View Full Version : Ocv?

01-09-2012, 11:19 AM
I appologize if this is a dumb question, but, my machine has two ranges, low and high.

the front of the machine says the high range is 55 OCV and the low range is 80 OCV.

it also says that high range is for cutting, gouging, burning holes, and vertical/overhead with 6013 only. it is a Linde 225AC

Does the higher OCV make welding easier/better in some way? I'd like to be able to use the machine to the best of my abilities.

thanks for any input,

01-09-2012, 11:33 AM
Hello Meborder, the short answer is that higher OCV's makes arc starting easier and sometimes helps with keeping the arc from extinguishing when you are varying your arc length in a radical manner. Best regards, Allan

01-09-2012, 12:19 PM
OCV should stand for Open Circuit Voltage. Per Nema I believe the maximum allowable is 80 Open Circuit Volts. The more the voltage the easier it is to start the arc on the older machines. The new inverters have an open circuit voltage of between 9 - 13 volts but still start great.

Rick V
01-09-2012, 12:48 PM
There were a number of almost identical welders sold under the names of Century, Canadian Tire, Sears, Montgomery Ward, etc. that sported both a high and low output jack. Here's the explanation from the user manual for the Century model 110-114.

Most ac welding operations will be performed using the LOW AMPERAGE jack because it has a higher open circuit voltage (OCV), provides a deep penetrating arc for welding rusty or thicker metals. American Welding Society (AWS) rated rods 6011 and 7018 type are formulated to work well with the higher OCV of the LOW AMPERAGE jack. LOW/180 amp. jack = Approx. 71.6 OCV

The HIGH AMPERAGE jack is better suited for welding thinner pieces because the OCV at this tap is much lower. This tap delivers a shallow penetrating arc and smooth, non-stick welding, preferred for welding thinner metals. AWS rated 6013 and 7014 type rods work well at this tap, since they do not require a very high open circuit voltage to start. HIGH/230 amp. jack = Approx. 44.7 OCV

There you have it... straight from the manufacturer.

01-09-2012, 02:01 PM
wow! talk about counterintuitive ... to use the high tap for thinner metals and low tap for thicker metals.

it does jive with my perception, however. the 7014 did seem to run better on the high tap, and seemed easier to control.

i'm going to try some sheet metal repair here soon (5/64 6013), so it is good to know which tap to use ... i'd have screwed that up :)

thanks again for the help!

Rick V
01-09-2012, 03:54 PM
... so it is good to know which tap to use ... i'd have screwed that up :)
That's what the manual said... but it would be better to get a feel for the difference. I'd try running some praqctice beads using both jacks - adjusting for the same indicated amperage. Go with what you like best.
It's nice to have that choice - between a punchy arc and a soft arc. I didn't know about this (no manual) for a long while. Have fun!

01-09-2012, 05:06 PM
I can't seem to make any sense of that "snippet" from the mfg. The OCV is irrelevant to the characteristics of the arc, as once the circuit is closed (arc is struck) the machine will operate at a voltage dictated by the amperage and arc length.

Rick V
01-09-2012, 07:06 PM
Hey sn0border88, Yes it's a mite confusing for sure. :confused:

Yes, what really matters is 'Arc Volts' not so much Open Circuit Voltage (OCV).
Some examples:
My Linde 250 AC/DC claims 30 arc volts and an OCV of 78 volts.
My Lincoln AC/DC 225/125 claims 25 arc volts and an OCV of 79 volts.
My CTC inverter (80 amps) claims 21 arc volts and an OCV of 80 volts.
Note the OCVs are almost identical but the arc volts are quite different.

How do they weld?
The Linde has a puchy, penetrating arc.
The Lincoln has a 'normal' arc.
The CTC Inverter has a 'soft' arc.

All thse machines can draw a pretty long arc - a partial measure of OCV. High OCV helps to maintain the arc when your arc gap gets too long but is rather useless for welding - that is laying down metal. None of these welders can pull the 3 to 4 inch arc length that one can draw from a Lincoln V350pro! But what good is that - for painting light pictures in the air? Still, it could save you a restart.

I had a 115 volt transformer welder that had a 64 volt OCV but only put out 60 amps. It could draw a long arc that was great for using a carbon arc torch - a pair of carbon rods to maintain an arc flame for heating. I kept removing wire turns from the transformer secondardy winding, steadily raising the welding current (but lowering the arc voltage and OCV). I got the machine to put out about 90 amps but... there was no longer enough arc or OCV to run that carbon-arc torch and when welding I had to maintain a short-arc else the arc went out. :realmad:

In the end, I think what counts is 'arc volts'.

For the machine under discussion, I've looked inside and the LOW and HIGH jacks are just the different taps off the same transformer secondary winding, one having more voltage but less amperage than the other jack... kind of like that old 117 volt welder of mine.

I hope that helps somewhat... :blush:

David R
01-09-2012, 08:26 PM
They used to call it slope. Now its called arc force in stick.

Buttery smooth for 7018

"Crisp" for 6010.

6013 DCEN Crisp works best for me. I almost never use 6013, but after a bunch experimenting with a few welders, this is what I came up with.

Over head and vertical up freeze faster on Crisp which makes it easier to weld no matter what rod
I am using.

My V350 is 60 OCV unless I turn the arc force to over 9 then it goes up to 70 OCV for gouging.
I found this out the hard way and had to call lincoln because it was NOT in the manual.

Buttery smooth for nice looking beads of 7018 on the flat. Self peeling slag, flat smooth beads with fine lines in them. I can run more amps and shorter arc in this mode.

I have no AC welder now. I have seen the HI and LO taps on welders and used them. At the time I had no idea the difference.

Run both and see the difference for your self. Get to know the machine.