Newcomer to inverters, please advise.

[choochoo_balooParticipant @choochoo_baloo]

I am soon to receive a Senior M1 milling machine with the self powered S type vertical head. It's coming from a 3 phase workshop.

I've been advised by an electrical engineer I know that variable inverters for single phase domestic supplies offer the best of both worlds (compared to either just single or just 3 phase). He also said Transwave is as good a brand as any. However he is not a hobby machinist, so couldn't advise any further.

Before I contact Transwave, can any other inverter users outline what components I actually need? The machine has only the bare wire ends, no other electrical wizardry! I know very little about this subject.

Thanks in advance.

[choochoo_balooParticipant @choochoo_baloo]

[John HaineParticipant @johnhaine32865]

Apart from the inverter itself, ideally you need a mains filter and suitable screened 3-phase cable to connect the inverter to the motor. A nice-to-have is also a remote pendant to give stop/fwd/rev and variable speed. Easy to make yourself needing typically a single pole double throw switch and a 10k potentiometer – about a couple of quid from Maplin. In my case I fitted these into a box also containing a no-volt release switch that is the mains master switch for the inverter and also an e-stop button. If I understand correctly you will have 2 3 phase motors, only one used at a time. Therefore you may want a 3-phase plug and socket arrangement so you can connect the motor you are using to the inverter output.

I'm not sure what "compared to either just single or just 3 phase" means. Obviously you have to have a 3 phase output, but the input could be either single phase or 3 phase – the latter only really needed if you have a rather high power motor. A 13 amp single phase mains supply should be OK up to 3 hp I would think.

[Tim StevensParticipant @timstevens64731]

I found Transwave both helpful, and knowledgeable about the kit I was likely to have, and the problems I was hoping to solve. I would take photos of what you have, bare wires and all, and put yourself in their hands.

I have no connection with them except as a satisfied customer.

Cheers, Tim

[Gray62Participant @gray62]

+1 for Tims recommendation. Transwave are an excellent company to deal with and always helpful. Another satisfied customer.

[Chris Evans 6Participant @chrisevans6]

I run my 3HP lathe from a Transwave static inverter, around 5 years now and no problems. I tried running my Bridgeport mill from the same inverter with no success, the machine would run for a few minutes and then cut out. Pressing a reset in the machine electrics box restored use for another few minutes. Transwave where very helpful even coming out to the house to try and sort the issue but could not resolve it. A cheap ebay Chinese VFD all wired and set up by a friend cured the problem and it now just runs from a 13amp plug.

[David Hughes 3Participant @davidhughes3]

Have you had a look at the Newton Tesla site, They cover the Tom Senior milling machine with a variable speed control unit,

[not done it yetParticipant @notdoneityet]

It's coming from a 3 phase workshop.

240V three phase or 415V three phase? Start there.

[HevansccParticipant @hevanscc]

I did a refurb om my Tom Senior M1 (though without the S-type head), converted the 3 phase motor from Star to Delta and added an inverter. The thread is at this link

http://www.model-engineer.co.uk/forums/postings.asp?th=112156

Hywel

[John HaineParticipant @johnhaine32865]

Hi-ho. A standard 3-phase supply voltage is measured line to line, as a neutral may not be run to a load. The line-to-line voltage is 415V rms nominal. If you measure voltage from neutral to any one line it is 240V. 240 x square root of 3 is 415. So there is no difference.

[carl carleyParticipant @carlcarley97387]

worm gears – im looking for a largish worm gear and gear wheel its not important about the ratios, its more for an industrial look on this project, when i say largish im thinking the worm would be 3" long with an OD of about 1" and a 1/4" bore or large.

anyone think what gets scrapped with something like this in it?

[Brian HParticipant @brianh50089]

I found this company very helpful.

Brian

https://www.drivesdirect.co.uk/

[Chris Oakley 1Participant @chrisoakley1]

Hi

+1 for Newton Tesla.

My Myford went a tad smokey and Newton's plug & play replacement included a 3phase upgrade with variable speed.

[JonParticipant @jon]

Brian yes when he can be bothered to return your call, weeks later—-.
4 inverters later still using it, shame about the others cost me £1600.

Chris nearly went that way Oct 2017 then looked at their exorbitant prices, so much so bought motor from Scotland, Mitsubishi from Gloucester region and pod with the extravagant £20 odd delivery and still saved £80 after paying £25 for a filter.
They do not and will not set the invertor up for use.

[PlasmaParticipant @plasma]

Is buying an inverter and wiring it to a dual voltage motor a fairly straightforward thing or is it something best left to a professional?

Looking at transwave the packages look expensive compared to buying an inverter only.

I did email Steve Lilman at premier machine tools but he is I'll after suffering a stroke so unable to help.

Best wishes to him for a speedy recovery.

Mick

[john fletcher 1Participant @johnfletcher1]

Hello Mick, in general term the answer to your question it is easy. You can buy an inverter which will do almost every thing you will aspire to do via ebay for around £100. Four of my ME friends bought Huangyang inverters and have been very happy with their purchases.

I'm no expert here, but helped them to modify their lathes motor wise and to fit inverters. As for locating replacement motors, all four picked up second hand motors very cheaply, which only needed the brass links moving to convert from Star to Delta a 5 minute job. All four bought Huangyang inverters and have been very happy with their purchase.

iI you go down the HuangYang VFD route I'll send you a copy of the program which I used. By the way, there is thingy on youtube which explain the programing Huangyang inverters very well. I'm sure members will be only to glad to help you in any way as required.

As the control voltages are very low, a home brew control box can be made. Unfortunately Maplin has now gone which was a good source for variable resistors and switches. However, ESR at Cullercoats up the North East coast, have almost the same range of components needed. John

[John Paton 1Participant @johnpaton1]

I bought a variable frequency drive (inverter) from Honeywell Controls about 25 years ago for £80 including the programmer pad. It has been brilliant and never missed a beat. Best £80 I have invested in the workshop. The power , torque and quietness of the 3 phase motor combined with speed control and soft start is simply superb.

Go for it!

John

[sandy carsonParticipant @sandycarson76281]

I bought a Banggood A T1 inverter I need to increase the torque anyone know how to go about this ?? Regards Sandy.

[not done it yetParticipant @notdoneityet]

Bang good. Ugh.

The manual is on-line.

Good luck with your inverter.

[Anonymous]

As far as I'm aware no inverter measures torque, or directly controls it. So you can't increase it by just altering a parameter. The only thing that can be controlled is current which in simplified terms is proportional to torque. If you want more torque from a motor running at 50Hz then you will need to fit a bigger motor. If you want to boost torque at frequencies below 50Hz then you may be able to select a current profile that allows this, but be aware that it may hasten overheating of the motor.

I'm not familiar with Banggood inverters so I have no idea of the exact parameters that might need changing.

Andrew

[SteviegtrParticipant @steviegtr]

Posted by choochoo_baloo on 13/12/2017 18:58:57:

I am soon to receive a Senior M1 milling machine with the self powered S type vertical head. It's coming from a 3 phase workshop.

I've been advised by an electrical engineer I know that variable inverters for single phase domestic supplies offer the best of both worlds (compared to either just single or just 3 phase). He also said Transwave is as good a brand as any. However he is not a hobby machinist, so couldn't advise any further.

Before I contact Transwave, can any other inverter users outline what components I actually need? The machine has only the bare wire ends, no other electrical wizardry! I know very little about this subject.

Thanks in advance.

Have a look at the motor rating plate to see if it is dual voltage. Meaning the windings are 240v or therabouts. If it only says 415v it will not accept a single to 3ph inverter. If you did use a said item you would have very little power. Some have said you can buy a single phase in 3 phase out at 415v, but i have never seen one. I searched the net & found none too. But there are members who say they have them so they must exist.

Steve.

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