Is this normal or must I start running...

I maintain that anything more than 245VAC is too high.
Does it not have an overvoltage protection setting?
 
I take it you're posting from your mobile 5km away by now... :ROFL:






more seriously, I would hope that a decent inverter will have overvoltage protection and either shut down or pop a fuse
 
swakop_toe said:
I maintain that anything more than 245VAC is too high.
Does it not have an overvoltage protection setting?
Click to expand...

The acceptable grid levels are 230 +/- 10%. Anything up to 253 V is thus within the allowed range. My inverter (Victron) often disconnects the grid due to overvoltage. I've seen voltages close to 260 V coming from Eskom.
 
Not normal in first-world countries. But it's what you should expect and plan for from our grid.
 
Tacet said:
The acceptable grid levels are 230 +/- 10%. Anything up to 253 V is thus within the allowed range. My inverter (Victron) often disconnects the grid due to overvoltage. I've seen voltages close to 260 V coming from Eskom.
Click to expand...
Yeah me too. Crazy voltages coming in at times.
 
W@P said:
Not normal in first-world countries. But it's what you should expect and plan for from our grid.
Click to expand...
Voltages are normally an issue on the local grid, not the national grid. This is probably overload on his local sub station. I know just down the road the guys are sitting at 130v due to issues.
 
Lupus said:
Voltages are normally an issue on the local grid, not the national grid. This is probably overload on his local sub station. I know just down the road the guys are sitting at 130v due to issues.
Click to expand...
Ja was referring to local infrastructure that is dodgy as hell.
 
The manual says it has over and under voltage protection and should be able to take an input of 280. I hear the ding clicking away occasionally, like a relay operating.

Upstairs I have some Gizzu mini UPSs connect to my SD-WAN, ONTS, and access points. There I have one of these on the plug: https://www.takealot.com/clearline-...ct-4-4-lightning-surge-protector/PLID34173191

I think I'll install one downstairs as well!
 
Tacet said:
The acceptable grid levels are 230 +/- 10%. Anything up to 253 V is thus within the allowed range. My inverter (Victron) often disconnects the grid due to overvoltage. I've seen voltages close to 260 V coming from Eskom.
Click to expand...
Yea i wonder if some infrastructure is set to high voltages to deal with the voltage dip just after shedding ends

ie higher voltage also means less amps on infrastructure
 
Lupus said:
Voltages are normally an issue on the local grid, not the national grid. This is probably overload on his local sub station. I know just down the road the guys are sitting at 130v due to issues.
Click to expand...
Too many guys with solar spinning their meters backwards? On second thought, that should affect frequency?
 
wingnut771 said:
Too many guys with solar spinning their meters backwards? On second thought, that should affect frequency?
Click to expand...
Yeah that would be frequency going up. Higher demand in theory should make voltage increase, but also the frequency drop.
Though it's probably a wonky transformer
 
Lupus said:
Voltages are normally an issue on the local grid, not the national grid. This is probably overload on his local sub station. I know just down the road the guys are sitting at 130v due to issues.
Click to expand...


Re voltage going too high/low:
That is usually a transformer issue (on the local grid, as you said). The fix is usually to change the number of windings - but I'm pretty sure that it is not really high on the priority list of any municipality.

leon.davibe said:
Yea i wonder if some infrastructure is set to high voltages to deal with the voltage dip just after shedding ends

ie higher voltage also means less amps on infrastructure
Click to expand...

I honestly doubt that they do it on purpose. I've also seen voltages going too low in the same municipality, so I suspect that it is simply them struggling to maintain everything. One issue I've encountered is where they replace stolen copper cables with aluminium without increasing the cable thickness. Due to the increased resistance of the cable, the customers at the end of the line had under-voltage. Increasing the voltage by changing the transformer windings would fix it for the customers at the far end of the aluminium cable, but the customers close to the transformer would now have over-voltage. The correct fix was thicker aluminium cable to start with, but the maintenance team wasn't clued up enough for that. Which makes me dread the long-term effects of bimetal corrosion, and connectors loosening due to unequal copper/alu expansion with thermal cycling.

Lupus said:
Yeah that would be frequency going up. Higher demand in theory should make voltage increase, but also the frequency drop.
Though it's probably a wonky transformer
Click to expand...

The frequency specs on the grid are much more strict than the voltage levels. Typically, the frequency of the grid should be: 49.5 < f < 50.5 Hz for all credible single contingency losses (meaning that if a Koeberg unit fails, the frequency should still be above 49.5 Hz. In case of multiple contingency losses, it may go as low as 49 Hz, but at the 0.5 Hz mark the grid should start automatic loadshedding to prevent damage to equipment.
 
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