New PV system

[user 35958]

Hi I've not had solar before but I've just ordered a 6KW system with a Fox 10KW battery system along with the fox 3-6kw hybrid inverter.
My question is further down the line I want to add a solar diverter as I have a tank and immersion heater ( using oil ). I'm swaying towards the My eddie as the build quality looks better than the others.

I'm worried about this discharging the battery. With 2 CTs at the consumer unit how will the eddie know when to start diverting power if the battery is doing the same thing?

Obviously I don't want to use battery power to heat my water. I would like it to either change the battery or the heat water. What is best way round Battery first or hot water first.
Is it possible to have both running together / has anyone got this setup?

Thanks in advance Dave

 

[johnb2713]

Hi I've not had solar before but I've just ordered a 6KW system with a Fox 10KW battery system along with the fox 3-6kw hybrid inverter.

Assuming the the inverter is 3.6kW, I suggest you contact the supplier and get a quote for a 6kW minimum inverter. Installers often suggest 3.6 kW because thats the maximum export you can do without additional paperwork with your DNO. The problem is, you only have switch a couple items on and you will be drawing power from the grid eg oven and one ring on the hob.

My question is further down the line I want to add a solar diverter as I have a tank and immersion heater ( using oil ). I'm swaying towards the My eddie as the build quality looks better than the others.

EDDI is a well designed robust unit thats very easy to setup.

I'm worried about this discharging the battery. With 2 CTs at the consumer unit how will the eddie know when to start diverting power if the battery is doing the same thing?

On my system theres a CT on the inverter output and a CT on the meter tails. If the inverter is exporting and the battery isnt fully charged it will increase the charge current to the battery thereby removing the export. Once the battery is full and there is an excess of energy available it will then start to export, thats when MyEnergi EDDI and my case ZAPPI spring into life, they start to divert the excess energy to hot water of EV as configured, the whole system works really well.

Obviously I don't want to use battery power to heat my water. I would like it to either change the battery or the heat water. What is best way round Battery first or hot water first.
Is it possible to have both running together / has anyone got this setup?

Yes I have this setup (except mine is a Growatt Inverter and Battery) and you can prioritise in the PV setup whether export or battery charging is priority and then it will all work as above.

 

[user 35958]

Thanks for your reply John ill order a second CT for the inverter ( good tip ) and ill speak to them about the inverter.

 

[user 35958]

Assuming the the inverter is 3.6kW, I suggest you contact the supplier and get a quote for a 6kW minimum inverter. Installers often suggest 3.6 kW because thats the maximum export you can do without additional paperwork with your DNO. The problem is, you only have switch a couple items on and you will be drawing power from the grid eg oven and one ring on the hob.


EDDI is a well designed robust unit thats very easy to setup.


On my system theres a CT on the inverter output and a CT on the meter tails. If the inverter is exporting and the battery isnt fully charged it will increase the charge current to the battery thereby removing the export. Once the battery is full and there is an excess of energy available it will then start to export, thats when MyEnergi EDDI and my case ZAPPI spring into life, they start to divert the excess energy to hot water of EV as configured, the whole system works really well.

Yes I have this setup (except mine is a Growatt Inverter and Battery) and you can prioritise in the PV setup whether export or battery charging is priority and then it will all work as above.

Thanks John the boys have been here today wiring it all up although they will have to return to do the panels! So from the Eddie CT1 goes to the meter tails next to the one from the Inverter that's seems right. CT2 from the Eddie they have wired into the inverter but I'm not sure this is right as you said it goes to inverter output problem is inverter output is twin and earth 5mm so I cant clamp onto just the live, if you know what I mean? And its a flat cable not round like the tails. Any chance you could send a picture of yours?

Thanks Dave

 

[johnb2713]

Thanks John the boys have been here today wiring it all up although they will have to return to do the panels! So from the Eddie CT1 goes to the meter tails next to the one from the Inverter that's seems right. CT2 from the Eddie they have wired into the inverter but I'm not sure this is right as you said it goes to inverter output problem is inverter output is twin and earth 5mm so I cant clamp onto just the live, if you know what I mean? And its a flat cable not round like the tails. Any chance you could send a picture of yours?

Thanks Dave

Mine is done wirelessly via HARVI to the EDDI unit. Heres what it looks like in the meter cabinet (not pretty ).The grey cable from the top that goes into the Harvi box is a CT on the inverter supply cable and the CT on the meter tail is the one that is shared by EDDI and ZAPPI via HARVI.

 

[user 35958]

Thanks for the picture John mine is the same except hard wired to the Eddie. Its the second CT at the Inverter i was worried about this is to stop my battery being discharged to heat water I only want it to divert excess power to water heater once my batteries are full ie use excess power only not battery power.

Dave

 

[johnb2713]

Thanks for the picture John mine is the same except hard wired to the Eddie. Its the second CT at the Inverter i was worried about this is to stop my battery being discharged to heat water I only want it to divert excess power to water heater once my batteries are full ie use excess power only not battery power.

Dave

The inverter will charge the batteries with as much solar that it has available, it doesnt need any CT's for that.
When the inverter is running it will monitor the CT and if it see's import taking place it will increase it's output voltage until the import ceases. Export the opposite occurs. If it sees more solar PV than is needed for balancing house loads it will then charge batteries by increasing the voltage on the charger output until such time everything is balanced i.e. all of the solar PV energy is being used.
Once the batteries are fully charged and there is spare energy available it will increase it's output voltage starting export of power. EDDI will see that and ramp up it's output into the immersion heater until the import / export is zero. This continues until the thermostat on the immersion opens then export resumes again.
While all of this is going on the inverter is still monitoring the CT and ramping up / down it's voltage in response to import & export.

 

[user 35958]

Thanks John I understand and have made the modification thanks for your help much appreciated