Clausing 5920 vfd (want to keep clutch)

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sparkplug487

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I got a 5920. It had static converter. Didn't like the idea of that. Ran OK on my 240v but research said a vfd would be better.
Got a Amazon cheap vfd. Said rated for 2hp. After alot of adjusting. I could get it to run the motor. But engaging the church st any sort of high rpm. Would throw a over current fault. I could not program around it. Possibly lack of knowledge on my part. I figured too small of a vfd.
I got a vfd, albeit Chinese, rated for.much larger. 4.4kw. It instantly threw a code. And would not power the motor at all. Gave a phase output fault. No matter what I tried.
 
I am going to finally do what life has taught me.in the past, and buy good quality. Probably a 510. Or whatever you guys recommend.
I spoke with customer service at atc Automation or whatever it is. And he led me to believe I would always have issues with a vfd and a clutch. Is this true? I'd really like to keep the clutch. Can someone point me to a vfd that will for sure work for my 2 hp 3 phase motor. Thanks.

Hopefully I described my problem. Good enough for others to discern what I need.
 
I use a Teco L510 on a Monarch 14x30 with a clutch. 3phase 3HP motor driven by single phase input. Works fine for forward/reverse and variable speed. Clutch lever for clutching and brake, so no need for a VFD braking. Over current startup and over voltage braking is something that can be addressed by setting the right parameters associated with those trips. Basically you tell the VFD to have the motor not change rpms as fast as the vfd program calls for rather than tripping. This is useful on any lathe(regardless of clutch) that may be spinning a heavy workpiece/massive 4-jaw one session and next session a collet chuck with basically no additional load from a tiny workpiece.

@mksj is the vfd guru here and would have best advice if he has time to contribute.
 
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Thanks. I ordered a 2hp teco. The one recommended to me by wolf Automation. I will report back once it shows up. I'm glad to hear I should still be able to use the clutch. Searching this website as best I could without my account validated, I came to the same conclusion you stated. I will need to trick/program the vfd into delaying its reaction.

Possibly a stupid question. I have the 240v circuit on a 30 Amp breaker. I ran 10 gauge from my panel. To a outlet in my shop. And then off that outlet I am going to wire my vfd. Is it OK to gauge down the wire AFTER the vfd, being it should only see a max of maybe 15 amps? Or should a guy just go big the whole way? The larger wire is quite a bit harder to work with. But if it's needed. I can manage. Just curious
 
sparkplug487 said:
Thanks. I ordered a 2hp teco. The one recommended to me by wolf Automation. I will report back once it shows up. I'm glad to hear I should still be able to use the clutch. Searching this website as best I could without my account validated, I came to the same conclusion you stated. I will need to trick/program the vfd into delaying its reaction.

Possibly a stupid question. I have the 240v circuit on a 30 Amp breaker. I ran 10 gauge from my panel. To a outlet in my shop. And then off that outlet I am going to wire my vfd. Is it OK to gauge down the wire AFTER the vfd, being it should only see a max of maybe 15 amps? Or should a guy just go big the whole way? The larger wire is quite a bit harder to work with. But if it's needed. I can manage. Just curious
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So there's a couple factors at play here. I'm weighing in with detail because others may read this down the road.

Wire gauge is constrained by heat buildup which damages insulation, and by voltage loss which deprives the motor of power. These are related in that the power either goes to the motor or heating the wire. Short wires won't really reduce the voltage too much. The biggest overlooked issue inside a machine is to use wire that has good insulation properties. Oil resistance and a high temperature rating because the inside of a machine can get hot.

The trick of most motor loads is even with a VFD that reduces startup load, the peak current briefly can reach 150% of the actual motor rated current. And that peak load is when you definitely don't want the motor being deprived. 14ga wire has a resistance of 2.5 ohms per 1000ft. At that peak a 5 ft section would be a voltage drop of still less than 1/2 a volt over 5 feet piece of wire (a guess of VFD to motor length). That's well within reason. If you needed a longer run than a few feet, 12 ga would be a better choice.

Machine tool hookup wire (MTW) is a good selection,I believe 90 degree C rated. MTW is usually constructed with finer stranded copper wire, so it flexes fairly easy for it's size. Using a 90 degree MTW wire, going to 12 ga would be quite safe. Going to 14 ga would probably be OK. All that said, the Teco manual (or any quality VFD) has some wiring guidelines that should be reviewed.
 
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Specification for 3 phase motor cable after the VFD is 14G, which is what I use for both 2 and 3 Hp 230VAC 3 phase motors. A VFD can output ~150% (~11A for this model VFD) of rated current for up to a minute, all well within the rating of 14G wire. The input current to the VFD could be as high as 20A for short periods, so wiring to the VFD would be recommended to use a minimum of 12G. As Rabler mentioned the manual specifies the recommended wire sizing, fusing/breaker, etc. Given your application, I would consider it a light duty VFD application.
 
OK. Thank you for that information.

Wolf emailed me and said the teco was out of stock and would possibly ship in 7 business days. I canceled the order. And ordered a 3hp version from Automation Direct. It was a recommendation in a different thread I found. The model is gs21-23p0.
 
I have done VFD installs with the Automation Direct GS21 VFD's, worked well and had no issues. Their software is also quite good for programming the VFD. If you need any help with the parameters, let me know. Should be a very simple install given you are using the clutch system, but may require some tweaking so that it won't fault when engaging the clutch.
 
I have a VFD and clutch. I noticed the same thing, The VFD overloads if I use the top hi speed gears. So i just avoid using them. I turn large diameter jobs. Also the amps go way up at hi rpms. Also I found that thinner head stock oil affects the clutch engagement and braking time.
 
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