JHB voltage drop

J

Jladan

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Anyone else notice JHB voltage is currently dropping especially during peaks to around 190 - 200?

If it is being widely observed what could be the cause ? Us just not getting enough juice from Eskom ?
 
Jladan said:
Anyone else notice JHB voltage is currently dropping especially during peaks to around 190 - 200?

If it is being widely observed what could be the cause ? Us just not getting enough juice from Eskom ?
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Nope most places are between 217 to 240 that I know of, sounds like your area is overloaded.
 
Your local sub is overloaded. I've been getting between 209 and 213 volts the last couple of weeks. Normally pick it up in the morning when I have to put the toast back in for a second time.
 
Mike Angelo said:
Your local sub is overloaded. I've been getting between 209 and 213 volts the last couple of weeks. Normally pick it up in the morning when I have to put the toast back in for a second time.
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Shoo I've only seen mine drop to 219, on average it's around 230
 
Massive issue in our buidling, but its local to the buidling

Dropping to 170 last I checked, lights sometimes pretty much go off its so bad, you cant cook or use the microwave when this happens, the microwave just tunes you hommmmmmmmmmmnnnnnnnope.
 
Pixies said:
It's likely suburb specific or even block specific in some cases.
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Normally is, voltage drops are indicative of load, voltage increases are oversupply... We know that last option won't really happen in SA :-)
 
Well I’ve got nice graphs showing the dip so will send onto councillor and see if anything happens
 
Geoff.D said:
And do your graphs show how the frequency varies as well?
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Frequency is a function of the source (ie grid), not the load or any peripherals in between. It hovers around 50Hz and does deviate a little though, as the grid compensates for demand
 
Geoff.D said:
And do your graphs show how the frequency varies as well?
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Back in Feb ours was jumping between 49.8 Hz on the low side and 51.2 Hz on the high side, fluctuating multiple times per second. At the same time, voltage down at around 187v. Two days ago, stable but down at 180v / 49.7 Hz. At the moment, stable 226v / 49.9 Hz.
 
gbyleveldt said:
Frequency is a function of the source (ie grid), not the load or any peripherals in between. It hovers around 50Hz and does deviate a little though, as the grid compensates for demand
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Not really the case, as it is a function of generation, distribution and load.

The limits used to be 50 +/- 0.5 Hz. Currently, the upper limit has been changed to +1.5 Hz according to some sources.
 
[XC] Oj101 said:
Back in Feb ours was jumping between 49.8 Hz on the low side and 51.2 Hz on the high side, fluctuating multiple times per second. At the same time, voltage down at around 187v. Two days ago, stable but down at 180v / 49.7 Hz. At the moment, stable 226v / 49.9 Hz.
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touche! Enough said :D
 
Geoff.D said:
Not really the case, as it is a function of generation, distribution and load.

The limits used to be 50 +/- 0.5 Hz. Currently, the upper limit has been changed to +1.5 Hz according to some sources.
Click to expand...
That makes sense. I read at the time (can't find the source now) that a power station should auto shut-off at 49.4 or 50.6 Hz and wondered how we were still on.
 
Please change scale between 240 and 160 , this should eliminate loadsheding drops .
Don't think they will be able to bump up the voltage at the transformer.
Would be nice to compare neighbors too.

These low voltages will destroy your fridge motor, suggest you buy a fridge safe from ellies
 
Easy solution is for them to approve grid tie inverters with export and the volts will pickup when the sun shines.
 
1653487441002.png
Sunday was bad but we seem to getting better:
1653488204629.png

Edit: Can clearly see the evening peaks & LS stuffing around.
 
Last edited:
Geoff.D said:
Not really the case, as it is a function of generation, distribution and load.

The limits used to be 50 +/- 0.5 Hz. Currently, the upper limit has been changed to +1.5 Hz according to some sources.
Click to expand...
Distribution and load cannot affect frequency. It is purely a function of generation. The frequency may shift a little but everything after generation cannot affect it without serious distortion causing things to blow up. It’s for this reason that generation units take a while to connect to the grid, because it needs to synchronise with all other generation units.
 
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