DC or AC cable run from 2nd array

[PV Rob]

Hello

I am fitting to solar arrays, on on my main roof 4.5kWh and one on my office roof 3kWh, my office is at the end of my garden around 50 meters from the main inverter a GivEnergy 5kWh hybrid inverter with a 8.2kWh battery, connected to the main house distribution board.
The main distribution board currently feeds the office with 2.5mm 3 core cable.
Should I get an inverter in the office / or run DC cabling to the main inverter?

 

[PV Rob]

 

[Hedges]

You can connect two PV arrays in parallel and feed a single inverter or SCC if the arrays have same voltage (number of panels in series.)
This can be beneficial if the arrays are oriented differently, so their peak production is at different times of day; they will share use of lower wattage electronics.
If your device has multiple MPPT inputs, different voltage arrays could go to that.
Have to look at PV current specs of it.

4.5kW + 3kW = 7.5 kW. If your hybrid is rated 5kW maximum AC output or maximum charge power, then combining the two arrays might exceed it's capability. Usually that is allowed, but the extra available power in middle of the day would be wasted. If the two arrays are at different angles so peak production (area present to sun) is about 5kW, then it could be a good fit. Otherwise, using an additional inverter might be best to capture all the power.

GivEnergy Giv-HY5.0 5kW Hybrid Solar Inverter

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"Inverter has 2 MPPT PV inputs that allow you to have solar panels in 2 different orientations"
"Inverter do have 2500W backup power capability"

Don't know about your market, but here in the US we have some models such as Sol Ark which have their own wattage rating and can manage additional grid-tie inverters connected to them. On-grid the extra power is passed through a relay. Off-grid, the inverter can vary frequency to adjust power output of the grid-tie inverters.

But you're planning on a more modest 2500W battery backup; if that is sufficient then using a separate inverter would be the simple way to have more total grid-tie PV.

 

[PV Rob]

Here are the specs for the inverter I am planning on using... I am leaning toward running DV from the office to this main inverter. Just need to size up the DC cables...

 

[Hedges]

"Max DC Power 6.5 kWp"
You're planning to be a bit over that at 7.5 kW, not necessarily a problem.
If two orientations, even better (lower peak).
Two MPPT is good, handles two lengths.

11A maximum current per MPPT can handle.
Plan out PV array series/parallel configuration, see what fits the voltage and current limits. Including adjustment for record cold temperature.
Many panels are over 5.5A, so could only have one string not two in parallel.

 

[PV Rob]

"Max DC Power 6.5 kWp"
You're planning to be a bit over that at 7.5 kW, not necessarily a problem.
If two orientations, even better (lower peak).
Two MPPT is good, handles two lengths.

11A maximum current per MPPT can handle.
Plan out PV array series/parallel configuration, see what fits the voltage and current limits. Including adjustment for record cold temperature.
Many panels are over 5.5A, so could only have one string not two in parallel.

Awesome.. thanks so much.