Announcement

Collapse
No announcement yet.

50A breaker or 60A breaker for Lincoln AC/DC 225?

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • 50A breaker or 60A breaker for Lincoln AC/DC 225?

    I wired my new detached garage shop with a 220V (or 240V) circuit with 6awg stranded copper circuit for a "future" welder, not knowing what welder I might go with, thinking 50A would be adequate.

    I have 200A service to the house and 100A between the house and shop but the county requires that it be breakered at 90A.

    Now I'm gravitating toward the Lincoln AC/DC 225, for which the Lincoln website recommends a 60A breaker.

    I'm finding discrepant info on the web. Hoping to get some pearls of wisdom from the HSM forum members. Will check with my electrician next week, just doing due diligence now.

    Questions:

    1. Getting some conflicting info as to whether I have 220V or 240V here in southeast Michigan. One source claims that only 240V 1 ph is available in the USA. Can't find confirming data. Can anyone confirm? I think I saw on the Lincoln website that a 50A breaker is recommended for 240V. If so my problems are over.

    2. Ampacity for 6awg wire is called out as 55A, but apparently going with the next "common" size breaker is legal. Can anyone concur here?

    3. With the 20% duty cycle spec on this welder, it amounts to a safety factor, and a comfortable margin on the circuit. True?

    4. Can I just go with a 50A breaker, and live with the possibility of blowing the breaker on heaviest welding loads?

    5. If I've shot myself in the foot with the 6awg wire with respect to the Lincoln AC/DC 225, which other stick welder would be adequate for fabricating moderate size steel pipe and bedframe type material? At this point I'm not inclined to spend more than a few hundred dollars on a used welder, until I know I want to pursue this interest further.

    I know I can always drag bigger wire but it would require some tear up I'm not sure I want to do, before I know I want to pursue this interest further.

    Any insight gratefully received.
    Last edited by jmarkwolf; 01-30-2015, 09:14 PM.

  • #2
    1. Get a voltmeter (cheap at HF) and find out what voltage you have. Mine varies from day to day in a rural area, but usually around 220v.
    2. Because of the duty cycle, especially on a stick welder probably #10 would be adequate but I would go with #8. #6 all the better!
    3. As I understand it, the duty cycle allows a smaller wire size because it doesn't heat up like it would under a 100% duty.
    4. I have used a 50A breaker on my tombstone welder and never had an issue. I have tripped the internal breaker when doing hot and heavy welding and had to let it cool down. I have also used a 30Amp dryer outlet and breaker when I lived in rentals and never even had an issue unless using larger rod sizes.
    5. Your welder is great for general purpose welding, although because of the fixed amperage settings in may be difficult to do out of position welding.
    Last edited by cijuanni; 01-30-2015, 10:11 PM.

    Comment


    • #3
      I have run my welders(formerly a Lincoln SP250 now a Millermatic 252 and a Syncrowave 250) on a 50 amp circuit for 20 yrs without one issue or blown breaker.
      My guess is your meter will read about 230 volts.

      Comment


      • #4
        FWIW, I think you will be fine with the 50amp breaker.

        Comment


        • #5
          We ran a Lincoln AC/DC 225 on a 50 breaker on the farm for years, and it welded some pretty stout stuff.
          Mike
          Central Ohio, USA

          Comment


          • #6
            Mine runs off a 40amp breaker on #6 wire (40 amp is biggest breaker i can get for my panel). Burned many pounds of rod, never tripping a breaker. My little mig (hobart 140) on the other hand needs a dedicated circuit though (have yet to do it) because it trips a breaker all the time. My entire garage runs off one circuit so I've got to be carefull what i have on when i run it.

            Comment


            • #7
              3. With the 20% duty cycle spec on this welder, it amounts to a safety factor, and a comfortable margin on the circuit. True?
              Not true, by my understanding. Duty cycle describes what proportion of time out of 10 minutes the welder may be operating without over heating, but does not address the current draw at any given instant, which is what will trip the breaker.

              Having said that, 1) yes see what your actual local voltage is. It may be anywhere from 220 to over 240 depending on which part of the country you are in. You could also check with your power company. and 2) Most who have responded think a 50 amp breaker will be fine, and my guess is that this is correct.
              "A machinist's (WHAP!) best friend (WHAP! WHAP!) is his hammer. (WHAP!)" - Fred Tanner, foreman, Lunenburg Foundry and Engineering machine shop, circa 1979

              Comment


              • #8
                Originally posted by mickeyf View Post
                With the 20% duty cycle spec on this welder, it amounts to a safety factor, and a comfortable margin on the circuit. True?
                Not true, by my understanding. Duty cycle describes what proportion of time out of 10 minutes the welder may be operating without over heating, but does not address the current draw at any given instant, which is what will trip the breaker.
                It's slightly more complex than that.

                You can run a 50 amp load on a 40 amp breaker for quite a while before it will trip. You can also run higher than rated loads (within specified limits) without harming the wiring IF the wiring has a chance to cool off every few minutes. These two facts are why the NEC allows a "welder only" circuit that is used for only one thing, a welder with a known duty cycle. The greater your duty cycle, the bigger your wire (and breaker) need to be to protect against fire.

                You should be able to find a chart that shows the duty cycle at each output. There is an NEC chart that will then cross reference the draw (in amps) and duty cycle to the breaker / wiring size.

                In this specific case, the smartest thing is to follow the manufacturer's recommendation. You can be sure that Lincoln has researched it and made sure that it was safe.

                Dan
                At the end of the project, there is a profound difference between spare parts and left over parts.

                Location: SF East Bay.

                Comment


                • #9
                  I think you will find the voltage, whether 220, 230 or 240 to be a non issue.

                  Where are you finding ampacity for #6 at 55 amps? My admittedly ancient codebook lists #6 thhn with 3 wires in raceway or cable etc., at 65 amps. TW is rated at 55 amps, so maybe that is what you saw?

                  Dave

                  Comment


                  • #10
                    Originally posted by becksmachine View Post
                    I think you will find the voltage, whether 220, 230 or 240 to be a non issue.

                    Where are you finding ampacity for #6 at 55 amps? My admittedly ancient codebook lists #6 thhn with 3 wires in raceway or cable etc., at 65 amps. TW is rated at 55 amps, so maybe that is what you saw?

                    Dave
                    Hi Dave

                    See attached,.

                    Yes TW & UF column is what I was looking at. Admittedly, I'm not sure what those are, I just went with the most conservative number. My wire is MM-B 6-2 W/G 600V Cirtex - A. It's stapled to the studs, and the run from the panel is approx. 25ft. This is what the electrician recommended I get when I told him I wanted a 50A circuit for a welder.

                    I selected 50A because this is what a welder buddy of mine has for his dedicated TIG circuit. At the time I didn't know what welder I might end up getting.

                    The Cirtex datasheets also cites my specific 6awg wire is good for 55A.

                    Please advise.

                    [IMG][/IMG]
                    Last edited by jmarkwolf; 01-31-2015, 05:25 PM.

                    Comment


                    • #11
                      I found a PDF at http://www.homedepot.com/catalog/pdf...0bedb4844a.pdf that tends to indicate the wire is rated 90c, so 75 amp?

                      Sounds like a winner.

                      Dan
                      At the end of the project, there is a profound difference between spare parts and left over parts.

                      Location: SF East Bay.

                      Comment


                      • #12
                        Originally posted by danlb View Post
                        I found a PDF at http://www.homedepot.com/catalog/pdf...0bedb4844a.pdf that tends to indicate the wire is rated 90c, so 75 amp?

                        Sounds like a winner.

                        Dan
                        Well no, not a winner.

                        The wire itself might be rated at 90° C, but it is highly unlikely that the connections to the wire are. The normal screw clamp connections are usually rated for 75؛ so you have to use that rating That pdf is very confusing as they have all this 90؛ stuff, but you will notice that all the accompanying tables us the 60؛ ratings.

                        Originally posted by jmarkwolf View Post
                        Hi Dave

                        See attached,.

                        Yes TW & UF column is what I was looking at. Admittedly, I'm not sure what those are, I just went with the most conservative number. My wire is MM-B 6-2 W/G 600V Cirtex - A. It's stapled to the studs, and the run from the panel is approx. 25ft. This is what the electrician recommended I get when I told him I wanted a 50A circuit for a welder.

                        I selected 50A because this is what a welder buddy of mine has for his dedicated TIG circuit. At the time I didn't know what welder I might end up getting.

                        The Cirtex datasheets also cites my specific 6awg wire is good for 55A.

                        Please advise.

                        [IMG][/IMG]
                        Ok, I see where you are coming from here. I am used to working with individual conductors in conduit not the non-metallic Romex style wire.

                        Unless you run afoul of some particularly pedantic regulatory silliness, you shouldn't have any problems running that welder on your existing set up.
                        I would try the 50 amp breaker to begin with, knowing that if you have a problem with nuisance tripping you would still be complying with code to try and see if a 60 amp breaker solves that problem.

                        Dave

                        Comment


                        • #13
                          Well, let's see.

                          I've got the same Lincoln AC/DC 225 tombstone. I wired up a receptacle right net to the breaker box, with 6 gauge wire and 50 amp breakers. I can't find the info now, but as I recall that met Lincoln's recommendations.

                          To allow me to use the welder at a distance from the outlet, I bought a 25' 8 gauge extension cord - the heaviest my welding supplier had, and what they recommended.

                          So far, so good. It's my understanding that while the 8 gauge cord might be marginal if enclosed within a wall, it's fine as it is used in the open where heat is not a problem. Maybe I'm wrong, though, and I'm not an electrician.

                          Now, here's the kicker. The power cord on the welder, which is the original Lincoln power cord, is not 6 gauge, or 8 gauge, or even 10 gauge. It's 12 gauge. You'd think that if the welder required a 50 amp circuit they would put a heavier power cord on it, wouldn't you?

                          I've never tripped the breakers, and I've used the welder at its highest settings. The welder is specified at 25 output volts. 220 volts input at the 50 amp circuit breaker rating is 11,000 watts - which at the 25 volt output level would be 440 amps. Unless I'm missing something - and as before I'm not an electrician and it's been a long time since I took physics - you won't be coming anywhere near the capacity of your 50 amp breakers or 6 gauge wire.

                          John

                          Comment


                          • #14
                            Originally posted by JohnMartin View Post
                            It's 12 gauge. You'd think that if the welder required a 50 amp circuit they would put a heavier power cord on it, wouldn't you?

                            I've never tripped the breakers, and I've used the welder at its highest settings. The welder is specified at 25 output volts. 220 volts input at the 50 amp circuit breaker rating is 11,000 watts - which at the 25 volt output level would be 440 amps. Unless I'm missing something - and as before I'm not an electrician and it's been a long time since I took physics - you won't be coming anywhere near the capacity of your 50 amp breakers or 6 gauge wire.

                            John
                            Yeah, I'd think that they would use a larger wire for the power cord. Since it's short, the voltage drop is small. They probably use a high temperature insulation to match the heat generated by the wire when the welder is used at the rated duty cycle.

                            The transformers are huge, and are not super efficient. Given 11K watts in 5K watts out tends to indicate that the magnetic field does not reach across more than 50% of all the coils as it expands and collapses. ( based on what little I remember from high school physics)

                            The inverter based machines are much more efficient, some close to 90%

                            Dan
                            At the end of the project, there is a profound difference between spare parts and left over parts.

                            Location: SF East Bay.

                            Comment


                            • #15
                              Originally posted by JohnMartin View Post
                              Now, here's the kicker. The power cord on the welder, which is the original Lincoln power cord, is not 6 gauge, or 8 gauge, or even 10 gauge. It's 12 gauge. You'd think that if the welder required a 50 amp circuit they would put a heavier power cord on it, wouldn't you?
                              Not unusual. It is all about voltage drop (not much in a short wire), and the fact that the power cord isn't buried in the wall, so the heat will dissipate fast.

                              that being said you can get some nice 8/3 SOOW wire that will easily fit in a standard 50 amp plug if you are worried about it. Pretty large diameter. I have a cord made up of that stuff for my backup generator cord for my house.
                              Last edited by tmarks11; 02-02-2015, 11:00 PM.

                              Comment

                              Working...
                              X