VFD off the bay

At the moment I'm making good progress overhauling a recently purchased Tom Senior M1. In the near future I will need to purchase a couple of inverters. 1 1/2HP for the "S" type milling head. 1 1HP version for the main drive. Looking on the bay there are literally loads of far eastern drives. Has anybody got one of these versions in service ? Are they reliable ?

I would not recommend buying ANY mains powered device from any far eastern supplier on ebay, amazon bangood etc. I would definitely not buy a VFD from one.

You can have little or no confidence that it meets applicable safety requirements (Low Voltage Directive EMC Directive etc) or that it even meets it's specification. Buy a branded unit from a UK (or possibly EU) supplier. If nothing else you will have some one to complain to. If they don't have a proper UK address don't bother.

Robert G8RPI

I have 2 of them, one driving the main motor on the Bridgeport & one driving the X powerfeed. Both work fine and were very easy to set up. They have an internal fan so make sure there is plenty of free flow of air and protect them from swarf (I put mine in the original box that held the 3 phase electrical gubbins and vented the back with a mesh).

Robert

The post asked for recommendations from people who had already purchased and were using controllers bought off ebay, many of which are the same as sold by some electrical suppliers.

Emgee

Peter

"Reliable" is a very broad church. Industrial running every day at close to rated capacity is hugely different to occasional home shop use on a lightly loaded machine. Home shop types pretty much never approach the real metal shifting capacity of a machine, especially not industrial capable varieties, simply because dealing with large quantities of chips at high velocity is such a major league pain.

Issue with E-Bay import, whether "no brand" or "who they" brand, is that you don't know the standards of manufacture. Worse the E-Bay supplier generally doesn't either. Technical back up being essentially non-existent too. At best the inexpensive ones are devices from third or fourth tier makers. At worst a bunch of "surplus" standard line parts, which may well work but be below specified performance, assembled by outworkers in their back rooms. Things from the bottom end of the supply line probably haven't been turned on, let alone tested, before boxing up for dispatch. Which is worrying.

These days it can probably be assumed that the semi-conductor side of things is at least adequate, however marginally. So magic smoke release soon after purchase is rare. Although I'd be chary at running "no name" at its full rated capacity. The PCB boards on cheap import won't be up to industrial standards but should be good enough for the job. Probably unwise to let the shop get damp tho'.

For me the big issues would be the quality of the capacitors feeding the DC bus, how effective the safety components are, how good the control software is and whether or not the control software has actually loaded properly. Inverters are notoriously hard on their capacitors which are a consumable item needing periodic replacement after sufficient operating hours. For good quality ones probably more hours than home shop use will rack up. But first quality ones are expensive. Almost certainly the place where a lower end maker will shave quality. In practice probably fine unless they shave too far.

Fundamentally you just don't know for sure what you are getting. Something from a decent third or fourth tier maker ought to be more than good enough for home shop guy but at the back end of an E-Bay supply chain finding out what you actually have is hard. Heck some of the third and fourth tier brands have been knocked off by the build in a back room crowd. Just because the one Jack got at super bargain prices last year is still running fine it doesn't follow that the one you get will still be good. Jack might have been lucky, or hardly uses it, or its only on light duties or ....

Personally I can't be bothered with the risk. For me the objective real £sd difference in price between "has a good chance of being just fine" purchase off E-Bay and the real thing from Inverter Drive Supermarket or a similar supplier isn't worth the potential issues.

Your mileage, and depth of pocket may differ. Mine certainly would have done 40 odd years back when every £ really ought to have done the work of 5, or even 10 if I could manage it. These days I'm a bit more affluent and, at 65, have to seriously factor in how many good years I have left and what I want to spend them doing! Paying a bit more for "just works like it says on the tin" is attractive.

Clive

I bought one recently direct from China. Apart from the good price, it was the only one that I could see that had a removable keypad with a 1,5 mtr. extension so that the keypad could be placed close to the operator whilst the main unit remained safe away from flying swarf.

The unit I chose was a 1.5 kw or 2hp to power my TS Major.

The instructions were simple; 6 wires to connect, 1 for earth, 2 for live and neutral and 3 for the connection to the motor once swapped from star to delta.

The unit came with a variable speed control which I didn't think I would use but it has proved useful for running in the new motor and spindle bearings.

Cost; just £43 inc post. Like this one: https://www.ebay.co.uk/itm/1-5KW-2HP-220V-Single-To-3-Phase-Variable-Frequency-Drive-Inverter-CNC-VFD-VSD/202773455849?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649

Brian

Edited By Brian H on 26/11/2019 12:48:05

Hi Peter

I have purchased 2 from Ebay and have not had any problems with either. they are only used for a couple of hours at a time and work perfectly well for my needs

Mickt

I have run my Bridgeport for 6 years or more on a Huan Yang (spelling ?) VFD. It was sub £90 and has no issues. My friend who wired it for me has 5 of them running all his workshop requirements. I suppose I am a "Heavy user" compared to many home workshops using the mill 15/20 hours some weeks.

Not buying 'ANY' mains powered product from other than a UK or EU supplier is bit of a blanket statement. A far as I know eBay and Amazon are not far eastern companies although they do supply equipment manufactured in the far east.

I would not bother trying to buy something like a VFD direct from China or wherever, I would by a Chinese made one from an eBay seller, but only one that has UK stock. Actually its probably not easy to find many VFDs that are not made in China, which is where even all the big name brands get theirs made.

In the last 20 years or so I have used and fitted new and secondhand VFDs both cheap Chinese and expensive well known reputable brands. I cannot say that any have been unreliable, caused interference, or had problems of any sort. Documentation varies considerably but nowadays there is so much information and support online its not a problem.

Ian P

This forum has frequent cries for help by people who have an inverter, but no easy way to program it, they end up with a messy compromise. Good luck to them if they don't do any research and plump for the cheapest. I did a lot of research and have an inverter which works exactly as I wanted and has switches which are appropriate for a machine.

The inverter drive supermarket is not the cheapest, but has the choice of hundreds of inverters, and some have an invaluable extra, their own printable pdf of a quick start guide. This gives a variety of remote switch wiring and the easy programming for the most useful setup. If you want to struggle with an unintelligible set of instructions, then go ahead and buy cheap, I was glad I paid a bit more.

**LINK**

I have 4 inverters powering other machines in my workshop, all wired and programmed by myself. As old mart says Inverter drive warehouse have a super selection with documentation and switchgear, at the end of the day I will probably purchase a couple from them because of there back up. I asked the original question because I was astounded at the amount of Far Eastern versions on the bay. When I fitted the first inverter to my Super 7 about 10 years ago, you had to buy them from more specialist outlets.

I eventually chose a Schneider 0.75 Kw to power a 1hp six pole 935rpm motor in delta. The VFD is programmed to run from 25 to 75 Hz which gives from 467 to 1402 rpm, about 3:1 ratio.

**LINK**

I eventually chose a Schneider 0.75 Kw to power a 1hp six pole 935rpm motor in delta. The VFD is programmed to run from 25 to 75 Hz which gives from 467 to 1402 rpm, about 3:1 ratio.

I've no idea how this post doubled up. 

**LINK**

Edited By old mart on 26/11/2019 16:31:43

Edited By old mart on 26/11/2019 16:36:40

I resorted to a Chinese VFD when my expensive made in the UK inverter failed to run my Bridgeport. The UK back up was good but the machine would only run for a few minutes before tripping out and could not be resolved.

I seem to have upset some people with my comment about not buying from far eastern companies.

I did not say ebay or Amazon were far eastern or not to buy from them. I said "I would not recommend buying ANY mains powered device from any far eastern supplier on ebay, amazon bangood etc."
If you do, you are the importer and responsible for complying with relevant regulations. The VFD on ebay linked to by Brian H clearly does not meet CE requirements just from the photographs. It does not matter that you are not selling the unit or using it for business, you have to comply with the regulations. If injury or property damage results from the use of the item you could potentially find your insurance invalidated. I admit that this is highly unlikely to happen but it could. Apart from the legality issue, a large number of mains powered items sold by these sellers do not meet safety standards and many are downright dangerous.

I'm a professional electronics engineer and stand by my recommendation.

Robert G8RPI.

I have to agree with Robert, after spending my working life in the oil, gas and chemical industries as a Instrument and electrical engineer. Seeing a ribbon cable controlling a remote piece of equipment is certainly not up to spec. I will purchase equipment that is up to realistic standards and wire them up to equivalent standards.

+1 on Robert's comments. I have an Electronic engineering background but knew nothing about VFDs, when I was looking to convert my Chipmaster. I got great service, advice and a safe, quality product from Inverter Drive Supermarket. I was happy to pay a bit extra for this benefit.

I must admit that I missed the word 'on' in the Robert's statement about buying from eBay, Amazon etc which changes the meaning of what he was saying. I had also not seen the link to the cheap VFD on eBay. As far as I am concerned I would never in my wildest moments buy anything from a seller with that sort of feedback (120 negative in one month! and that's only from the buyers that bother to complain).

Having the VFDs original control panel on the end of a cable is of very limited appeal as its nowhere near as ergonomic as having robust switches and knobs on a proper pendant (or on the machines own panels.

For anyone not conversant with electrics I endorse all the previous suggestions regarding buying from the companies specialising in VFDs.

Ian P

I conclude from the answers given some 12 VFD's have been sourced from imports and are working without problem, no negatives from the users.

Emgee

+1, Huan Yang model bought from Banggood, checked over, powered up and running ok for past 3 years.