enphase micro inverters

[marc8]

hi all

just need some advice on the 3 strings on micro inverters

4 panels on one string east
6 panels on another string west
4 panels on south string ground floor roof


do they do a junction box for multiple connections & then onto monotiring station?

also this would be my job for MCS approval would this go down using this system anyone used micro inverters?

any help would be apperciated?

was going to use multi string inverter but was told that this would not give me the best mppt
using the 10 panels over east & west as the closet inverter would be 3kva multi string unit & best i could get would
be 2.5kw-2.85kw total for output using the 10 panels, was only adding the extra 4 panels if i use micro inverters.

hope the above makes sense

 

[spidersparks]

When we do a system like what your describing we put wiska boxes on the tails coming through the roof then screw them to the rafters, then link all three together with 6mm t+e with one 6mm back to the rotary isolator near the dist. board hope this helps
David

 

[Worcester]

When we do micro inverters we put a double pole rotary isolator in the roof for each "string".

Personally we would run each "string" to a small CU so that each final circuit is on its own MCB via the main switch in the small CU which can act as your double pole isolator, to the Generation meter, then another double pole MCB to either the existing CU or henley'd in between the DNO meter and the CU.

How are they supposed to communicate to the base / monitoring unit? Wireless? Zigbee? Bluetooth? - remember you may need to power that as well.

p.s. you could have done it with SolarEdge optimisers and one inverter

 

[jason121]

Enphase are wireless to the gateway unit. A lot better than the Enecsys system to install. No repeater to install

 

[marc8]

hi many thanks to you both for response will have a look solar edge optimisers but sure will be ok
just how was thinking of the comms side of things with regard to monitoring the whole system.

cheers

 

[MCS Renewables]

We do it the same as spider sparks above .

Enphase M215 inverters connect to the gateway through the electricity cable. You need to install a twin socket for the gateway . We do it with a sub board with two 16A RCBO's. one for the PV and one for the twin socket.
The gateway plugs in and so does one of the bridging plugs for the internet. The other bridging plug goes near the internet hub.


Forget Solar-edge it's not anything like as good as Enphase. In our test set ups, both 2kW identical systems on a barn roof the Enphase micro starts earlier, finishes later and is at least 5% better every day. The solar edge has one point of failure and requires DC cabling which is usually high voltage and could be an issue for firemen etc in the future. The solar edge needs a large space for the inverter.



Having no high voltage DC cabling in the project has made Enphase an easy sale for schools and other similar projects.


You get what you pay for ...
on eBay you can buy a solar edge plastic optimiser for £30 or an Enphase solid metal micro inverter for £90
I know which one I think will last 20 years on a roof !

 

[marc8]

Hi all thanks for the advice

made up mind now going to with enphase although more money seems like a better job

will set out strings with 6mm going to pick up each string inside loft, except low level roof
i will drop down 6mm in conduit & connect cable in wiska box then connect back in main loft in 6mm. connect all together in parallel then go onto consumer unit with double socket
for comms.
max lenght of run for furthest string including the enphase branch cable is probably going to be about 30meters.
just to clarify a couple of things noticed in video each enphase unit is earhted could i earth the
rail as i see the enphase unit is bolted to the rail or would you recommend each unit?
also i take it that the comms side is like the old X10 system using Hz down the cable?
also looking to buy kit on tuesday next week through natural sparx (senate) anyone have any other pv suppliers offering good deals on these?
thanks for help

 

[Worcester]

Natural Sparx is part of Rexel, their prices tend to be good, their deliveries less so....... On two jobs, both times product turned up late.. so aim to have it delivered a week before you need it, to make sure all the bits are in the box.

 

[MCS Renewables]

You could try either of these stockists for a quote :-

Solar Photovoltaic Panels Ipswich based

Metgen - Solar Photovolatics Wholesaler | Solar PV & Renewable Energy Trade Supplier | Metgen, UK near Southampton

used both with no problems.

or on Enphase page there are a list of other alternatives :-

How to Buy | Enphase UK

 

[Worcester]

We've had good deals with CJ Solar, they also trade as Solar Trade Sales (same Co) https://www.solartradesales.co.uk/index
And Metgen have had good prices too.

Not YET been let down by either of them.

 

[whinmoor]

Yes, Metgen were good when we dealt with them.

 

[marc8]

hi many thanks for all advice am taking on board great help just finished measures for roof structure
& wind calcs to be sent off cheers