i want to know more about electrical installation works.

This link has been removed as there is no content on the page, only contact information

Its a commercial electrical contractor's website.

IFI is an international forum no one here will have any clue as to their qualifications. Ask local people they have worked for in the past.

Since we do not allow advertising here, the link you posted is borderline, for anything other than asking for recommendations about their work.

IFI staff

Edited June 14, 200817 yr by mod07

My Lincoln 225 amp tombstone is over 30 years old. Can't say about the core but it does in fact have a cooling fan. I used to run it on a 220v dryer circuit (30 amp?) I have since installed a dedicated 50 amp breaker for my shop. Since I no longer have to run 120 feet of extension cable to the dryer outlet, I believe the welder actually performs better not to mention the added safety:)

Steve, isn't it true that a circuit can be derated, per code, when it's a dedicated circuit for a low-duty cycle appliance like a welder?

I use a 10 gauge 100' extension cord with my TIG sometimes. Drawing as much as 50 amps, but in short spurts with breaks in between. The welder has a 20% duty cycle at max output, so it's only even possible to draw 50 amps for 2 minutes out of every 10. 2 minutes of arc time out of 10 doesn't sound like much, but I've NEVER had the welder shut off due to duty cycle. I've checked the cord after doing alot of welding and it has never even been warm.

Yes, BUt you may have misunderstood the meaning of that term.

De-rating a circuit is done many times. But de-rating is for the total load of a panel, NOT the individual line, a breaker (fuse, etc) is there to protect the wiring from over load. An example is a 8 unit building, each unit may have a 100 amp panel, but the building set up may allow you to de-rate that to a 400 amp main panel to service the entire building, as when the units are offices, they may have 100 amp sub panels. but never need that much. it does NOT mean to use smaller wires. a 100 amp panel needs 100 amp wire, a 400 amp needs 400 amp wire. 50 amp welder plug needs a 50 amp wire and breaker, IF you have 10 gauge then its 30 amp. putting a 50 amp breaker on a 30 amp line, is removing the stated protection, and can cause you or your kid, friends, etc, to DIE.

A laundry have have 20 circuits for 30 amp dryers. While each circuit is still a 30 amp breaker, the main panel can does not need to have 600 amps. due to de-rating it can be less than a 600 amp panel, because it should never need that much. But each 30 amp line, must still be protected by a 30 amp breaker if they are wired with 10 gauge THHN wire. Just as 50 amp breakers should have at least 8 gauge THHN wiring.

Any more info and I will have to charge you :)

Anyone who knows of a reliable electrician in San Diego?

This link has been removed as there is no content on the page, only contact information

Yes, BUt you may have misunderstood the meaning of that term.

De-rating a circuit is done many times. But de-rating is for the total load of a panel, NOT the individual line, a breaker (fuse, etc) is there to protect the wiring from over load. An example is a 8 unit building, each unit may have a 100 amp panel, but the building set up may allow you to de-rate that to a 400 amp main panel to service the entire building, as when the units are offices, they may have 100 amp sub panels. but never need that much. it does NOT mean to use smaller wires. a 100 amp panel needs 100 amp wire, a 400 amp needs 400 amp wire. 50 amp welder plug needs a 50 amp wire and breaker, IF you have 10 gauge then its 30 amp. putting a 50 amp breaker on a 30 amp line, is removing the stated protection, and can cause you or your kid, friends, etc, to DIE.

A laundry have have 20 circuits for 30 amp dryers. While each circuit is still a 30 amp breaker, the main panel can does not need to have 600 amps. due to de-rating it can be less than a 600 amp panel, because it should never need that much. But each 30 amp line, must still be protected by a 30 amp breaker if they are wired with 10 gauge THHN wire. Just as 50 amp breakers should have at least 8 gauge THHN wiring.

Any more info and I will have to charge you

HI STEVE; What does THHN. Mean ??..... Norm ::)

Its the type of insulation that is covering the wire conductor itself. Specifically THHN is a Heat resistant Thermoplastic, that comes with an outer covering of a nylon jacket it its equivalent.

This is rated for use in areas not exceeding a temperature of 90C/194F in dry or damp locations. it is either installed in a conduit, or in some conditions supplied already inside of another plastic type covering known as Romex.