Energy Saver for Old Welding Sets

Old Welding sets consumes significant power, in the tune of 3 kWh to 10 kWh, in idle condition (when no welding is going on but the welding machine is kept energized). This is the reason that I am very much egger to use the energy saver kit on my both machines. Welding generator set consumes 9.5 kWh when running idle and other machine which is welding rectifier set consumes 2.9 kWh when running idle.

OK, so why not just switch the thing off when it is not in use?

It is not always possible to switch off the machine manually.

Distance between welding spot and machine varies from 20 meter to 200 meter. Distance, height and mind set of the Welder are main reasons.

200m is a piece of cake for RF remote. Anyway, for your existing auto system. If you are trying to sense the voltage drop at electrode touching on a motor welder with just temporarily unenergised exciter, while output is connected to a second small power supply, this is NOT possible, simply because the second power supply you use will NOT raise the voltage at all, it practically sees a short-circuit on the machine side (and is possibly overloaded). You MUST use other ways to sense electrode touching. I would for example settle for something like 1%-2% of normal exciting current at off-time, (that would give you significant economy) and use the relatively small output voltage value for deciding when to start-reset timer etc and get rid of the second power supply (or use it just for the small exciting current, depending on machine specifics, it may be necessary for that). Provision should also be made for the output voltage time curve because of core self-magnetism progressive loss the first seconds exciter is "de-energised". Now, if welder output can be disconnected using a massive relay etc, it CAN easily be done differently. S.M.

Please confirm your units.

kWh is an energy unit not a power unit.

I'd use manual wired or wireless remote control. Wouldn't rely on auto shut off for economy (or anything). S.M.

A mains contactor actuated by a foot switch by the welder might solve the problem.