good one!After replacing the Torch plug and putting in oil and fuel, I was able to capture some waveforms from my new Wen 56225i inverter. First, the inverter:
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Once you remove the side panel, everything seems fairly easy to get to. It started up without incident and ran very smoothly. I got my DMM out and the inverter tested at 124.5 VAC, identical to my GN400i. Just like with the 400i, I could not lock onto a Hz reading. It jumped all over the place. It's probably a DMM issue. Next was the scope.
Power output was not very smooth at first. It was jumpy and a bit jagged:
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I discovered that this Wen has the same issue as the Champion. You have to use the neutral bonding plug. For some reason, that cleans up the signal on the scope. Notice the Hz reading. That will become relevant later.
I was still getting weird readings, even after using the neutral bonding plug. The display was a bit erratic and jumped around. Plus, the Hz readings kept jumping up and down. That was strange. I hadn't seen that before when testing my other generators, even the non-inverter ones. There was some noise in the signal as well, which was also out of place.
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I caught it on one of the frequent Hz bursts to above 80 Hz.
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I was a bit perplexed. The other inverters I have don't do that. Hz is always stable, as is VAC. I started brainstorming to try to figure out what was going on. Why was I getting such anomalous readings from this inverter?
I had to run a fairly long power cable from the scope to the wall outlet in the garage. I noticed that the power strip I was using that was connected to wall power looked old. It was yellowed and very worn looking. I wondered if I might be having issues because of that. I removed the old power strip and replaced it with a known-good APC one. After that, the signal seemed to clear up considerably.
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The Hz stopped jumping up and down as well. It remained stable at 60 Hz, as you would expect.
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Apparently, from what I saw, the old power strip I was using to power the scope was causing strange readings from the inverter. I'm not sure how that would happen, but once I removed the old strip from the power chain, the readings cleared up and the inverter readings became what you'd see from any other inverter. VAC is off, but that appears to be because my cursors are not set correctly. I did confirm the inverter is outputting 124.5 VAC, though.
I pulled the old power strip out of my rotation since it seems to be causing issues. My takeaway is to make sure the scope is getting clean power from the wall or readings might be wonky.
also does the apc strip have any protection like surge or filtering?
yea any coils or wire loops affect the readout.
and can pick up rf trash as well...
so did you use the old strip when checking the other gens as well???
you might have to revisit those posts with updated screen shots..
it still has a couple of little spurs of trash. not much but you could see a bad firing gate or a rotor slot slight out of time.