[Question] Prepaid meter tripping

[Mlb]

My prepaid meter has been tripping for months now. I am 90% sure the problem is with the municipality supply voltage and not the prepaid meter but they insist on replacing the meter. Hear me out..

I measured the voltage during the day when no one is at home and it sits at 240v with no load. I begin to turn on high current drawing appliances including kettle, oven, etc and the voltage drops to say 225V at the main breaker. Prepaid meter does not trip.

Around 6pm when people (neigbours included) are at home the no load voltage is 220V at the main breaker (after the meter). I begin to turn on appliances and the voltage drops below 220 causing the meter to trip. I suspect the Meter has under voltage protection but the neighbour's meter does not so they don't experience outages like I do.

The municipality came out and couldn't figure out the problem. The depot (engineers) was then sent out and the solution they suggested was to replace the meter. They've sinced bypass the meter so I could have electricity but the no load voltage is 220V at 8pm on a Sunday night and when I load the circuit the voltage drops but the meter is no longer in place so there's no protection for my appliances.

The problem is clearly with the supply voltage from the municipality but they don't know what the problem is. Someone educate me with what the problem could be please. I am thinking the cable feeding my house and the neighbour's house is faulty causing a voltage or the supply is not able to provide enough current.

Thanks!

[Dave A]

They've sinced bypass the meter so I could have electricity but the no load voltage is 220V at 8pm on a Sunday night and when I load the circuit the voltage drops but the meter is no longer in place so there's no protection for my appliances.

What is the lowest voltage reading you get under load?
And confirm all these readings are at the main breaker.

[Mlb]

What is the lowest voltage reading you get under load?
And confirm all these readings are at the main breaker.

Yes, all measurements were done at the main breaker. The lowest voltage I've seen at the main breaker is 214V before the meter trips. Since the Meter is now bypassed I measure 216V. The more appliances I put on the lower the voltage drops. I once measured 220V with the main breaker OFF and the Meter tripped

[Tradie]

214 VAC is not regarded as low voltage, in this day and age, 190 VAC is not un common, especially if you are at the end of a circuit.

[Tradie]

Some might say that the volt drop is higher than it should be, from my experience, we dont even consider volt drop anymore, because the grid so unstable.

I would suggest you do a loop impedance test and verify there are no loose connection on the neutral or earth or even the live.

I found the best way to verify if the grid has a loose connection, you plug the loop impedance tester into a socket outlet, press the test button and switch on the stove, see what happens.

I had a private company contracted to the council to address "Danger notices", they sent out their best team, then another team and then another team, all they had a good chuckle because I am an idiot and have no idea what I am doing, eventually one of the team members climbed the pole, and imagine that, there was a loose neutral, so corroded that they had to cut back the cables, replace the neutral connector and reconnect.

[Derlyn]

When the prepaid meter trips on undervoltage it resets itself once every minute irrespective of whether the voltage has returned to acceptable levels or not.

That means that if the meter is not resetting itself once every minute, then it has NOT tripped on undervoltage. It is probably tripping on overcurrent as a result of too low a current setting on the meter or a faulty current detection circuit.

[sparktech]

I would suggest you measure the loads(Current) when checking the Voltage. In which Area is that?

[Mlb]

When the prepaid meter trips on undervoltage it resets itself once every minute irrespective of whether the voltage has returned to acceptable levels or not.

That means that if the meter is not resetting itself once every minute, then it has NOT tripped on undervoltage. It is probably tripping on overcurrent as a result of too low a current setting on the meter or a faulty current detection circuit.

The meter does reset itself every minute or so but not all the time. Eventually it gets locked out and I have to enter a code to get the power on. The meter also doesn't turn off completely. The display is still on showing the units so I would assume that the detection circuit is still functional and hence only resets when the voltage is at an acceptable level. Even if the meter is faulty I still have a no-load voltage of 216V at the main breaker with the meter bypassed. If I have to put the high current appliances on the voltage will drop below 200 which is surely unacceptable?

[Mlb]

I would suggest you measure the loads(Current) when checking the Voltage. In which Area is that?

Cape Town, Athlone, Belgravia

[sparktech]

i was trying to send you a private message. Not sure why that restriction. Send me a Pic of your Prepaid device privately.

[GCE]

Hi
One question I have not seen - Do you have solar and/or and inverter
Is the meter a Conlog BEC44

[Mlb]

Hi
One question I have not seen - Do you have solar and/or and inverter
Is the meter a Conlog BEC44

I've got a mecer inverter but the issue exists with with the main breaker off so the load on the circuit is irrelevant

[Mlb]

Update: Council separated my house from the neighbour by running a new cable from a different phase. It appears the voltage is now higher at peak time but still drops below 220 when I turn on high current appliances and the meter trips. I suspect there are multiple problems at play. Next step for them is to dig up the ground around the pole as there is a join on the armoured cable underground. By the way this is the meter I have https://rsauctioneers.bidpro.co.za/Lot/66840. It always trips at below 215V I'd say.

[GCE]

I've got a mecer inverter but the issue exists with with the main breaker off so the load on the circuit is irrelevant

Sounds like it is then just low voltage - I would ask supply authority to either change the set point or disable the set point

Acceptable levels according to SANS are between 207 up to 253 Volts


SANS10142-1
5.4.2 Voltage
The equipment shall be suitable for operation on the maximum steady (r.m.s.)
voltage and overvoltage to which it is likely to be subjected. Equipment shall
be rated in accordance with the intended application for use on one of the
following voltages used in South Africa:
a) A.C. circuits:
1) standard voltages at a point of supply of Amdt 1
i) 230 V single-phase,
ii) 230/400 V three-phase four-wire, and
a tolerance of ± 10 % on these voltages.
NOTE For certain equipment it may be necessary to consider the lowest voltage
that is likely to occur.