3 phase static converter from 240v

[sweepy]

I have a problem that's driving us all mad.

3 machines from a school workshop; all been running on 415 3 phase. trying to get them to run in a small workshop on a domestic 240 supply (6mm feed from house). Machines are small pillar drill, small Startrite Inca planer/ thicknesser and a Union graduate wood lathe. We are trying to get a Clarke PC60 Inverter to run them one at a time. Each machines rating is well within even half of the 5.5hp capability of the pc60, but we keep getting variable or no outcome. Sometimes get planer working for 10 secs or up to 2.5 mins. Same with other 2 but usually only up 30 secs before the current overload in the starters cut in. Various people have looked at the set up but no one can work out why they all cut out. Occasionally they will not even start up. Have gone through the 'chatter stage' and direction feed changes. Even took the overload off the pillar drill (ran it direct off 415 and it ran ok).
Pc60 is supposed to have auto boost on startup. Sometimes we hear it (thunk) other times not. Supposed to try starting on lowest of the HP settings and move up until it starts happily (to keep startup current at their lowest). Even these settings can change.
We have also borrowed an old Boost Energy converter, and are getting the same results: cannot get them to work or stay on longer than a few seconds
Hope that this makes sense. All advice greatfully received.
Thanks
Sweepy

 

[john999uk]

Have you measured the input voltage at the inverter during startup and after. Then measure output voltage.

 

[john999uk]

Have you read the instructions re chatter? Says control circuits should be fed from L1 & L3. If control circuits are 230vac then you need a separate feed!

 

[sweepy]

Thanks for replies,
No not checked input voltage. presumed it would be standard for here 230v. On 6mm cable over 30 metres. Calcs show only a few volts drop. No lights dimming on startup.
Yes, read chatter instructions. They are set on L1 and L3. There were no extra cables inside the starter box. had been cut off outside. 99% sure 415v. Think overload been taken from one of the phases.
Cheers

 

[john999uk]

If you are unsure of input voltage, as in you have not tested it I would suggest that you may not have the equipment to test your voltages. Mains voltages are dangerous, I would suggest you post your location and see if a spark on here is local and could come and help. Maybe best to wait till after festive time as rates will be cheaper.

 

[sweepy]

Had a qualified sparky here last week. He did not suggest the test. We did check current on start up of planer and as it cut out. Went a bit haywire as it was cutting out and peaked about 1k. We put it down to the contacts opening on the overload.

 

[john999uk]

Reason I suggested input voltage test during startup was to see if the voltage was dropping due to the load. By the sound of it you have visually inspected it but without testing the voltages it's difficult to determine what is happening.
Sorry to say but I still think you need someone who is competent to fault find on the 3phase kit you have.

 

[guest119]

Voltage issue for sure.
Was on a remote water site last week and it had a sp+n supply which went to an invertor, came back as 350v phase to phase as one phase to earth was only 200v.
This from a professional piece of kit which still managed to run its pumps.
I have yet to find a C...ke piece of kit which does what it says on the tin.
You say your overcurrent coils are tripping, dont you mean your no volt coils? Therefor stopping it from latching.