Panel requirements for grid tie in for 10k watt system

[dschmidt@unitizing]

Thanks, I looked that lug up. I can`t find a good picture of how it works but it must work similar to the other one.

You have been a big help, so I have another question concerning the correct size of the fused disconnect if I install an array between 12.5 and 14k. Would I need a larger than the 60 amp disconnect?

Thanks, dave

The correct Ilsco is IPC 4/0-#6 which is about $8 to $12 Much smaller than the one you selected.

With a 10k inverter you want to use a 60A Disconnect with 60A fuses. Even though the wire may be rated at 65A you don't need use a disconnect of similar rating. It goes the other way, for service rated equipment the wire must be at least arry the maximum fuse size of the disocnnect.

Small disconnects are rated 30,60,100 & 200A Each size uses a different physical fuse size fuse. While you can use smaller fuses in a disconnect, they usually require an adapter.

Andy

[sensij]

Thanks, I looked that lug up. I can`t find a good picture of how it works but it must work similar to the other one.

You have been a big help, so I have another question concerning the correct size of the fused disconnect if I install an array between 12.5 and 14k. Would I need a larger than the 60 amp disconnect?

Thanks, dave

If your inverter (or inverters) total around 11.5 kW or less, 60 A will probably be OK. More than that, and you bump to the next size up.

[PVAndy]

If your inverter (or inverters) total around 11.5 kW or less, 60 A will probably be OK. More than that, and you bump to the next size up.

Seems to be a little reason to why SolarEdge & Fronius have 11.4 kW Inverters and SMA tops out in small single phase at 11 kW.
The OP in this case has a 10kw inverter

Andy

[dschmidt@unitizing]

You been very helpful. I think I have most everything figured out with a few puzzling pieces that I need to figure out. If you be so kind to give me input on these I would appreciate it.

1. If I am planning on a solar array with somewhere between 12.5 an 14k, would I be better to use one inverter or 2. Or since I am more than 11.4 on the array would I be forced to use 2 inverters anyway.

2. Would you recommend to place the inverter(s) closer to the solar array or closer to the service panel I will be tying into, its approx 75-100 feet between the 2.

If your inverter (or inverters) total around 11.5 kW or less, 60 A will probably be OK. More than that, and you bump to the next size up.

[inetdog]

You been very helpful. I think I have most everything figured out with a few puzzling pieces that I need to figure out. If you be so kind to give me input on these I would appreciate it.

1. If I am planning on a solar array with somewhere between 12.5 an 14k, would I be better to use one inverter or 2. Or since I am more than 11.4 on the array would I be forced to use 2 inverters anyway.

2. Would you recommend to place the inverter(s) closer to the solar array or closer to the service panel I will be tying into, its approx 75-100 feet between the 2.

1. Yes, you will almost certainly need to go to two inverters if you really need that full power output.

2. It depends on the environment you want to put the inverters in, as well as what your DC voltage from the array will be.
If you will be running 240V AC, then go with the longer AC run unless your array voltage is 240V or higher. To minimize power loss for the same sized wire you make the longer run at the higher voltage. But for 75-100 feet you can just as well go with larger wire.
So do whatever makes the system easiest to maintain.

[PVAndy]

1. Yes, you will almost certainly need to go to two inverters if you really need that full power output.

2. It depends on the environment you want to put the inverters in, as well as what your DC voltage from the array will be.
If you will be running 240V AC, then go with the longer AC run unless your array voltage is 240V or higher. To minimize power loss for the same sized wire you make the longer run at the higher voltage. But for 75-100 feet you can just as well go with larger wire.
So do whatever makes the system easiest to maintain.

If I was running a DC are a size 14 kW I'd go with the 11.4 kW inverter. That gives you a DC to AC ratio of about 1.22 which is very acceptable

Of coarse you have to make sure the number of panels you are using is compatible with the Solaedge stringing for that inverter

Comments regarding having to match the DC to AC size the one-to-one are or just plain wrong to achieve maximum output

I know you're talking SolarEdge Invertrr using a pair of Sonny Boy 6000 TL – US – 22. Unless you have some shading issues to deal with. The Sunn Boys will start earlier in the morning and run later in the afternoon because they have a very low start voltage and low operating voltage

On my personal system and I have the choice of any products on the market I went with to 6000 Sunnyboys. Having a pair of 1500 W 120 V secure power supply outlets is very handy

The Lisco lug just clamps on to the 4/0 main service line and you slip the unsterile do end of the number six into the other side and then tighten it with a 7:16 wrench

Also just be advised that it connects for over 10 kW systems are quite often more difficult than under 10 kW system depending on utility


Regarding voltage drop I always try to mount the inverters is close to the array simply because they were typically many more wires involved if you were to use an 11.4 kg why inverter the operating current add max power output is slightly below 50 A so the voltage drop on 100 foot run is about 4.7 V or 1.9%. Safely below the 3% voltage drop typically used as a design criteria.


Andy

[bcroe]

1. If I am planning on a solar array with somewhere
between 12.5 an 14k, would I be better to use one inverter or 2.

If you can divide your system into 2 identical halves, 2 inverters have some advantages.
Without shading, just a glance for checking operation will tell if the halves match. But
it will double up disconnects, breakers, etc. Bruce Roe

[Elu951]

If you can divide your system into 2 identical halves, 2 inverters have some advantages.
Without shading, just a glance for checking operation will tell if the halves match. But
it will double up disconnects, breakers, etc. Bruce Roe

I'm making a similar set up,so if I'm installing 2 inverters, do I interconnect both to the line side of the service with separate lugs on the same conductor?

[foo1bar]

I'm making a similar set up,so if I'm installing 2 inverters, do I interconnect both to the line side of the service with separate lugs on the same conductor?

You should probably start your own thread rather than use this almost 2 year old thread.

But if you have 2 inverters most likely you're going to have a breaker box where the two (or more) inverters are combined. Then the single cable from that solar-only subpanel goes on to your main breaker panel. (Or to the line-side tap if you have to do that method and are allowed to do that method)
Each individual wire connected to the inverter should have the other end directly connected to a breaker - there shouldn't be two inverters that are connected directly to a single breaker. (micro-inverters would be the exception to that- but you're not talking microinverters)

Your electrician should have a wiring diagram of what he'll be doing as part of his permit application. (And if you're DIY'ing this, you need to draw up the wiring diagram as part of your permit application)

[bcroe]

That is true here, except there is an AC disconnect switch between each inverter and its circuit breaker.
Bruce Roe

[Elu951]

Sorry, couldn't figuer out how to make a new post.
So we are doing 3 SB7.0 on a 240 service with a 200amp main breaker. I'm thinking of setting up a dedicated panel for the solar breakers and do a line side tap. What's the best way to size the type of service panel to install and wire to the main service between the meter and the 200amp breaker?

[foo1bar]

click on 'Solar Panels for your Home, Grid Tied Solar PV' at the top.
then '+ New Topic'

I haven't done a line side tap. I'd think the way to size the breaker panel is to figure out what's going to be on it and make sure it's capable of that many amps.