Sunsynk 8kw new installation

[lancelot 5]

Just installed a Sunsynk 8kw inverter DIY and want to share some info.

We use about 1000kwh (units) per month in our house so about 33 per day with about half in the day and half after PV hours. This is about average for a family home I recon in SA.

Already have 2 Solar geysers, gas plates and all lights LED.

I wanted to be independent from the grid as much as possible which weighed heavier than economics although my return is still acceptable and higher after tax than any risk free investment. The whole house runs through the inverter including oven, the solar geyser AC elements, all plugs etc. Only the 4 Aircons is supplied before the inverter but with the Sunsynk CT which fit over the supply line the inverter will push electricity to them too if sufficient PV and battery power are available. I have one normal plug before inverter for if I have to weld or use heavy machinery.

I Installed:

Sunsynk 8kw  Brilliant inverter easy to do DIY and with help from Powerforum posts.

Jinko Mono Cheetah 400w panels * 18 - Connected in 2 series - 9 each. 9 panels in series match perfectly, max voltage around 410V real life in October (Sunsynk specs max 450V) and producing 97% of rated panel watts (3500w per string) max.  Fitted on aluminium rails on tile roof. Fitting the brackets under tiles is quite a job got my son to do that. 6mm PV cable running in PVC conduit from panels to inverter.

One set is facing West and the other facing North. I think if you can get East and west facing panels that is ideal, as you need PV power early in the morning to charge low batteries and then you want to produce as late as possible in the afternoon to have full batteries going into evening. Although not the ideal orientation PV panels are cheaper than additional batteries.

Pylontech US3000 * 5 These batteries when 100% charged at 5pm run the whole house through the night (have about 20 outside lights 3 pc's etc) and start to charge at 6am from west panels on around 30% SOC in October.

By 11:30 am the batteries are normally 100% charged, then I boost the geysers through Geyserwise on free electricity to increase their temperature so that they are still warm in the morning.

PV protection DB with fuses, surge arrestors and DC isolators.

Fuse and isolator between Batteries and Inverter

Grounding ROD and all earth wiring.

AC CB and change over switch etc in AC DB with relay for earth neutral bond

 

Total cost about R 210 000 (ex own labour) except for heavy overcast days I am not using any power from Tshwane, bill was about R1800-R2000 per month.

The feeling when the kettle and iron etc are on during the day and you know that it is not costing you anything (yes i know it is kinda) is priceless.

 

 

 

Edited Friday at 10:16 by lancelot

[Bloubul7 38]

Well done on a very neat system.

I must agree these Sunsynk units are awesome.  I recently upgraded from an Axpert King to a Sunsynk 8.8kw unit. On the Axpert the best efficiency I could get from the panels were 70% however with the Sunsynk my average efficiency has increased to 89% of the rated power.  This is a massive increase and well worth the paying extra for the inverter

[Bobster 139]

2 hours ago, lancelot said:

Total cost about R 210 000 (ex own labour) except for heavy overcast days I am not using any power from Tshwane, bill was about R1800-R2000 per month.

The feeling when the kettle and iron etc are on during the day and you know that it is not costing you anything (yes i know it is kinda) is priceless.

This interests me, and makes me jealous, because I have NEVER had an entirely free day with my system. It draws a little from the grid every day - even though in theory, on a clear day like today, the system can power the entire property.

But congratulations on how well your system is working and on a nice, neat installation.

In what direction do the two strings face?  (Doh! Should have read before I clicked)

Edited Friday at 12:42 by Bobster
doh!

[lancelot 5]

I have a Conlog smart meter that will trip if I sent power back (it will kill me to import 100w to prevent this)  so for now I have simply switched off the municipal supply until I get a token to allow a little feedback. Makes for a little monitoring on the SOC of the batteries.

[Achmat 19]

Nicely done. 

My install came to about R200k and have been generating +50kwh these past 5 days in CT. 

Only have 3 x 3.5kw pylontech batteries and also need to increase it to 5 to get me through a full night. 

I have 3 strings. 11 x 305w on 2 strings on MPPT 2 and 6 x 305w on 1 string in MPPT 1.

The inverter cannot log more than 50kwh but will not stop production. They are working on increasing the D display firmware to resolve this. 

On track for 6 consecutive days of 50kwh. 

Grid usage has dropped from 1 200kwh to 200kwh for the past month. 

[lancelot 5]

+50kwh per day is impressive, and that on 8540kw panels. On my solar calculator for Cape Town you are as close to maximum as can be. I assume your panels tilt and azimuth are near optimum.

Edited Saturday at 06:08 by lancelot

[Achmat 19]

17 minutes ago, lancelot said:

+50kwh per day is impressive, and that on 8540kw panels. On my solar calculator for Cape Town you are as close to maximum as can be. I assume your panels tilt and azimuth are near optimum.

I wish they were. 

It's almost flat mounted(5°) on my carport facing NW. 

I oversized my array due to not having it mounted in the ideal direction and inclination so I am just as surprised as anyone else at the amount of pv generation. 

[Muchachos 4]

On 2020/10/16 at 12:06 PM, lancelot said:

 

Nice system.

Edited Monday at 04:52 by Muchachos