Just wanna share my experience in case someone encounters similar situation.
On my remote off-grid property, we have been doing lots of stick welding lately.
I have 6 x Pylontech US3000C batteries.
Originally I had Multi RS Solar - single tracker version with 3,6 kW of solar + another 6,3kW of solar on separate MPPT RS.
There is about 350W base load 24/7.
When welding, the inverter would often overload and shut everything down. Peak AC load according to VRM is around 2800W, but I guess the Multi RS cannot handle the starting current or something.
So I have replaced the Multi RS with MultiPlus-II 48/3000.
Now it works just fine… not a single overload so far…
So PSA for the community … do not weld on Multi RS, it doesn’t work well. Especially if running some other essential loads, like in my case - networking equipment - which can be damaged with frequent shutdowns due to inverter overloads.
That’s interesting.
I have been running my welder for quite a while with my Multi RS single tracker. No problems to report. This Multi RS is also running the home at the same time including networking equipment and a 2U server.
The one difference is that I’m TIG welding rather than MMA like you are. Perhaps a stable TIG arc is not as harsh as intermittent MMA arcs.
I have also used my TIG welder on a 24/3000 MultiPlus with no issues either.
At first, I installed 48/2000 just for the essential loads when we realized it doesn’t work. So the welding wouldn’t mess with my networking gear. But I wasn’t happy with the result because suddenly the VE.Bus inverter took over in Venus and whatever was happening on the Multi RS wasn’t counted into the total consumption. I guess VE.Bus inverter has priority over VE.Can inverter in Venus.
Then an opportunity arose to sell the Multi RS, but 48/2000 wasn’t enough to power the peak loads at the property.
Luckily in my other home which is on-grid I had 48/3000, so I swapped them. It’s on-grid so 2000VA it’s fine plus there is only 50Ah battery anyway.
Yesterday my friend came to do some welding for the first time since I swapped the inverters and got rid of the Multi RS. I told him to stop immediately if the power cuts out and give me a call, but he has been welding 2nd day straight without a hiccup so far.
Also similar story as @wkirby said… I sold MultiPlus-II 24/3000 to a client who also welds and he had no issues to date, except he melted the fuse holder once… but we since doubled the cables. So that’s why I was bit surprised when I found out I wan’t able to weld on Multi RS.
Interesting. Yeah… cheap MMA welder here. When the skies were completely clear, we would get less overloads as the power output on Multi RS is also dependent on the sun. But it would still overload here and there. We also tried plugging in Honda EU20i 2kVA generator on the AC input of the RS but the current would first overload the generator and the RS would disconnect and overload itself.
What is the welding current? Is the welder using inverter technology? Or is a simple one with transformer? If it’s a simple one, then initially, when touching the stick to the welding surface, it is creating a short. And RS is reacting very fast. Please correctly describe the setup, so other users are receiving the full info.
