Idling power consumption on transformer TIG machines?

T

ttyR2

Plastic

Joined

Dec 9, 2007

Location

Athena, OR

• Feb 23, 2008

• #1

On transformer machines such as the older Lincoln IdealARC TIG 300/300, do they draw a large amount of current when powered on but idling without an arc being struck? I'm confused with the PFC setup that some machines have.

I'm shopping around for a good used machine, but if the older transformer machines use a lot of power when not welding, it's inverter time.

 

tnmgcarbide

Diamond

Joined

Jul 6, 2004

Location

N. GA- 33.992N , -83.72W usa

• Feb 23, 2008

• #2

i never did any experiments, but my machine has popped the (undersized , worn) panel
breaker powering up -when the controls were on high(275A) and the current control at 70% , left in that position . now i always turn the current down before i turn it on
and it hasn't happened since.

although , when under load , i've never had the (60A )breaker pop . it may be that the
old relays are arcing at powerup on my 1984 tig250/250 .

my assumption would be that there shouldn't be any more than a couple amps draw for
running the fan and solenoids and pilot lamp ,until the arc is struck.

i'm interested to know if anyone's ever put an ammeter on one to find out.

 

S

SBAER

Hot Rolled

Joined

Aug 21, 2006

Location

Kitchener, on canada

• Feb 24, 2008

• #3

I have the exact same welder and have taken current measurements out of curiosity. Mine draws about 30A at idle, the current draw actually decreases when you start to weld. I have 40A breaker on it now and have no problems welding up to about 175A. If you are going to have the thing on all day long it will cost a fortune.

 

macona

Diamond

Joined

Jun 20, 2006

Location

Beaverton, OR

• Feb 25, 2008

• #4

You can lower the idle current significantly by installing power factor correcting capacitors.

 

A

Avanti

Cast Iron

Joined

Nov 13, 2003

Location

Wauna, WA

• Feb 25, 2008

• #5

How would one go about doing that?

 

macona

Diamond

Joined

Jun 20, 2006

Location

Beaverton, OR

• Feb 25, 2008

• #6

Easiest way is to see if there is a version of your welder that has PFC and order the same parts. One could also look at and equivalent machine that has them and order the same caps.

 

Jim Shaper

Stainless

Joined

Nov 5, 2007

Location

Minneapolis

• Feb 26, 2008

• #7

macona said:

You can lower the idle current significantly by installing power factor correcting capacitors.

Click to expand...

Macona, you're backwards in that assertion. PF correction caps could be the reason his idle current is so high. Look at the table on page 13 for the Syncrowave 250/350's and you'll see that idle current jumps from 2.8A to 49.5A when you add PF caps.

http://www.millerwelds.com/om/o363f_mil.pdf

 

macona

Diamond

Joined

Jun 20, 2006

Location

Beaverton, OR

• Feb 26, 2008

• #8

Looks like I got that one backards. I could have sworn it was the other way around. Drops the power draw under load.

Another benefit of PFC is it will increase the duty cycle when using unbalanced AC out according to the ESAB manuals.

 

Jim Shaper

Stainless

Joined

Nov 5, 2007

Location

Minneapolis

• Feb 26, 2008

• #9

It does drop the power draw under load, but it raises it considerably at idle.

From my limited knowledge of PFC, it's useful to reduce the consumption when the machines aren't idle very much. For a small fab shop or single operator, it would eat you alive in electric bills, but put it on a robot welder and it saves you money.

 

B

Benesesso

Hot Rolled

Joined

Jan 20, 2006

Location

Phoenix, Arizona

• Feb 26, 2008

• #10

From some other discussions on this forum, it seems that while the idle amps (current) may be high, it's "out of phase/sync" with the voltage, so the power (watts) is quite low.