I guess the easiest way to check the voltage is with a volt meter on the leads while someone pulls the trigger. The wire speed can be obtained by holding the trigger for a length of time and multiplying it out to obtain IPM. As far as the voltage and wire speed you mentioned here is what I have from Lincoln. 24Ga-1/4" thick plate, 15-20 volts, WFS 100-200 IPM, Gas 25-35 CFH (Short Circuit Transfer). Many tables are listed this is just one of them. (Table 6 of the MIG/ MAG Welding Guide www.lincolnelectric.com) I hope this helps
When you say your wire feeders were recently calibrated, does that mean your volt meter on the feeder was calibrated too? or does it even have one (since some don't)? If you do have one and it was calibrated, then I would trust that meter, not the one on the power supply.
As the previous post said (I think it was Wildturkey?) the easiest way to check it is to put a voltmeter on it while someone runs a bead. One lead on the ground or wprk side and the other as close to the arc as possible on the electrode side of the circuit. Usually the terminal block on the wire feeder is sufficient.
I haven't used a CV655. Is there some type of control that you might have left "on" that gives a hot start? Probably not but I thought it was worth an ask. Otherwise, all you need to do is either turn down your voltage, or turn up your wire feed speed, or a little of both, enough to prevent burnback. And possibly the earlier post might have been using CO2 instead of an Argon / CO2 mix? Was the brand of wire he was running the same as yours?
The problem I run into when I try to give a volts/amps setting to someone is that everyone's technique is different. What I like to run may or may not work for everyone else. Even when following a WPS, some run hot and some run cold while still within parameters. So I guess, I wouldn't worry too much about sticking to 28/200. You tried it, it didn't work for you for whatever reason, so I would make adjustments (a little at a time) until it does work.
Hope this helps,
CHGuilford
Hi Mark
I think your problem here (unstable arc) has got to do with your gas - voltage combination. At 28V, you really want to be in spray transfer. The 25% CO2 will however not allow you to achieve this under normal operating conditions. I believe that you need to either get a gas with 20% CO2 or less, (85Ar/15CO2 is popular) or lower your volts and accept that you are welding in short cuircuit mode.
I am assuming that you are welding with bare wire (GMAW) and not flux core! (FCAW)
Regarding the measurement of the voltage, I always use an electronic multi-meter and connect the one pick-up to the terminal block of the wire feeder and the other pick-up against the work piece as close to the arc as practical.
Hope this helps
Regards
Niekie Jooste