Understanding vendor warning: phase converter

A VFD is an entirely different thing from a static converter. A VFD actually generates true three-phase power. A "static converter" is a network of capacitors and relays that converts a three-phase motor into a capacitor-start capacitor-run single-phase motor. It does not, in and of itself, produce three-phase power (though it can be a component of a rotary converter). If you treat a static converter as a black box that takes single-phase power in one side and puts three-phase power out the other you will get into trouble.

BTW jogging is very hard on motors and controls.

Hence my comment. I burned up two starter capacitors before I twigged to the idea that I was the problem using the jog button while threading.
Live and learn!

jim
 
Hence my comment. I burned up two starter capacitors before I twigged to the idea that I was the problem using the jog button while threading.
Live and learn!

jim

Switch to a three phase motor and a VFD and you can jog to your heart's content. The jog speed should be adjustable on the VFD.
 
Switch to a three phase motor and a VFD and you can jog to your heart's content. The jog speed should be adjustable on the VFD.

Yes, and if anyone knows how to read the hieroglyphics of the HuangYang VFD regarding the jog function, please let me know. I keep meaning to vow to decipher the manual but, I get a headache just thinking about it.

Ray
 
Yes, and if anyone knows how to read the hieroglyphics of the HuangYang VFD regarding the jog function, please let me know. I keep meaning to vow to decipher the manual but, I get a headache just thinking about it.

Ray
What do you want to know?
 
What do you want to know?

It's mainly laziness on my part but, I never connected the jog button when I converted my PM1236 to 3 phase. All other switches and safeties work fine. As I recall, I made jog connections but could not get it to jog in forward or reverse but rather, forward jog only. I diddled with it for a short while and deemed it unimportant but, one of these days, I'd like to get it working properly.

Ray
 
Thanks, I get the drift that on some lathes do not trick them when they need 3 phase. I did not get the vendor name, but the machine looked Chinese without a branding name plate. So this subject should give pause before buying a lathe advertised 3 phase ,while the buyer has only single phase houshold service? (I read the Wiki writeup on phase converters -3 types).
 
Thanks, I get the drift that on some lathes do not trick them when they need 3 phase. I did not get the vendor name, but the machine looked Chinese without a branding name plate. So this subject should give pause before buying a lathe advertised 3 phase ,while the buyer has only single phase houshold service? (I read the Wiki writeup on phase converters -3 types).

I'd ask the seller if he used a VFD, Rotary Converter or Static Converter. VFD and Rotary are preferable and less likely to overheat the motor provided they were properly sized and configured.


Ray
 
It's mainly laziness on my part but, I never connected the jog button when I converted my PM1236 to 3 phase. All other switches and safeties work fine. As I recall, I made jog connections but could not get it to jog in forward or reverse but rather, forward jog only. I diddled with it for a short while and deemed it unimportant but, one of these days, I'd like to get it working properly.

Ray
This is my control panel. with the rocker switch pushed in at the top twist the lever switch to the left (ccw) to start and run normally, to the right (cw) the machine runs in reverse. The red button is of course, stop.

Flip the rocker switch down and then the lever switch will jog the machine forward or reverse depending on how you twist the switch, the stop button has no effect.

The speed potentiometer knob can be seen on the left. The photo is deceptive, the machine switch is 2 - 3 inches behind the speed control knob, I keep the knob off and only put it on to switch from 4 to 8 pole (high/low) when the VFD is not supplying power.

Control.jpg

For jogging I set Pd 047 to 07 and Pd 048 to 08. the corresponding terminals are SPM and SPH.

The lever switch is deceptive, it's four switches ganged, two for run (forward and reverse) two for jog (forward and reverse). The rocker switch is DCM for the center terminal and it switches DCM to either the stop button OR to both jog switches.

Pd 020 sets jog acceleration
Pd 021 sets jog deceleration
Pd 042 sets jog frequency (speed)

Edit: I forgot to mention, all the switches are momentary contact except for the rocker switch. Stop is NC, all the others NO.

Control.jpg
 
Last edited:
This is my control panel. with the rocker switch pushed in at the top twist the lever switch to the left (ccw) to start and run normally, to the right (cw) the machine runs in reverse. The red button is of course, stop.

Flip the rocker switch down and then the lever switch will jog the machine forward or reverse depending on how you twist the switch, the stop button has no effect.

The speed potentiometer knob can be seen on the left. The photo is deceptive, the machine switch is 2 - 3 inches behind the speed control knob.

View attachment 73941

I set Pd 047 to 07 and Pd 048 to 08. the corresponding terminals are SPM and SPH.

The lever switch is deceptive, it's four switches ganged, two for run (forward and reverse) two for jog (forward and reverse). The rocker switch is DCM for the center terminal and it switches DCM to either the stop button OR to both jog switches.

Pd 020 sets jog acceleration
Pd 021 sets jog deceleration
Pd 042 sets jog frequency (speed)

Much thanks!


Ray
 
Thanks, I get the drift that on some lathes do not trick them when they need 3 phase. I did not get the vendor name, but the machine looked Chinese without a branding name plate. So this subject should give pause before buying a lathe advertised 3 phase ,while the buyer has only single phase houshold service? (I read the Wiki writeup on phase converters -3 types).

If I was going to spend a few thousand on a machine I'd find a bit more for a VFD. Static converters are for cheapskates like me.
 
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