Inverter Welders

[EdDekker]

The wiring diagram for the remote plug is in the Dynasty manual.

The connector used by Miller for the 14-pin remote connection is an Amphenol #97-4106A-20-27-P, with strain relief #97-3507-12. These connectors are made by both Amphenol and AMP. Expect to pay about $20 for the connector and $8 for the strain releif for the metak shell connector. (Miller is now using the plastic shell version.) You will also need the contact pins.


You can order them from an electronics supply house which deals with AMP or Amphenol connectors. (Powell Electronics 800-235-7880, TTI Electronics 800-225-5884, Arrow Electronics 800-388-2277, AVNet Electronics 800-332-8638, or Newark)



Sources for 14-pin connectors Google thread from sci.engr.joining.welding

 

[centex]

Ed, thanks for the information about the connector. That should save me a few dollars. In the whole scheme of things it is not a lot but at least I don't have to buy something with a 10 times or more markup. I had looked at the wiring diagram in Dynasty manual. One thing that bothered me was a couple of extra feedback signals which could mean that the current control is more than just a potentiometer but I can't see why it would be anything more. Unfortunately the manual for the foot control is not available online. If you have the RFCS-14 foot control, would you see if there a schematic in it's manual and let me know if the current control is more than a potentiometer?

 

[EdDekker]

The Dynasty/Maxstar manuals don't have any description beyond the signal name, and they are ambiguous. I interpreted them to be outputs from the welder indicating the instantaneous voltage and current being supplied by the welder.

The manual for the RFCS-14HD shows a contact switch between A & B in the amphenol plug. A 1000 ohm, 2 watt potentiometer is connected to pins C, D, and E with E being the wiper. There are bypass (Ceramic disk) capacitors between pins C and E and between pins E and D. The value of the capacitors is not specified in the manual. There is no connection to the Feedback pins (or any pin other than A B C D and E.



A post to the Hobart forum will get a definitive definition of the feedback pins from the Miller Support guys who hang out on that forum.



You may be interested in photos of a converted sewing machine pedel are at the bottom of this web page.

 

[centex]

Ed, thanks for the info. All I have to do is wire my Linde foot pedal up to a Miller plug and maybe paint it blue. Those are interesting pictures on the web site. It is a far cry from the electronics in my old TIG welder. They fit on two small 3"x5" boards that are almost too small to see among the huge transformers and inductors. I learned enough from the posts in the news groups to convince me that the Dynasty 200 is much to new a product to buy at this time. I may go for the Dynasty 300 since it has been in production long enough for the early production bugs to be worked out.

 

[Anonymous Poster]

Well, if anybody hasd a foot control on the shelf for an old P&H, give me a shout. It's a large ugly aluminum casting with a huge ceramic block resistor about 6 x 8 inches and a wiper.
I'll happily trade for an old Airco foot control that can easily be modified for Miller.

BTW, I also loved the small Linde MIG machines.

 

[EdDekker]

The XMT 304 is the Miller inverter welder which predates the Dynasty. A version of this welder is still in production, but I suspect they have made a few changes to reduce the parts count.

Did you see the REALLY old High Frequency units elseware on that web site? web page They are all transformer, inductor, capacitor and spark gap.

 

[centex]

I have a Linde 225A MIG welder that I bought in 1981 that still works great. I love it too. I liked the Heliarc 250HF too until it quit. It used a saturable reactor and really did well on thin aluminum. I bought a used Miller Synchowave 250 today and spent most of the day swaping the running gear from the Linde to the Miller. I tried it out on some thin aluminum. Even though it is a squarewave machine it does not do any better than the old Linde on low current AC welds. If anything the Linde did better than the Miller. The Miller does not have the power factor correction capacitors in it so I think I will have to buy them. It takes 4 120 uf capacitors. The Linde had a special winding on the main transformer that let it get by with only 2 60uf capacitors. I may have to keep looking for the parts so I can get it working again.

 

[centex]

There is not a lot they can do to reduce the parts count. These inverter welders are not much different than the swithing power supples that we use in computers today. They use a lot of parts but only small transformers. The size and weight and cost of the old power supplies was in the large transformers. The question I have is since the inverter welders should be less costly to manufacture why do they cost twice what the older more expensive technology does? I suspect that they are trying to recoup their development expense and the cost will come down in a couple of years.

The non-inverter TIG welders made today still use spark gaps. Supposedly the spark gaps produce RF interference that can affect nearby TV's, radios, and cell phones but I have been using one for over 20 years and my wife has never once complained that it interfered with her communications gear. She does complain that I spend too much time in the garage. The spark gaps have to be adjusted periodically as they wear away with use although it takes a lot of use to make them stop working. I don't really see why the high frequency AC welding currents in the new machines would produce any less interference or for that matter why they would not produce more interference.

 

[wroughtn_harv]

Morning Don,

I have found a new friend. He's an old guy in the country that's more clever than that bird family Hakim's got the thread about pilfering the quarters.

He has a Miller Syncrowave two fifty something or another. It's brand new with a torch. It's never been lit. He says it retails for forty one hundred without the torch. He wants three grand for it complete.

This guy is totally neat. I'm going to write a piece on him with photos for the fans of clever thought here at tbn. He's only sixty nine and still clickin' on about nine of ten cylinders.

If you're interested I can post a picture or two of it for you and get the two of you together. Now that would be a match made in heaven. /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif

 

[centex]

Harv, I bought one of these machines last week from a local business that closed up shop otherwise I would take you up on this. I still plan to buy a new inverter welder in a year or so because of their light weight and low input requirements. I did not buy one now because I think they are still too new to put that much money in. Thanks though.