thing for thousands of hours, it's definitely got a problem.. I'll start checking
 
There are start capacitors which will burn up after having current to them for more than a few seconds, Which is why you need the potential relay to disconnect the power after startup, Then there are run capacitors which are oil filled and are used continuously.

Each capacitor has numbers that you have to go by. Make sure you put the same number capacitors back in as phase converters are balanced. The same thing if the relay is bad, There are a myriad of different relays too, Get the same one if you can. There is a place in Fremont Calif that sells most of the parts, I can't remember the name, The guy is kind of cranky sometimes on the phone. But he knows what he is doing and you won't find the parts any cheaper, At least that's the way it was years ago when I was repairing a few of these things and other motors.

I looked it up, The name of the place is Temco, Looks like he may have been bought out by someone in Texas now. He was in Fremont Ca.

 
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If you need caps or a relay any hvac distributor will most likely have what you need on the shelf. Caps for sure, relays might be hit or miss. And today’s quality is crap compared to yesterdays. Like many things today all the hvac start components quality has dropped over the last 10 years or so and that’s just the way it is.
 

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