Sunday, 21 October 2018


Just a brief comment on the last post expressing my thanks to all those readers who left sympathy comments regarding the overalls.  As for the other readers who left comments.  Well I don’t know what to make of people who can laugh at someone else’s misfortune Winking smile

Does anyone know a tall stout man in need of some new overalls?

Today its been sunny…. no raining.. .actually sunny….. don’t you recognise rain.  I guess you might describe today as a bit of a wash out, meaning I can’t work on the trailer modifications.  Actually the teeth on bit of the hole saw are now too blunt to cut through the metal sides of the boxes on the trailer.  Work has come to a halt.

Looking for something to do I checked on the solar panel output for October.

solar power

It’s been averaging between 12 and 34kWh per day.  We should be generating more and I think I know the reason why this isn’t happening.

Last October (2017) our average daily daylight consumption was between 3 and 5kWh.  This means we should be generating a surplus to feed back into the grid.

elect usage

I’ve found some more solar output data on the software application and have identified why we aren’t getting maximum output.  The problem is the electrical utility company is supplying too higher voltage.  Consequentially in times of peak sunlight the house solar inverter can’t ‘push’ surplus back into the network.  The inverter must comply with the relevant Aust/NZ regulations when it comes to maximum voltage AND SO SHOULD THE UTILITY COMPANY.  But they are not!!!!!  I’ve lodged a complaint and am now waiting on them to either fit monitoring equipment to the house or reduce their voltage to the required maximum level.  I’m also thinking this excessively high voltage might be the reason why the TV failed.

Hopefully tomorrow will be dry and I can return to working on the trailer.


Catherine VK4GH said...

How did you work out the electricity co is outputting the power at too higher voltage?

Tom and Jan said...

Two ways Catherine

1. The Inverter emails me a fault message when it has to shut down because the grid voltage is too high.
2. I used my multimeter to check the main supply voltage which I have recorded as over 258V

Paul (from Waterway Routes) said...

Perhaps the supply voltage is being pushed up by too many people with solar power using high voltages to feed their excess electricity into the grid.

Tom and Jan said...

Paul I'm told that can't happen as the inverters all have a maximum voltage output which has to be below the "legal" maximum grid voltage.

Paul (from Waterway Routes) said...

I thought it was a recognised problem that solar panel installation companies "accidentally" set their peak voltage too high to ensure their customers always supplied the grid without turning off so their customer saw the wildly high benefits claimed in the sales literature.

Do the over-voltage trips occur at times of high sunshine?

Tom and Jan said...


I suspect some solar salesmen don't known nearly as much about the system and technology as they profess. One salesman told me we could have an AC battery!

The problem is the AS/NZ standard for maximum voltage. The utility company is allowed to increase the standard 240V to 254.4V. Solar systems are allowed another couple of volts over that. However there has been a large adoption of residential solar here in Perth and I suspect some solar installer increase the system output even higher to ensure "their" customer gets maximum output. From what the utility technician was telling me I gained the impression the utility company isn't checking voltage levels and only responds to complaints. In our case the technician transferred us to another phase which had a lower voltage.