Marv

The arc fault detection devices are there to protect the final circuits in the house such as lighting circuits, socket circuits etc, they will also protect the DB to some extent as well. They don't detect light or smoke or any environmental factors, they have a built in computer/PIC that monitors the waveform on that circuit they're supplying for characteristics or a waveform footprint that might indicate an arc fault.
They're extremely technical devices with a test button like an earth leakage breaker but unlike an earth leakage breaker there's no way for a normal electrician to actually test if they work or not. There's often one or two small led indicator lamps built into the front of them that flash in numerous complicated sequences to indicate some info about the fault that caused them to trip.
They look like a normal DIN mount circuit breaker but they're usually single pole + N configuration contacts.


They can be prone to nuisance tripping with appliances that spark during their normal operation such as cooking appliance with a bi-metallic thermostat or even a drill with a brush motor. The way many manufacturers seem to be approaching the nuisance trip problem is to include a 'white list' in the internal program of the AFDD that has specific examples of waveforms from appliances that have been known to cause nuisance tripping in the past even though they are perfectly safe and functional.
Many of the AFDD's are wi-fi connected and automatically get firmware updates supposedly to improve their performance over time. Some AFDD's are not Wi-Fi connected and need to be manually 'flashed' to update their firmware which would need a visit from an electrician.
These devices are standard fitment in new installations in places like the UK, being driven by the requirements of the latest electrical regs.

The arc fault detection devices are there to protect the final circuits in the house such as lighting circuits, socket circuits etc, they will also protect the DB to some extent as well. They don't detect light or smoke or any environmental factors, they have a built in computer/PIC that monitors the waveform on that circuit they're supplying for characteristics or a waveform footprint that might indicate an arc fault.
They're extremely technical devices with a test button like an earth leakage breaker but unlike an earth leakage breaker there's no way for a normal electrician to actually test if they work or not. There's often one or two small led indicator lamps built into the front of them that flash in numerous complicated sequences to indicate some info about the fault that caused them to trip.
They look like a normal DIN mount circuit breaker but they're usually single pole + N configuration contacts.


They can be prone to nuisance tripping with appliances that spark during their normal operation such as cooking appliance with a bi-metallic thermostat or even a drill with a brush motor. The way many manufacturers seem to be approaching the nuisance trip problem is to include a 'white list' in the internal program of the AFDD that has specific examples of waveforms from appliances that have been known to cause nuisance tripping in the past even though they are perfectly safe and functional.
Many of the AFDD's are wi-fi connected and automatically get firmware updates supposedly to improve their performance over time. Some AFDD's are not Wi-Fi connected and need to be manually 'flashed' to update their firmware which would need a visit from an electrician.
These devices are standard fitment in new installations in places like the UK, being driven by the requirements of the latest electrical regs.

8.1.3
NOTE In South Africa, it is a statutory requirement that every user or lessor of an
electrical installation shall have a valid Certificate of Compliance (CoC) for every
such installation. A CoC will only be valid when it is accompanied by a test report
in the format of the test report in 8.7.
 
From the definitions in SANS10142;
3.33
electrical installation
machinery, in or on any premises, that is used for the transmission of
electrical energy from a point of control (see 3.56) to a point of
consumption (see 3.55) anywhere on the premises, including any article
that forms part of such an installation, irrespective of whether or not it is part
of the electrical circuit, but excluding
a) any machinery of the supplier that is related to the supply of electricity on
the premises,
b) any machinery that is used for the transmission of electricity of which the
voltage does not exceed 50 V, where such electricity is not derived from
the main supply of a supplier, and
c) any machinery that transmits electrical energy in telecommunication,
television or radio circuits
 
So if you have an off grid house and the voltage generated or distributed within the premises is 50v or less then you would be exempt from a CoC because it would no longer fulfil the definition of an 'electrical installation' under the exception provided in the definitions 3.33 paragraph b. In short regardless of whether you have an Eskom supply connection or not your house will require a CoC and all the electrical installation standards will still apply to any 230v electrical installation you have.
 

I'm all for energy conservation but LED lamps are relatively unreliable. I've still got some compact fluorescent lamps in my house and linear fluorescent tubes in my workshop which are over 10 years old and a few of them over 15 years. Even with with the epidemic of loadshedding followed by low voltage surges and generally appalling power quality these fluorescent lamps are still working fine.
I wish I could say the same for LED lamps but alas they're very unreliable and it's generally down to poor design, poor build quality and built-in obsolescence. You kinda expect it if you order lamps on Amazon or AliExpress but the majority of the LED lamps available over the counter from electrical wholesalers are equally as bad and they should be ashamed of themselves.
Don't get me wrong, there are well designed LED lamps with stable driver circuitry, good internal thermal management, decent power factor, good colour rendering but they're the exception rather than the rule and they're usually double if not triple the price of the rubbish options. When I was involved in relamping projects we installed hundreds of dimmable GU10 lamps in some premises and there were zero failures in the first 5 years so I know they can be reliable, it's just social, political and financial obsticles causing or allowing them to be generally unreliable.
I wish they would introduce not just electrical regs to ensure good power factor, low inrush currents and built in surge protection etc but also consumer protection legislation that it's illegal to sell LED lamps that don't last at least 3 years regardless of their usage pattern. Should any LED lamp fail within 3 years the vendor / electrical wholesaler / importer that supplied it should be financially on the hook not just for a replacement lamp but also for the item return costs and any labour costs including crane or cherry picker rental if required.
It should also be legislated that they're not allowed to dictate warranty validity on whether or not external surge protection is installed. What a load of horseshit. If the internal circuits of an LED lamp are well designed the risk of surge damage from supply instabilities can be adequately mitigated by decoupling control components and using stable power rails. Problem is when an electrical wholesaler attends the Beijing LED trade show and orders 100k of the cheapest LED lamps they can find the design they get means astronomically high failure rates and leaves them looking for any excuse they can find not to have to deal with the flood of warranty claims they get. Next thing you know there's small print somewhere on their website stating you're shit outta luck if your LED lamps only last 3 months because you didnt install 3 grands worth of class AB surge arrestors.
Anyway, apologies in advance because not sure how much of this will be tolerated by the forum bad word filters but rant over for now.

I'm all for energy conservation but LED lamps are relatively unreliable. I've still got some compact fluorescent lamps in my house and linear fluorescent tubes in my workshop which are over 10 years old and a few of them over 15 years. Even with with the epidemic of loadshedding followed by low voltage surges and generally appalling power quality these fluorescent lamps are still working fine.
I wish I could say the same for LED lamps but alas they're very unreliable and it's generally down to poor design, poor build quality and built-in obsolescence. You kinda expect it if you order lamps on Amazon or AliExpress but the majority of the LED lamps available over the counter from electrical wholesalers are equally as bad and they should be ashamed of themselves.
Don't get me wrong, there are well designed LED lamps with stable driver circuitry, good internal thermal management, decent power factor, good colour rendering but they're the exception rather than the rule and they're usually double if not triple the price of the rubbish options. When I was involved in relamping projects we installed hundreds of dimmable GU10 lamps in some premises and there were zero failures in the first 5 years so I know they can be reliable, it's just social, political and financial obsticles causing or allowing them to be generally unreliable.
I wish they would introduce not just electrical regs to ensure good power factor, low inrush currents and built in surge protection etc but also consumer protection legislation that it's illegal to sell LED lamps that don't last at least 3 years regardless of their usage pattern. Should any LED lamp fail within 3 years the vendor / electrical wholesaler / importer that supplied it should be financially on the hook not just for a replacement lamp but also for the item return costs and any labour costs including crane or cherry picker rental if required.
It should also be legislated that they're not allowed to dictate warranty validity on whether or not external surge protection is installed. What a load of horseshit. If the internal circuits of an LED lamp are well designed the risk of surge damage from supply instabilities can be adequately mitigated by decoupling control components and using stable power rails. Problem is when an electrical wholesaler attends the Beijing LED trade show and orders 100k of the cheapest LED lamps they can find the design they get means astronomically high failure rates and leaves them looking for any excuse they can find not to have to deal with the flood of warranty claims they get. Next thing you know there's small print somewhere on their website stating you're shit outta luck if your LED lamps only last 3 months because you didnt install 3 grands worth of class AB surge arrestors.
Anyway, apologies in advance because not sure how much of this will be tolerated by the forum bad word filters but rant over for now.

I'm all for energy conservation but LED lamps are relatively unreliable. I've still got some compact fluorescent lamps in my house and linear fluorescent tubes in my workshop which are over 10 years old and a few of them over 15 years. Even with with the epidemic of loadshedding followed by low voltage surges and generally appalling power quality these fluorescent lamps are still working fine.
I wish I could say the same for LED lamps but alas they're very unreliable and it's generally down to poor design, poor build quality and built-in obsolescence. You kinda expect it if you order lamps on Amazon or AliExpress but the majority of the LED lamps available over the counter from electrical wholesalers are equally as bad and they should be ashamed of themselves.
Don't get me wrong, there are well designed LED lamps with stable driver circuitry, good internal thermal management, decent power factor, good colour rendering but they're the exception rather than the rule and they're usually double if not triple the price of the rubbish options. When I was involved in relamping projects we installed hundreds of dimmable GU10 lamps in some premises and there were zero failures in the first 5 years so I know they can be reliable, it's just social, political and financial obsticles causing or allowing them to be generally unreliable.
I wish they would introduce not just electrical regs to ensure good power factor, low inrush currents and built in surge protection etc but also consumer protection legislation that it's illegal to sell LED lamps that don't last at least 3 years regardless of their usage pattern. Should any LED lamp fail within 3 years the vendor / electrical wholesaler / importer that supplied it should be financially on the hook not just for a replacement lamp but also for the item return costs and any labour costs including crane or cherry picker rental if required.
It should also be legislated that they're not allowed to dictate warranty validity on whether or not external surge protection is installed. What a load of horseshit. If the internal circuits of an LED lamp are well designed the risk of surge damage from supply instabilities can be adequately mitigated by decoupling control components and using stable power rails. Problem is when an electrical wholesaler attends the Beijing LED trade show and orders 100k of the cheapest LED lamps they can find the design they get means astronomically high failure rates and leaves them looking for any excuse they can find not to have to deal with the flood of warranty claims they get. Next thing you know there's small print somewhere on their website stating you're shit outta luck if your LED lamps only last 3 months because you didnt install 3 grands worth of class AB surge arrestors.
Anyway, apologies in advance because not sure how much of this will be tolerated by the forum bad word filters but rant over for now.

Single or 3-phase is a tricky one.
What equipment and appliances are you running? There's some things that are better 3-phase like motors/pumps/compressors, the single phase versions have much higher and prolonged start currents which can cause inverters to trip. Inverter air conditioning is a good way to reduce start currents.
I'd suggest a full load audit where you list every single electrical appliance along with its kwh consumption, start/run currents etc. Then as Calvin suggests look at the low hanging fruit such as air con, hot water geysers, cooking stoves, halogen lighting, fridges/freezers sitting in a hot outhouse etc and see which appliances are worth replacing with gas for example or maybe even worth buying a newer version that's more efficient. Then plan your solar requirements after that.

Don't run an electrical circuit outside of the boundaries of the ERF it's supplied from, it's in violation of the electrical regs and also in violation of the terms and conditions of the Eskom supply. Theres good safety resaons not to do this which without getting too technical you can cause a shock hazard by connecting adjacent equipotential earthing zones together or even having them too close to each other. It all depends what the earthing arrangements are at the properties where the circuits originate but the answer in short is no, do not run more than one circuit from different properties to supply the pump.
 
As already mentioned you could meter the power the pump is using and just divide the cost amicably or you could pump the water into a holding tank then run 3 water pipes from there to supply the 3 properties and meter the volume of water each property uses and divide the bill up that way.
 
Just incidentally I'd suggest you come up with an arrangement where everyone pays double what the power cost is every month and save the excess payments in an account so when the pump goes tits-up a year or two from now there's already money available towards repairs or replacing.

Don't run an electrical circuit outside of the boundaries of the ERF it's supplied from, it's in violation of the electrical regs and also in violation of the terms and conditions of the Eskom supply. Theres good safety resaons not to do this which without getting too technical you can cause a shock hazard by connecting adjacent equipotential earthing zones together or even having them too close to each other. It all depends what the earthing arrangements are at the properties where the circuits originate but the answer in short is no, do not run more than one circuit from different properties to supply the pump.
 
As already mentioned you could meter the power the pump is using and just divide the cost amicably or you could pump the water into a holding tank then run 3 water pipes from there to supply the 3 properties and meter the volume of water each property uses and divide the bill up that way.
 
Just incidentally I'd suggest you come up with an arrangement where everyone pays double what the power cost is every month and save the excess payments in an account so when the pump goes tits-up a year or two from now there's already money available towards repairs or replacing.

Earth leakage breakers almost never go faulty. I'd guess that out of every couple of hundred earth leakage tripping faults one might be cause by a faulty earth leakage breaker. If there's a fault the earth leakage breaker will reset if the power to it is off then trip if the power is put back on, this is normal.
Earth leakage breakers are sensitive to faults on circuits they supply even if the circuit breaker for that circuit is switched off. This is because the earth leakage is monitoring both the live and the neutral wires and the circuit breaker only disconnects the live and the neutral remains connected.
If this is a new installation or if there have been changes to the installation recently then it's possibly a wiring fault within the installation.
If the fault started out of the blue then it's more likely an appliance that's faulty in which case unplug all appliances completely from all sockets and see if the fault goes away.
Some other things you can check are outside lights or connection boxes that might have leaked water or suffered an insect infestation. Check the geyser for water leaks or condensation where the wiring connects into it. Check for any signs of damp on the ceiling inside, maybe an internal light got wet.

Apologies, I didn't see the thermoplastic classification. It won't be XLPE in that case, maybe polyurethene or some kinda PVC. I wish they'd just state the actual plastic they use rather than the family of plastics, it would be a lot more useful. Problem nowadays there's so many variations of each plastic even that wouldn't really help because they're all chemically cocktailed to their specific application meaning there's dozens of variations of PVC so you'd have to use the IEC 60811 classification which wouild be complicated but handy if you're considering a cable for an application that's unusual.
I think manufacturers just need to produce better data sheets that are more relevant to ever evolving modern day uses. Twenty years ago a simple temp and CCC rating with different installation methods was fine but nowadays it's way short of the mark. They should state figures that indicate their suitabiliy for AC (normal 230/400v supply), DC such as solar PV etc, high frequency AC and modulated DC for VFD applications etc. Unfortunately that's not going to happen unless there's legislation or a requirement in the 10142 regs for it to be supplied on products sold. 
 

Agree with Timbo, Enlite rebranded as Aurora a while back. The Enlite lamps were superb, I installed 160 in one retail outlet about 5 years ago and there wasn't a single failure to date. The power factor was superb, the dimming curve is silky smooth and very stable at all levels and the colour rendering is very good. They weren't cheap but overall good value and I'd highly recommend them as a brand.

Refrigeration is often overlooked or ignored when looking for energy savings.
 
Cleaning the condensor and/or improving air circulation around the fridge can reduce the energy it consumes by 20%... or a lot more if it's a commercial underbar type fridge. Ive seen up to 40% energy saving with condensors being cleaned on commercial underbar units. Even domestic fridges have small condensor fans sometimes, check they're working and dust free.
Check the door gasket for damage and replace if necessary, also angle the fridge slightly backwards so the door has a better tendancy to close on its own.
Use your cellphone to check the internal lights switch off when the door closes.
If you fridge or freezer needs manually defrosting do so regularly, don't wait until there's thick ice built up inside it. If it needs defrosting more than once every couple of months check the door gasket and the door hinge adjustment. I've seen old fridges where the plastic washer in the hinge has broken and fallen out causing the door to drop down about 5mm and leave a thin air-gap along the top of the gasket when the door is closed and most people wouldn't be tall enought to notice this.
Check the temperature isn't set too low, if it is then thermal losses through the insulation become excessive. Don't use glass door fridges unless you really have to, they have higher thermal losses through the door than a regular fridge. If the fridge feels cold on the outside of the cabinet or it has areas on the cabinet where condensation forms, assuming the internal temp is correct then get rid of it (preferrably check it with a thermal camera if possible). Always buy a fridge with a minimum of A++ energy rating. I've also seen chest freezers where the thin aluminium internal liner has become damaged by frozen food being dropped inside it, this led to the foam in the base area becoming water logged and losing its insulation which in turn meant the compressor was running 24/7.
Locate fridges and freezers in a cool and ventilated room without direct sunlight.  I've seen a 30% energy saving where domestic fridges were in a small room with polycarbonate roof and direct sunlight from big windows and they were moved to inside the garage where it was much cooler ambient temp. This will also enormously  improve the compressor lifespan.
There's an urban myth that says it's not good to turn fridges off. I'm guessing it's because if a fridge has a slow gas leak it might leak quicker if the fridge isn't running. Ignore it, if you have a fridge that's empty don't leave it on to unnecessarily consume energy; rather run one full fridge than two half empty ones. On the one in a thousand chance your fridge does have a gas leak it will already be highly inefficient and needs fixing or replacing anyway so you've got nothing to lose in the long term.

What type of earth leakage breaker is it? If it's an 'AC' type you could be looking for AC leakage with a DC component to it.
As above, earth leakage breakers are known to sometimes nuisance trip when power is restored. They can be sensitive to downstream and upstream harmonics and phase angle disturbances which can occur depending on the type of load connected.
0 & 180 degree ramp test the earth leakage and check trip times at .5x, 1x and 5x. Do an IR test with L+N combined and earth but also test global leakage current as a live test with a clamp meter around the L+N on the earth leakage load side. If these tests give good results then you can add an extra earth leakage breaker and split the circuits between the two assuming there's space or alternatively try a different brand of earth leakage breaker.

Refrigeration is often overlooked or ignored when looking for energy savings.
 
Cleaning the condensor and/or improving air circulation around the fridge can reduce the energy it consumes by 20%... or a lot more if it's a commercial underbar type fridge. Ive seen up to 40% energy saving with condensors being cleaned on commercial underbar units. Even domestic fridges have small condensor fans sometimes, check they're working and dust free.
Check the door gasket for damage and replace if necessary, also angle the fridge slightly backwards so the door has a better tendancy to close on its own.
Use your cellphone to check the internal lights switch off when the door closes.
If you fridge or freezer needs manually defrosting do so regularly, don't wait until there's thick ice built up inside it. If it needs defrosting more than once every couple of months check the door gasket and the door hinge adjustment. I've seen old fridges where the plastic washer in the hinge has broken and fallen out causing the door to drop down about 5mm and leave a thin air-gap along the top of the gasket when the door is closed and most people wouldn't be tall enought to notice this.
Check the temperature isn't set too low, if it is then thermal losses through the insulation become excessive. Don't use glass door fridges unless you really have to, they have higher thermal losses through the door than a regular fridge. If the fridge feels cold on the outside of the cabinet or it has areas on the cabinet where condensation forms, assuming the internal temp is correct then get rid of it (preferrably check it with a thermal camera if possible). Always buy a fridge with a minimum of A++ energy rating. I've also seen chest freezers where the thin aluminium internal liner has become damaged by frozen food being dropped inside it, this led to the foam in the base area becoming water logged and losing its insulation which in turn meant the compressor was running 24/7.
Locate fridges and freezers in a cool and ventilated room without direct sunlight.  I've seen a 30% energy saving where domestic fridges were in a small room with polycarbonate roof and direct sunlight from big windows and they were moved to inside the garage where it was much cooler ambient temp. This will also enormously  improve the compressor lifespan.
There's an urban myth that says it's not good to turn fridges off. I'm guessing it's because if a fridge has a slow gas leak it might leak quicker if the fridge isn't running. Ignore it, if you have a fridge that's empty don't leave it on to unnecessarily consume energy; rather run one full fridge than two half empty ones. On the one in a thousand chance your fridge does have a gas leak it will already be highly inefficient and needs fixing or replacing anyway so you've got nothing to lose in the long term.

I have an Axpert Mk _ 5000  inverter. Used it for a year. Then the solar function gave in. For some reason the batteries fried.
BUT it was working perfectly fine as long as you disconnect the panels.
So, it still functioned perfectly as an inverter-charger as long as you don't worship the sun.
Free to a good home.
I also had x 3 Victron battery balancers (which worked perfectly before the Axpert fried the Omni battery bank)
- also to a good home.
 
whoever is first to respond gets it. But take it all. I cannot sukkel with item by item. My nerves are shot anyway.
 
The Axpert is perfect as a charger/ load-shed backup. Just don't attach panels.
I upgraded to Victron with great regret at my rash decision to connect panels to the Axpert.
Now you can have it for free - which does not reflect on you at all as the load shedding function is still perfect!!

Kind of a silly situation - Inverter (VSD) being driven by another inverter - if there was more demand, there might be an integrated solution that would make more sense - grid tied inverter with variable frequency output.
 
Anyway, my actual reason for responding - just cautionary note @Marv . You might be aware if this already, but if you have cause to deal with fans (I assume by 'air movement' you mean a fan of some sort) in future - especially bigger units, they are often high inertia machines and have longish run up times the startup current spike at 6-7x full load amps is accordingly long  - this is particularly true of larger, slower running fans. i.e. they are under high mechanical load start.
Obviously the above goes away with a VSD, I've seen a number of folk bitten with DOL starts on fans.

I'll take a stab at question 1.
Best way to calculate start current (also called inrush current or surge current) is to actually measure it with a suitable electrical tester. The only problem is that testers that can accurately give you a start current reading are expensive and outside the reach of DIY'ers so you'd need to either hire one or find an electrician who's got one.
We also use a rule of thumb where we allow that the start current could be up to 5x the run current for a single phase motor and you can measure the run current using a cheap and cheerful clamp meter or one of those kill-a-watt type power testers.
 

Hi @Marv
Cheapest option may be to replace the 3-phase VSD's with single phase VSD drives that can supply the 3-Phase motors.
About R3k for a 2.2kw VSD https://cfptechnologies.co.za/product/veichi-ac10/ 
You will then only need to have single phase inverters and as the VSD's can be configured for a soft-start so should be relatively light on the inverters. 

I'll take a stab at question 1.
Best way to calculate start current (also called inrush current or surge current) is to actually measure it with a suitable electrical tester. The only problem is that testers that can accurately give you a start current reading are expensive and outside the reach of DIY'ers so you'd need to either hire one or find an electrician who's got one.
We also use a rule of thumb where we allow that the start current could be up to 5x the run current for a single phase motor and you can measure the run current using a cheap and cheerful clamp meter or one of those kill-a-watt type power testers.
 

Start at the beginning, do a power audit of all the items you want to run on the inverter to get an accurate handle on exactly what the load is. You might be surprised and it's less than 40Amps in which case you've got cheap options. If it's more than 40 Amps I'd strongly suggest you make some sacrifices to bring it under otherwise you're in for an expensive and complex installation.
 
I wouldn't consider getting council to give you a larger single phase supply as a good option, often with the old 40A 3-phase supplies they'll only have a 6mmx4-core cable for the incomer in which case they'll whack you for the cost of a new 16mm x 2-core cable as well as another few grand for a new energy dispenser plus your new supply will only be effectively half the size of your existing one.
 
**edit** Oops...just saw the date the Jaco_n posted this.

Refrigeration is often overlooked or ignored when looking for energy savings.
 
Cleaning the condensor and/or improving air circulation around the fridge can reduce the energy it consumes by 20%... or a lot more if it's a commercial underbar type fridge. Ive seen up to 40% energy saving with condensors being cleaned on commercial underbar units. Even domestic fridges have small condensor fans sometimes, check they're working and dust free.
Check the door gasket for damage and replace if necessary, also angle the fridge slightly backwards so the door has a better tendancy to close on its own.
Use your cellphone to check the internal lights switch off when the door closes.
If you fridge or freezer needs manually defrosting do so regularly, don't wait until there's thick ice built up inside it. If it needs defrosting more than once every couple of months check the door gasket and the door hinge adjustment. I've seen old fridges where the plastic washer in the hinge has broken and fallen out causing the door to drop down about 5mm and leave a thin air-gap along the top of the gasket when the door is closed and most people wouldn't be tall enought to notice this.
Check the temperature isn't set too low, if it is then thermal losses through the insulation become excessive. Don't use glass door fridges unless you really have to, they have higher thermal losses through the door than a regular fridge. If the fridge feels cold on the outside of the cabinet or it has areas on the cabinet where condensation forms, assuming the internal temp is correct then get rid of it (preferrably check it with a thermal camera if possible). Always buy a fridge with a minimum of A++ energy rating. I've also seen chest freezers where the thin aluminium internal liner has become damaged by frozen food being dropped inside it, this led to the foam in the base area becoming water logged and losing its insulation which in turn meant the compressor was running 24/7.
Locate fridges and freezers in a cool and ventilated room without direct sunlight.  I've seen a 30% energy saving where domestic fridges were in a small room with polycarbonate roof and direct sunlight from big windows and they were moved to inside the garage where it was much cooler ambient temp. This will also enormously  improve the compressor lifespan.
There's an urban myth that says it's not good to turn fridges off. I'm guessing it's because if a fridge has a slow gas leak it might leak quicker if the fridge isn't running. Ignore it, if you have a fridge that's empty don't leave it on to unnecessarily consume energy; rather run one full fridge than two half empty ones. On the one in a thousand chance your fridge does have a gas leak it will already be highly inefficient and needs fixing or replacing anyway so you've got nothing to lose in the long term.

Refrigeration is often overlooked or ignored when looking for energy savings.
 
Cleaning the condensor and/or improving air circulation around the fridge can reduce the energy it consumes by 20%... or a lot more if it's a commercial underbar type fridge. Ive seen up to 40% energy saving with condensors being cleaned on commercial underbar units. Even domestic fridges have small condensor fans sometimes, check they're working and dust free.
Check the door gasket for damage and replace if necessary, also angle the fridge slightly backwards so the door has a better tendancy to close on its own.
Use your cellphone to check the internal lights switch off when the door closes.
If you fridge or freezer needs manually defrosting do so regularly, don't wait until there's thick ice built up inside it. If it needs defrosting more than once every couple of months check the door gasket and the door hinge adjustment. I've seen old fridges where the plastic washer in the hinge has broken and fallen out causing the door to drop down about 5mm and leave a thin air-gap along the top of the gasket when the door is closed and most people wouldn't be tall enought to notice this.
Check the temperature isn't set too low, if it is then thermal losses through the insulation become excessive. Don't use glass door fridges unless you really have to, they have higher thermal losses through the door than a regular fridge. If the fridge feels cold on the outside of the cabinet or it has areas on the cabinet where condensation forms, assuming the internal temp is correct then get rid of it (preferrably check it with a thermal camera if possible). Always buy a fridge with a minimum of A++ energy rating. I've also seen chest freezers where the thin aluminium internal liner has become damaged by frozen food being dropped inside it, this led to the foam in the base area becoming water logged and losing its insulation which in turn meant the compressor was running 24/7.
Locate fridges and freezers in a cool and ventilated room without direct sunlight.  I've seen a 30% energy saving where domestic fridges were in a small room with polycarbonate roof and direct sunlight from big windows and they were moved to inside the garage where it was much cooler ambient temp. This will also enormously  improve the compressor lifespan.
There's an urban myth that says it's not good to turn fridges off. I'm guessing it's because if a fridge has a slow gas leak it might leak quicker if the fridge isn't running. Ignore it, if you have a fridge that's empty don't leave it on to unnecessarily consume energy; rather run one full fridge than two half empty ones. On the one in a thousand chance your fridge does have a gas leak it will already be highly inefficient and needs fixing or replacing anyway so you've got nothing to lose in the long term.

Refrigeration is often overlooked or ignored when looking for energy savings.
 
Cleaning the condensor and/or improving air circulation around the fridge can reduce the energy it consumes by 20%... or a lot more if it's a commercial underbar type fridge. Ive seen up to 40% energy saving with condensors being cleaned on commercial underbar units. Even domestic fridges have small condensor fans sometimes, check they're working and dust free.
Check the door gasket for damage and replace if necessary, also angle the fridge slightly backwards so the door has a better tendancy to close on its own.
Use your cellphone to check the internal lights switch off when the door closes.
If you fridge or freezer needs manually defrosting do so regularly, don't wait until there's thick ice built up inside it. If it needs defrosting more than once every couple of months check the door gasket and the door hinge adjustment. I've seen old fridges where the plastic washer in the hinge has broken and fallen out causing the door to drop down about 5mm and leave a thin air-gap along the top of the gasket when the door is closed and most people wouldn't be tall enought to notice this.
Check the temperature isn't set too low, if it is then thermal losses through the insulation become excessive. Don't use glass door fridges unless you really have to, they have higher thermal losses through the door than a regular fridge. If the fridge feels cold on the outside of the cabinet or it has areas on the cabinet where condensation forms, assuming the internal temp is correct then get rid of it (preferrably check it with a thermal camera if possible). Always buy a fridge with a minimum of A++ energy rating. I've also seen chest freezers where the thin aluminium internal liner has become damaged by frozen food being dropped inside it, this led to the foam in the base area becoming water logged and losing its insulation which in turn meant the compressor was running 24/7.
Locate fridges and freezers in a cool and ventilated room without direct sunlight.  I've seen a 30% energy saving where domestic fridges were in a small room with polycarbonate roof and direct sunlight from big windows and they were moved to inside the garage where it was much cooler ambient temp. This will also enormously  improve the compressor lifespan.
There's an urban myth that says it's not good to turn fridges off. I'm guessing it's because if a fridge has a slow gas leak it might leak quicker if the fridge isn't running. Ignore it, if you have a fridge that's empty don't leave it on to unnecessarily consume energy; rather run one full fridge than two half empty ones. On the one in a thousand chance your fridge does have a gas leak it will already be highly inefficient and needs fixing or replacing anyway so you've got nothing to lose in the long term.

@Marv check under the error 09 post, you will see i posted some repair manuals of this units. All the info is there. I see you in CapeTown side. Let me know if you got it fixed, i got a 48v 5000w unit thats giving problem to. Luckily nothing burned but still cant get it running after replacing some stuff.