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I know our power supply is 230 volts +10% -6%, so the supply is 216.2 to 253 volts. If the volts are higher or lower, then our solar panels, EV charging points, etc, should auto disconnect, this is for safety. I can't see how we are permitted to lift or drop the volts using an auto transformer to kid the solar, EV or battery charging that the supply has not gone out of spec.
This seems totally out of order to me. Other users on the supply will either be getting over or under voltage due to the auto transformer. Using the voltage optimiser to correct the voltage to current-using equipment I can understand, although I would not call what he fitted a voltage optimiser, it is a simple auto-transformer, the voltage optimiser would auto change tappings. The device did not auto change, but simply lifted the supply voltage to over the permitted 253 volts for all other users.
G99 approval I assume says we have looked at the system you're going to install, and are satisfied it will not cause the lines to be overloaded or the voltage to go out of specification. And since the solar without the auto transformer will not cause the voltage to go out of specification as it will auto close down, then OK go ahead. I am sure it does not say, we will import what ever you can produce? Or does it? As I try reading it says
But that does not mean the user can fit an auto adjusting transformer does it?
I have re-watched and it seems the solar panels were going over voltage
so there most have been a fault with the inverter. I wonder what he measured before he started, at 230 volts at the transformer to stay below 253 volts at the property, with 17 kW or 74 amps, the line - neutral loop impedance must be under 0.31Ω. If set to 240 volts, then 0.18Ω, so before installing such a massive solar array, one would look at the no load volts, and the loop impedance.
I would have thought if the loop impedance was above 0.20Ω then the job is a non starter. Even with the best auto stepping transformer more than 0.20Ω must be non starter.
Depending on cable runs, one must insure the solar auto disconnects before the PEN failure disconnects, and when producing so much power, one has to ask is a PME supply with overhead cables really the right option? Go to TT and no need for PEN failure device.
G99 approval I assume says we have looked at the system you're going to install, and are satisfied it will not cause the lines to be overloaded or the voltage to go out of specification. And since the solar without the auto transformer will not cause the voltage to go out of specification as it will auto close down, then OK go ahead. I am sure it does not say, we will import what ever you can produce? Or does it? As I try reading it says
So one would assume the reverse is also true, if not rejected you can export over 3.68kW, and you don't need to pay for the upgrade to the system, I would assume the upgrade would be that transformer will include some auto tapping so it can adjust tapping for import and export situations.
But that does not mean the user can fit an auto adjusting transformer does it?
I have re-watched and it seems the solar panels were going over voltage
I would have thought if the loop impedance was above 0.20Ω then the job is a non starter. Even with the best auto stepping transformer more than 0.20Ω must be non starter.
Depending on cable runs, one must insure the solar auto disconnects before the PEN failure disconnects, and when producing so much power, one has to ask is a PME supply with overhead cables really the right option? Go to TT and no need for PEN failure device.
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