Generators and Electric Motors
[Home] - [HELP] - [Forums] - [Groups] - [Classified Ads] - [Subscribe] - [Books] - [Sponsors] -

Go Back   SmokStak > SmokStak® Shop Equipment Tools and Techniques > Welding Shop
Forgot Password? Join Us!

Notices

Welding Shop Welder generators, equipment, weld practice, techniques, troubles and solutions. See our TERMS of SERVICE prior to reading!

Welding Shop

Miller 330 A/B/SP


this thread has 14 replies and has been viewed 3008 times

Reply
 
Thread Tools Display Modes
  #1  
Old 12-22-2015, 05:36:17 PM
ramsay ramsay is offline
Registered
 
Join Date: Jul 2008
Location: Port Allen, Louisiana USA
Posts: 35
Thanks: 0
Thanked 3 Times in 3 Posts
Default Miller 330 A/B/SP

Hello everyone: I recently acquired and old (1969) Miller single phase stick/tig welder serial number U470001...Miller cannot supply me with the right manual for it as they do not go back that far...


Can anyone help me out with a manual also how about parts? I need some capacitors for the spark gap.. Mike in Louisiana
Reply With Quote
Sponsored Links
  #2  
Old 12-23-2015, 07:13:42 AM
dkamp dkamp is offline
eMail NOT Working
 
Join Date: Oct 2007
Location: LeClaire, Iowa, USA
Posts: 1,733
Thanks: 34
Thanked 934 Times in 605 Posts
Default Re: Miller 330 A/B/SP

They're simple and similar enough that just about ANY 330 A/B-P manual will suffice...
Just go here:
https://www.millerwelds.com/support/manuals-and-parts

Scroll down the list, and choose 330 A/B-P or A/B-SP.

The HF circuit system uses around 0.0004uf at anything over 4kv, with a mica transmitting capacitor being the most durable for the application. I used a Sangamo 0.004uf/10kv unit from my HAM radio junk box.

If the value is lower (say just 0.0002uf) the output frequency will be higher, and if higher (like 0.0006uf) it'll be lower in output frequency. Adjusting the arc contacts wider will change the frequency as well, but frequency isn't critical. The voltage rating will determine the capacitor's lifespan, so go with one rated as high as you can find and make fit, and it'll last longer. IMO, 4kv was probably low, as these tended to break open and bleed goo when they worked really hard. Bein's that it's a wide-band oscillator, it probably generated RF voltages a fair amount higher than 4kv at times.

Oh, and you'll probably find that Miller won't 'list' it as still being a stocked item... an OLD dealer MAY have new old stock around that's no longer shown 'on inventory', so you'll have to carry it in and ask. The OEM Miller component on MINE had absolutely no markings in the value fields, just a miller part number inked on the side, so if yours has none, it's the original unit... the original package is referred to as an 'F2' or "CM-70" form factor:

https://www.surplussales.com/Capacit...sB-E-CCap.html

BTW... 0.0004uF is the same as 400pF.

A pair of 200's is what WAS in it, but A single 400pF will work nicely as well:

(CFT) F2B00400BRA 400 pF 5 kv 3 amps F2 style

Last edited by dkamp; 12-23-2015 at 07:26:25 AM.
Reply With Quote
  #3  
Old 12-24-2015, 12:22:15 AM
ramsay ramsay is offline
Registered
 
Join Date: Jul 2008
Location: Port Allen, Louisiana USA
Posts: 35
Thanks: 0
Thanked 3 Times in 3 Posts
Default Re: Miller 330 A/B/SP

Hey thanks for the speedy reply! Both of the caps were missing in mine but I think they were originally .002 uf at 6000 v... It appears that what is used now is the same uf at 10,000 v and I suppose just one instead of two.. Looks like they want around 90 bucks or even more for one.. I found a manual online and it is a military manual which corresponds with the milsurp unit I have made in 1969...Thanks again and Merry Christmas!
Reply With Quote
  #4  
Old 12-24-2015, 09:32:25 AM
dkamp dkamp is offline
eMail NOT Working
 
Join Date: Oct 2007
Location: LeClaire, Iowa, USA
Posts: 1,733
Thanks: 34
Thanked 934 Times in 605 Posts
Default Re: Miller 330 A/B/SP

Good deal!

Yes, actually, Miller has a very, very good online source for owner's manuals and parts books... all one needs to know, is that Miller not only made their own, but they made machines that were branded and sold by others, AIRCO being one of the frequents.

The HF arc starting system is actually very simple, and by today's standards crude, but incredibly effective. in contrast, the A/B-P's relay control 'tree logic' is more complicated... like a pinball machine of sorts, and there's a few places where strange things go wrong and leave a guy confounded, but I'm speaking from experience here... At this very moment, I've got an Airco A/B-P with covers off in my shop, and I'm getting it set up with plumbing for water cooler and gas, so if you hit a brick wall, drop me a private message with your phone number and I'll talk you through it while you've got your hands on it.

The capacitance is fairly forgiving. Two 200pF 6kv caps in parallel (as per factory setup) yields 400pf @ 6kv. If you put just ONE 200pf in, it'll work, but the HF coupling inductor (T3) and the HF power sourcing transformer (T4) are designed to be most effective with 400pf and a 0.004" to 0.013", with best being around 0.008". Running less or more capacity will alter the gap, and also affect the service life of the arc gap rods' tungsten faces. You'll know when the HF unit is working... the sound-and-fury is unmistakeable.

Other things of note- the control relay 'tree' (of CR 1,2,3,4) is located under the black cover on right-hand side (remove top and side panel for access). The delay timer is up on the front panel, under the HF starter panel, between the gas/water valves.

The units had some variation in provisioning, some have automatic features, some don't, so don't be surprised if the docs don't match exactly what you have... provisioning options were by customer-order. Likewise, they can be configured for a variety of different operations, there's jumpers to 'set it up' for whatever the owner desired. If yours isn't working 'right', make sure you check all the configurable jumpers to make sure it's not set for some other operational mode.

Also, if it wasn't already somewhat confusing, the wiring was easily 're-engineered', so guys COULD make them do 'special' tricks... the giveaway is any 'non-original' looking wiring, in which case, get familiar with the wiring diagram, and start tracing wires and wire-numbers.
Reply With Quote
  #5  
Old 12-24-2015, 01:25:48 PM
ramsay ramsay is offline
Registered
 
Join Date: Jul 2008
Location: Port Allen, Louisiana USA
Posts: 35
Thanks: 0
Thanked 3 Times in 3 Posts
Default Re: Miller 330 A/B/SP

Hello and thanks again for your reply! I have yet to get a cap for the spark gap but I have taken the side panels off to check for other things and everything looks really nice.. I have not found any dark insulation or anything of that nature.. The rectifier looks like brand new even....
There is supposed to be a big square can cap on each side of the machine and I have one on the right side facing and on the left side facing there are two round caps taped together with wires on them.. Are these pf caps? I have not checked them yet but I do have an instrument to check caps with.. I think they are supposed to be 30 mfd at 600 volt....

I have a small Miller hf unit with a spark gap on an old Idealarc and it seems to have pretty much the same guts in it that the 330 uses in the hf section...

Thanks for the advice and also for the offer of a phone call.. I may well have to take you up on it before this thing is up and running.. Mike in Louisiana
Reply With Quote
  #6  
Old 12-24-2015, 09:11:46 PM
dkamp dkamp is offline
eMail NOT Working
 
Join Date: Oct 2007
Location: LeClaire, Iowa, USA
Posts: 1,733
Thanks: 34
Thanked 934 Times in 605 Posts
Default Re: Miller 330 A/B/SP

Mine doesn't have any large caps on the outside... so I'm not sure what you're seeing. Snap some pix of what you're looking at and post them. In the parts section of the manual, you'll see that they idenfity each item with a numbered callout, and in the parts list, it identifies the component ID (i.e. R2, C5, CR3, etc) so it's not difficult to identify what each component does. Don't be surprised if your unit doesn't have some-particular-part that you see in the diagrams- they included most of the common permutations, and simply omit (and as necessary, jumper around) what isn't used. For example, mine doesn't have the SPOT welding function, so TR2 doesn't exist... nor does the SPOT switch and wiring.
Reply With Quote
  #7  
Old 12-24-2015, 10:56:33 PM
ramsay ramsay is offline
Registered
 
Join Date: Jul 2008
Location: Port Allen, Louisiana USA
Posts: 35
Thanks: 0
Thanked 3 Times in 3 Posts
Default Re: Miller 330 A/B/SP

30 mfd caps are under the side panels however on the left side someone has changed to two round caps.. I ordered two new run caps 30 mfd 460 volt from ebay as replacements.. The one on the right side lower is a large square can type...Mike in Louisiana
Attached Thumbnails
Click image for larger version

Name:	DSC00002.JPG
Views:	105
Size:	94.4 KB
ID:	242184   Click image for larger version

Name:	DSC00003.JPG
Views:	118
Size:	87.4 KB
ID:	242185  
Reply With Quote
  #8  
Old 12-28-2015, 02:31:44 AM
dkamp dkamp is offline
eMail NOT Working
 
Join Date: Oct 2007
Location: LeClaire, Iowa, USA
Posts: 1,733
Thanks: 34
Thanked 934 Times in 605 Posts
Default Re: Miller 330 A/B/SP

Okay, so on the left side, where you have round cans, used to be two oval cans, on my diagram OM340 Page 1, is callout #5, C1 30uf 460v... and it's in series with an apparently dedicated winding of the main transformer's primary.

Because of how it's located, I don't THINK it was for power-factor correction... my guess is that the dedicated winding, and capacitor are probalby there to quench any high-frequency noise that would otherwise have made the trip backwards through the MT's core... probably generates enough loss at any frequency above 100hz to effectively stop RF from wandering back towards the source.

And I appreciate you asking that, because I got my Airco to fire off a nice output, with plenty of HF, and while the input current demands of the machine seem very low, it's still tripping my subpanel's main breaker. i've double-checked the hot and ground legs, and found that there's no overcurrent condition, but the HF component finding it's way back is most likely causing the breaker to respond either by magnetism or heat, so I'll be checking C1 out on mine, too.
Reply With Quote
  #9  
Old 12-28-2015, 01:08:33 PM
ramsay ramsay is offline
Registered
 
Join Date: Jul 2008
Location: Port Allen, Louisiana USA
Posts: 35
Thanks: 0
Thanked 3 Times in 3 Posts
Talking Re: Miller 330 A/B/SP

Hey didn't think about the idea of those caps being for hf protection.. I ordered two new 30 mfd 460 volt run caps to replace the ones on the unit.. The old square can was running around 29 mfd on my test instrument whereas the round caps someone put on the other side were running about 25...Still haven't gotten a hf cap for the spark gaps... I did however find the correct mil manual for the machine.. It is milsurp from 1969...Mike in Louisiana
Reply With Quote
  #10  
Old 12-28-2015, 02:08:41 PM
ramsay ramsay is offline
Registered
 
Join Date: Jul 2008
Location: Port Allen, Louisiana USA
Posts: 35
Thanks: 0
Thanked 3 Times in 3 Posts
Talking Re: Miller 330 A/B/SP

It appears that originally there were four big cans in the military unit I have...They wired just like the commercial unit to lead 15 and 25 but they appeared to be paralleled ...This was probably due to the military use of high frequency radio communications... The commercial unit shows to have one cap on the 200 amp unit and two on the 300 amp unit.. Mike
Reply With Quote
  #11  
Old 01-03-2016, 01:30:04 PM
dkamp dkamp is offline
eMail NOT Working
 
Join Date: Oct 2007
Location: LeClaire, Iowa, USA
Posts: 1,733
Thanks: 34
Thanked 934 Times in 605 Posts
Default Re: Miller 330 A/B/SP

Yeah, probably. I can't imagine that it'd do much to reduce the RF hash in near-field, but it MAY be that they were doing whatever they could to reduce RF returning to the source, if for no other purpose than reducing nuisance trips from HF in the breaker.

For what it's worth... HF supply power comes off the secondary of the main transformer, and NO contact of CR2 is in the circuit of the secondary's power feed, right after the Start-off-continuous switch...

...BUT... CR2 is dependant upon CR1 (the output detection sensing) in the DC output leads. CR1 on MINE is like... 28vdc, and CR2 is 120v DC. They've arranged a bridge rectifier (that's in the top left corner- a selenium stack) with capacitor to serve as a 'delay' scheme for HF START... so you have to have CR1 pulled in, THEN CR2.

CR1 and CR2 look identical to CR3 and CR4 (which are both 120vac coils). If someone mixed these up in a replacement, they may not work (at the least) and may be fried (at worst).

I'm not sure what's up with mine... I can get HF, but the delay is wonky, and my post-flow timer is cooked, so I'm gonna try reconfiguring it with a quartet of ICM 102B timers and repeater relays. Hopefully they won't be too fussy about being 5" from an arc gap. ;-)
Reply With Quote
  #12  
Old 01-05-2016, 01:01:33 PM
ramsay ramsay is offline
Registered
 
Join Date: Jul 2008
Location: Port Allen, Louisiana USA
Posts: 35
Thanks: 0
Thanked 3 Times in 3 Posts
Talking Re: Miller 330 A/B/SP

Haven't done much more with mine except I got some new capacitors to replace the can and round ones.. I noticed however that the orange coating is flaking off the big rectifier in the top of the machine.. I sure hope this is not a serious thing.. It was welding fine with stick before.. I know because I welded with it recently.. Mike
Reply With Quote
  #13  
Old 01-07-2016, 12:56:27 AM
dkamp dkamp is offline
eMail NOT Working
 
Join Date: Oct 2007
Location: LeClaire, Iowa, USA
Posts: 1,733
Thanks: 34
Thanked 934 Times in 605 Posts
Default Re: Miller 330 A/B/SP

All the rectifiers in mine are selenium stacks... which is to say, they're not all that 'popular' to use anymore, and I'd be surprised if they're available at any reasonable price. Fortunately, replacing them with modern high power silicon diodes is not difficult... the only challenge being cutting aluminium plates and mounting them on insulators to provide heat-sink surface... and that's not a difficult thing to do for most of us.

Advantage to changing them to silicon, is that the operating characteristics of silicon diodes are much more efficient than selenium... so less heat generated... and you'll likely have higher output... but the flaking paint isn't a sure sign of anything other than failing 4-decade-old paint, so carry on!
Reply With Quote
  #14  
Old 01-07-2016, 11:29:16 AM
ramsay ramsay is offline
Registered
 
Join Date: Jul 2008
Location: Port Allen, Louisiana USA
Posts: 35
Thanks: 0
Thanked 3 Times in 3 Posts
Talking Re: Miller 330 A/B/SP

Hey thanks! I have been doing other things in the shop.. Fixing up a large drill grinder so haven't been on the welder project much.. I have the two 30 mfd caps now and have the .002 cap for the spark gap on order. Anxious to see how well it all works..

I have an old idealarc from about 1957 with a Miller hi freq unit attached .. Been using it for years for a stick machine.. May replace that unit altogether with the miller who knows? Mike
Reply With Quote
  #15  
Old 01-10-2016, 01:52:12 PM
ramsay ramsay is offline
Registered
 
Join Date: Jul 2008
Location: Port Allen, Louisiana USA
Posts: 35
Thanks: 0
Thanked 3 Times in 3 Posts
Talking Re: Miller 330 A/B/SP

I looked at a schematic wiring diagram for a miller dialarc 250p without hf... Looks like the transformer has the same capacitor winding as the 330 .. Two dialarc models were offered.. The 250P is the power factor corrected model and uses two 40 mfd 460 volt caps.. The standard 250 dialarc does not have that circuit and draws more current, 90 vs 68 amps for the "P" model on 240 volt..

The Miller 330 uses 30 mfd caps at 460 volt in the same type of dedicated winding in the transformer...

I bought a new 250p in 1987, don't have the machine anymore, and still have the book for it..Gonna pass it along to a friend who has one. .Mike in Louisiana
Reply With Quote
Reply

Bookmarks


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

F o r u m Jump

Similar Threads Chosen at Random
Thread Thread Starter F o r u m Replies Last Post
Miller Tire williamgrgn Antique Farm Tractors 0 08-19-2015 09:42:27 PM
Ron Miller Oilpulled Antique Steel Wheel Tractors - Old Iron Lugs and Cleats 8 03-01-2012 12:50:19 AM
Miller Big 40 lorenzana Welding Shop 2 07-01-2010 01:22:47 PM
Anyone Know Don Miller? Bodo Luehmann Hit & Miss Gas Engine Discussion 6 11-05-2009 04:32:57 AM
Miller 351 JNorton Welding Shop 3 06-29-2007 10:40:13 PM


Use "Ctrl" mouse wheel to change screen size.
All times are GMT -4. The time now is 01:52:31 PM.

Smokstak and Enginads site search!


All use is subject to our TERMS OF SERVICE
SMOKSTAK® is a Registered Trade Mark - A Community of Antique Engine Enthusiasts
Copyright © 2000 - 2019 by Harry Matthews P.O. Box 5612 - Sarasota, FL 34277