need help getting right size breaker and wire for tig welder

jss12

I have a lincoln pro 175 tig welder
(230v)

my I like to know what size wire and breaker this unit needs. I really dont understand the info in manual

http://im1.shutterfly.com/media/47a0...D550/ry%3D400/

I need to run about 30 ft of wire..

frenchelectrican

Will this unit will be at the detached or attached garage ?

I did read it and it stated it need 100 amp breaker with 10mm² { #8 AWG } conductor size but I don't think that is correct at all.

Before we can go on further in if you have detached garage how big the subpanel you have there or what ??

If attached garage it will be not too bad to deal with it.

Merci.
Marc

a7ecorsair

At the bottom of the referenced chart there is a foot note:
The National Electrical Code permits operation at rated output and duty cycle from a 50 amp receptacle when supply lines and fuses are sized per this table.

I suppose the duty cycle allows the use of smaller wire.

jss12

the workshop is not part of the house. i think main breaker switch in panel is 100.

frenchelectrican

Ok as you say the workshop is not part of the house so it is a detached building and per the code we can only allowed one MWBC so if you have exsting circuit going to the workshop can you tell us what size circuit you have in there ??

And to increase the capaitcy of that circuit you have to install the subpanel and use the correct conductor size for it.

Merci.
Marc

kbsparky

Sounds right to me. Notice that the wire must be installed in conduit for that size to be utilized.

__________________
-KB

Life is uncertain -- eat dessert first!!
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

jss12

100 amp sounds huge not to mention 100 amp and only a 10 gauge wire? that does not sound right

the machine uses a 50 amp male plug.

50 amp plug if i remember reading right should be match with a 8 gauge wire.

oleguy74

look at art.630.11 in the nec.his tig has a duty cycle of 25%.multiply rated input current by the factor gor 30% duty cycle factor which is .55.you come up with 35.75 amps.#8 is fine.art 630 in nec deals wiyh welders.see table 630.11(a)

frenchelectrican

Thanks for bring it up and almost slipped from my mind due I am got used with French codes and of course that is only with hardwired but for cord /plug set up I am pretty sure that the bet is off on this one.

Merci.
Marc

jss12

lincoln just replied saying I need 8gauge wire and 125 amp breaker.

this once again makes no sense to me

unit has a 50 amp rate plug on it

the breaker is suppose to protect wire

kbsparky

Why not? You have to stop thinking inside the box on such installations, and follow the Code.

Section 240-4(D) does not apply here.

You are under 240-4(G), and that section refers to article 630. There are specific guidelines for welder circuits, and they have already been pointed out to you. The manufacturer has also confirmed their circuit chart is correct.

Just be sure that your #8 wire is installed in conduit.

Table 310-16 shows that #8 THHN wire is capable of carrying 50 Amps. Same size as your receptacle and cord and plug on the welder, BTW. Multiply that by 3 and your max breaker size could be as high as 150 Amps. Since the manufacturer has already done the other duty-cycle calculations for this unit, they have determined that a 125 Amp breaker is sufficient.

__________________
-KB

Life is uncertain -- eat dessert first!!
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

jss12

my total main breaker is 100 so dont think i can run this machine if it needs 125 just for the 1 machine