We sit in Witbank this morning with a varying supply of around 170v.

This is the 3rd time in a week this has happened - a sign of the season?

Feedback is that it is an Eskom problem.

I’ve set my Sunsynk for a min - max volt supply. But this was not a factor then.

Any advice or comments will be welcome.

4 hours ago, Johandup said:

We sit in Witbank this morning with a varying supply of around 170v.

This is the 3rd time in a week this has happened - a sign of the season?

Feedback is that it is an Eskom problem.

I’ve set my Sunsynk for a min - max volt supply. But this was not a factor then.

Any advice or comments will be welcome.

Quite disapointing that this is happening. How often does this occur and for how long? 

If it is just a few hours per day I would leave it and let the inverter disconnect. No use having power in my house if my electronics wont run properly! It is quite problematic though. 

I am amazed at how the Eskom voltage and grid frequency change constantly, the voltage varies between 222 volts and 238 volts, the grid frequency between 48 and 52 hz. My Microcare Bi-inverter kept the voltage constant on the supply to my household equipment. I find the Kodak OG 7.2 has its voltage bounce up and down as the Eskom power does. The only time the Kodak inverter supplies clean constant power is when the inverter is in PV and battery mode only with Eskom off line.

With my previous Infinisolar 4kw hybrid the output was kept to a constant figure.

With the current 8kw Sunsynk the output varies and is not kept to the set figure.

I don’t mind as it is within acceptable parameters - would be interesting to see what it does when I switch the incoming power off.

Edited December 22, 20213 yr by Johandup

On 2021/12/21 at 7:39 AM, Venom said:

I am amazed at how the Eskom voltage and grid frequency change constantly, the voltage varies between 222 volts and 238 volts, the grid frequency between 48 and 52 hz. My Microcare Bi-inverter kept the voltage constant on the supply to my household equipment. I find the Kodak OG 7.2 has its voltage bounce up and down as the Eskom power does. The only time the Kodak inverter supplies clean constant power is when the inverter is in PV and battery mode only with Eskom off line.

We had fluctuations in voltage where I live, sometimes lower than 180v. There would be intermittent low voltages whilst we had power, and ALWAYS a low voltage on restoration of power after a load shed. 

Residents only really started paying attention when they were working from home, bought UPS to keep their wi-fi connections going and found those complaining or even turning off when input voltage got too low. 

A call was made to City Power. I don't know what they did, but the situation improved. We still get fluctuations but the low now is usually about 220v. I'm told (but can't verify) that the transformer in the substation has multiple taps and they just move up or down one tap.

10 minutes ago, Bobster said:

transformer in the substation has multiple taps and they just move up or down one tap

Correct - also way to cope with overloading. 
Then  💥

To protect your equipment and force your inverter to work without Eskom, get one of these cut-off switches.

https://www.banggood.com/SINOTIMER-SVP-917-63A-80A-Din-Rail-Adjustable-Over-Under-Voltage-Protective-Device-Current-Limit-Protection-Voltmeter-Ammeter-Kwh-p-1817221.html?cur_warehouse=CN&ID=6289907

 

6 minutes ago, TimCam said:

To protect your equipment and force your inverter to work without Eskom, get one of these cut-off switches.

https://www.banggood.com/SINOTIMER-SVP-917-63A-80A-Din-Rail-Adjustable-Over-Under-Voltage-Protective-Device-Current-Limit-Protection-Voltmeter-Ammeter-Kwh-p-1817221.html?cur_warehouse=CN&ID=6289907

 

Is this legal for use in South Africa? I mean, if it's not SANS certified, can you legally use it in your DB? Would it pass proper COC?

CE approved, so should be OK.

Other option is to install a contactor on supply with a voltage over/under relay protection.