There is always some curve ball in life that upsets the plans. Yesterday there is commotion in the street as the pre paid meter squad is ripping out meters out of the street box.

My neighbor who has the same system as me is one of the victims. The contractor handed him a pre paid meter and said plug this in, it should work.

Issue no 1

Non of his plugs would work to power this thing. The contractor is saying that he needs a direct to Eksdom plug. Like me his system is all on essential there is no split DB.

How do we fix this ?

Issue no 2

I have ordered a 2nd 120 amp battery. Please let me know if this is right.

Switch everything off

Connect red to red

Connect black to black

Connect communication cable

In my manual for the battery it states for ADS, set dip switches

0 off, off, off, off
1 On, off, off, off

Turn on inverter

Turn on batteries

Turn on PV

Turn on AC

Does this sound right to you.?

Thanks in advance.

Edited October 22, 20241 yr by Stranger

Pre-paid meters (at least in Zimbabwe) come in two parts; the main part that is connected to the utility directly and power runs through to your house/loads and a second human machine interface (HMI) unit that allows you to enter recharge codes, check balances etc. The HMI is typically plugged into a free socket and communicates via the socket wiring back to the main unit. You do not need the HMI connected at all times but to check balances, enter voushers etc it needs to be connected to the main unit. When an inverter is inverting and supplying power, it may or may not break the connection back to the utility depending on inverter design and/or anti-islanding requirements. I suspect this is why the contractor said you need an Eskom only socket.

Hopefully your installer included a bypass switch for your inverter so that you can remove the inverter from circuit and run solely on Eskom? This would accomplish the requirement of having a Eskom only socket and allow communication between HMI and main unit when it's needed. It is a good back up to allow your system to run while the inverter is being maintained or if there is a failure. You might want to have an Eskom only socket fitted near your utility connection to leave the HMI plugged in for ease of use?

Regarding your new battery:

1. Double check warranty and wiring regulations regarding fusing and battery connection. Some manufacturers require independent fuses and connections to a bus bar per battery
2. I would typically recommend that the batteries are turned on before the inverter

Other steps all seem fine. You should also check the maximum allowable charge current to the battery. This may need to be adjusted.

Try and get the batteries up to the same voltage, otherwise you get a big spark and might cause issues, do you have a busbar that you connect them to? Did you mean 120 KWH battery, that is huge?

5 minutes ago, Greglsh said:

Try and get the batteries up to the same voltage, otherwise you get a big spark and might cause issues, do you have a busbar that you connect them to? Did you mean 120 KWH battery, that is huge?

Oops my bad, meant 120 amp

My system is 5.5 kw inverter

12 440 w panels

currently 1 x 48 v 120 amp battery

1 hour ago, Stranger said:

Non of his plugs would work to power this thing. The contractor is saying that he needs a direct to Eksdom plug. Like me his system is all on essential there is no split DB.

How do we fix this ?

This is a common issue with pre-paid meters. The interface unit (what you use to enter the tokens for your purchases) communicates with the actual meter via the house wiring. The moment you have anything other else between the interface and the unit the communication breaks down and although the meter itself will still work (whilst you have a credit) the interface unit will have no communications with the meter because of all the circuitry between the two. Remember that in your scenario, everything is connected to the output side of an inverter.

I had a similar problem when I got a new pre-paid meter fitted earlier this year. One solution for me was to just plug the interface into a non-backed up circuit. EG the outbuildings. But that would be a problem for the wife. Everything inside the house is backed up, so I had an electrician fit one  plug that is directly connected to the incoming grid feed. This is clearly labelled as being connected to the grid, not the inverter, and has it's own breaker.

Problem solved. The meter now stays fixed to the wall, next to the inverter, and I don't have to run around in the dark (and sometimes the wet) to load a purchase. A beneficial side effect is that the meter has it's own power/status LED. Now nobody has to decode the row of LEDs on the front panel of my Goodwe, or consult an app on their phone. If that LED is off then the grid is down.

Edited October 22, 20241 yr by Bobster.
Sppeling. Clarity

1 hour ago, Stranger said:

There is always some curve ball in life that upsets the plans. Yesterday there is commotion in the street as the pre paid meter squad is ripping out meters out of the street box.

You don't say where you are, but you should take some precautions and expect some visits to inspect the meter.

Your useage and thus your purchases are going to be low. This will likely cause a blip on the service provider's system and they will send people out to have a look. They are looking for bridging of the meter. It is nothing personal - don't feel accused. The guy who comes out is just investigating. There is another, legitimate reason why your use is low, so they should not find against you.

From that comes another concern. Here in Johannesburg, in the areas serviced by City Power, if you don't feed your meter for (I'm told by one of their technicians) three months then their systems flag you for disconnection. Check with your service provider and see how long you can leave it. Or just buy a small amount each month.

They now know you have solar installed. I speak again as COJ customer. In theory, for some years now, inverters and batteries do not have to be declared, but any system that generates power  (which would include roof top solar) and has any sort of connection to the grid (even if you don't use that connection) has to be registered with the municipality. This is not an entirely bad thing (in Jhb) as part of the registration process involves them testing various safety features of your system. So I now have a nice letter saying that my system is fully compliant and I have given my insurers a copy. In Johannesburg, at the moment, they are allowing retrospective registration. IE you installed without applying first (which is how it's supposed to happen), but you're talking to them now and they will register the system as long as it passes muster (you also need an engineer to sign off). At some time (unknown to us) they may start enforcing this by-law more vigourously, and under those by-laws they do not have the right to remove your system, but they do have the right to disconnect you from their grid. 

If you are feeding back into the grid, the new meter is probably going to block that. Either by tripping, or by just not allowing any flow from the house to the grid. This is the situation I have, but (again, in Johannesburg) the tariffs are so unattractive that I have no interest in feeding back, and so I have set it not to, which gives my inverter a breather when the battery is charged.

Edited October 22, 20241 yr by Bobster.
Spppeling

Thanks

I am in Alberton and my inverter does not have a feed back option. Like yesterday though, no nice knock on the door for my neighbors, they just rocked up and started pulling meters out of the box.

OK, does this help

My DB board goes to the changeover switch,
this then goes to an AVP, AC in and AC out
This then goes to a mini DB with breakers AC in and AC out
this then goes to the inverter

Would the AC in line be a direct connection ?

 

5 hours ago, Stranger said:

I have ordered a 2nd 120 amp battery. Please let me know if this is right.

Is this the same make and model as you already have?

under LiFePO4 batteries you get 15 cell versions, 48V nominal and 16 cell versions 51.2V nominal, they do not co-exist on the same inverter(s)... you also get NMC type Lithium Ion batteries, usually 13 cell batteries, probably around 48.1V nominal, either way these 3 batteries will not co-exist, so for your setup, you'd need to ensure that whatever you are adding to your existing battery, is the same cell chemistry and number of cells in the battery...

If you have ordered the same make & model battery as you already have, then you can ignore the above paragraph...

Mine is NMC and is exactly the same battery as the original. I know I am going to have to get both to the same Voltage before I connect, but I have plan for that. It is the dip switches that concern me.