The right inverter for battery storage and some other Qs

[ALAN/ALAN D]

Convert all house lights to work off battery system. All mine been running for years with no failures.
Convert fridge / freezer to run off inverter EPS output system.

Anything else you can fix in the morning. When you get up.

[sharpener]

Convert all house lights to work off battery system. All mine been running for years with no failures.
Convert fridge / freezer to run off inverter EPS output system.

Anything else you can fix in the morning. When you get up.

Sound advice.

Anything beyond that you will have to post a list of everything that is in your present CU - including any blank ways - and what each serves, with current ratings.

[ducabi]

Convert all house lights to work off battery system. All mine been running for years with no failures.
Convert fridge / freezer to run off inverter EPS output system.

Anything else you can fix in the morning. When you get up.

Thanks! That's what I will be aiming for.

Anything beyond that you will have to post a list of everything that is in your present CU - including any blank ways - and what each serves, with current ratings.

What current limit do i have on my HYD3600? Tbf I shouldn't exceed 3000W if i switch off the biggest appliances (ie washing machine, dishwasher and oven) but I'm not sure yet if all of them are on a specific circuit.
If not, could i have the whole house on UPS side and just remember not to use too much W if it's running on batteries? It's just theoretical question as I'm sure my wife would easily exceed it by making coffee and using hair dryer at the same time.

[ALAN/ALAN D]

Quote. “I'm sure my wife would easily exceed it by making coffee and using hair dryer at the same time. “

It worked well for me. Initially I printed A4 sheets of paper explaining about not turning things on at the same time.
That did not work.
When the Lady got FINED £20 a time for doing it. The payback was pretty good.
Over time the Payback reduced. It worked.
The only time I get payback now is if she goes on Holiday for a week.
When she gets back I get some Initial payments.

[sharpener]

Anything beyond that you will have to post a list of everything that is in your present CU - including any blank ways - and what each serves, with current ratings.

What current limit do i have on my HYD3600? Tbf I shouldn't exceed 3000W if i switch off the biggest appliances (ie washing machine, dishwasher and oven) but I'm not sure yet if all of them are on a specific circuit.
If not, could i have the whole house on UPS side and just remember not to use too much W if it's running on batteries? It's just theoretical question as I'm sure my wife would easily exceed it by making coffee and using hair dryer at the same time.

Some further gleanings from the manual:

LOAD connection port is only for critical load connection. The power of critical loads must be less than 3000VA.
EPS (Emergency Power Supply) data
EPS rated power 3000VA
EPS nominal voltage/frequency 230V, 50/60Hz
EPS rated current 13.2A

I haven't found any mention of what happens if you exceed this. So I think you would be wise not to draw more than 13.2A from the EPS output even if the grid is working. Best get a 1000W travel kettle. Don't connect the ring mains, cooker or immersion heater circuits to it. Boiler would be all right if separate.

Safety protection: Anti-islanding, RCMU*, ground fault monitoring

*https://www.technosun.com/descargas/SCH ... ual-EN.pdf

Earth Fault Alarm
This inverter complies with IEC 62109-2 clause 13.9 for earth fault alarm monitoring.
If an Earth Fault Alarm occurs, the fault will be displayed on the LCD screen,the red light will be on,and the
fault can be found in the history of the fault.

There is also mention in the Fault Finding section of a GFCI (Ground Fault Circuit Interruptor - which is American for RCD)
So it would appear there is some kind of built-in leakage detection. A GFCI will disconnect the faulty circuit, and RCMU will only send a warning signal.

[ducabi]

I haven't found any mention of what happens if you exceed this. So I think you would be wise not to draw more than 13.2A from the EPS output even if the grid is working. Best get a 1000W travel kettle. Don't connect the ring mains, cooker or immersion heater circuits to it. Boiler would be all right if separate.

I don't understand this part. What does it mean, using EPS when grid is working? My primary reason for using the inverter is to run house on cheap energy by charging battery during night and discharging during the day.

[Oldgreybeard]

Some further gleanings from the manual:

LOAD connection port is only for critical load connection. The power of critical loads must be less than 3000VA.
EPS (Emergency Power Supply) data
EPS rated power 3000VA
EPS nominal voltage/frequency 230V, 50/60Hz
EPS rated current 13.2A

I haven't found any mention of what happens if you exceed this. So I think you would be wise not to draw more than 13.2A from the EPS output even if the grid is working. Best get a 1000W travel kettle. Don't connect the ring mains, cooker or immersion heater circuits to it. Boiler would be all right if separate.

Safety protection: Anti-islanding, RCMU*, ground fault monitoring

*https://www.technosun.com/descargas/SCH ... ual-EN.pdf

Earth Fault Alarm
This inverter complies with IEC 62109-2 clause 13.9 for earth fault alarm monitoring.
If an Earth Fault Alarm occurs, the fault will be displayed on the LCD screen,the red light will be on,and the
fault can be found in the history of the fault.

There is also mention in the Fault Finding section of a GFCI (Ground Fault Circuit Interruptor - which is American for RCD)
So it would appear there is some kind of built-in leakage detection. A GFCI will disconnect the faulty circuit, and RCMU will only send a warning signal.

TBH, I wasn't at all sure what happens if the inverter gets overloaded when running in EPS mode. The manual for mine states that it can deliver 3kVA (13A) from the Load side (the EPS output) but the only clue that it probably has internal overload protection is that there is a fault code for a current overload.

I also pondered about the cable protection requirements, given that in my case the inverter is well in excess of the 3m cable length limit for only having over current protection at one end of a bidirectional cable. This doesn't seem to be something mentioned anywhere that I found, but the regs require that cables be protected from over-current at source, normally, the only exception being that cables under 3m long (normally just meter tails) can be protected at the load end.

My fix for this also partially addresses the overload issue. I fitted 16A MCBs in a small consumer unit next to the inverter. These protect both the load and grid cables when the inverter is supplying current to the house (either in normal mode or in EPS mode). At the house end both these cables are protected by RCBOs. This seemed logical to me, as it means that the long cables from the inverter that run into the house are protected both ways, whether current is flowing to the inverter in battery charging mode, or flowing from the inverter when the batteries are discharging either in grid mode or EPS mode.

Anyone any thoughts on this? I'll admit to just doing it because it seemed a requirement in the regs to over-current protect any cable over 3m long at source, but I did my C&G back in the late 1970's, when regs were hardback and only cost a couple of quid (rather than the £££ I had to fork out for a copy of the 17th Edition a few years ago).

[marshman]

__

[sharpener]

I haven't found any mention of what happens if you exceed this. So I think you would be wise not to draw more than 13.2A from the EPS output even if the grid is working. Best get a 1000W travel kettle. Don't connect the ring mains, cooker or immersion heater circuits to it. Boiler would be all right if separate.

I don't understand this part. What does it mean, using EPS when grid is working? My primary reason for using the inverter is to run house on cheap energy by charging battery during night and discharging during the day.

I didn't say using EPS when the grid is working. I said not to draw more than 13.2A from the EPS output even when the grid is working.

The critical loads remain connected to the EPS output all the time. If the grid is working the inverter does not work in EPS mode drawing power from the battery so it is not "using EPS". But it still feeds the critical loads from the "EPS" connection as per Fig 1 which you evidently still do not know how to interpret correctly.

BTW do not be tempted to connect the ring mains, cooker or immersion heater circuits to the kettle. The sentence you have quoted is not intended to be read like that. /sarcasm

[sharpener]

Once "tripped" you have to then shut the unit down - disconnect batteries and PV - and restart it to get power back.

Just what you want to be doing in a blackout!