Growatt SPF5000ES Offgrid 9kw DIY Solar Project

[Pink7]

8 minutes ago, Encid said:

The estimate should be based on panel rating x 0.8 x 5 (80% of panel rating over 5 hours), so if you have 20 off 330W panels your average daily production would be 330 x 20 x 0.8 x 5 = 26.4 kW.

Thanks for the input. what i estimated was production/hour ( watthour) to see what would be capacity left for charge batteries.

 

Pink

[Muhendis]

5 hours ago, Crossy said:

 

Yes, but do ensure you place breakers and fuses where the installation manual says.

 

And don't forget surge/lightning protection

[Muhendis]

6 hours ago, BritManToo said:

Doesn't mean anything to me, battery storage is measured in kWhr.

Here is a 48V 8kWhr battery, 35kbht.

https://www.lazada.co.th//products/i2393934477-s8157207174.html

 

80-90% of Lifepo4 batteries are usable, nobody buys lead acid batteries any more.

Small point but the Lazada batteries you mention are not LiFePO4's. They are NMC's same as used in power tools.

[BritManToo]

41 minutes ago, Muhendis said:

Small point but the Lazada batteries you mention are not LiFePO4's. They are NMC's same as used in power tools.

Ok

Lithium batteries  .............. can use 80-90%

I didn't look to see what batteries he was putting in that particular pack.

It appears he's mostly using NMC at the moment.

Edited August 10, 2022 by BritManToo

[BritManToo]

50 minutes ago, Muhendis said:

And don't forget surge/lightning protection

Unless your home has a history of lightning strikes, why would you need that protection?

IMHO it's nothing but a little extra money in the solar scammers pockets.

(like the 'special' wires they want you to use).

 

Q: How many people have you encountered who had lightning strikes on their solar equipment?

A: None, same as me.

Edited August 10, 2022 by BritManToo

[Pink7]

24 minutes ago, BritManToo said:

Unless your home has a history of lightning strikes, why would you need that protection?

IMHO it's nothing but a little extra money in the solar scammers pockets.

(like the 'special' wires they want you to use).

 

Q: How many people have you encountered who had lightning strikes on their solar equipment?

A: None, same as me.

what wire u suggest for serial string panels?

 

Pink

[BritManToo]

9 minutes ago, Pink7 said:

what wire u suggest for serial string panels?

 

Pink

I plug all the mc4 connectors in series, then use 2.5mm insulated twin to connect through a double 500V DC breaker to the inverter. 

 

OK, so I should put the exterior twin insulated in an electrical conduit to protect the insulation from uv degradation, but I'm betting it's good for 5 years as is. 

Edited August 10, 2022 by BritManToo

[sezze]

9 hours ago, BritManToo said:

Unless your home has a history of lightning strikes, why would you need that protection?

IMHO it's nothing but a little extra money in the solar scammers pockets.

(like the 'special' wires they want you to use).

 

Q: How many people have you encountered who had lightning strikes on their solar equipment?

A: None, same as me.

Correct , however , there are lightning strikes on homes every single day , and i do know people who did have it . There was no solar installation there , but that is beside the point i think . Problem with solar is that there are high voltages , and they do keep on generating electricity even when the house is completely on fire ( many times dangerous for firefighters these days , as are the lithium batteries when there is a fire in them ) . Surge protectors are near the cheapest item in a solar installation , only a few 100 baht . For that price , why skip on it ? Taking a 50k to several 100k of installation and then let some extra safety let go for a few 100 baht ...  I am all in for saving some money but for that amount of money , i wouldn't skip it .

[Crossy]

9 hours ago, BritManToo said:

Q: How many people have you encountered who had lightning strikes on their solar equipment?

A: None, same as me.

 

Those arrestors won't save anything from a direct hit, it's induced surges from nearby strikes that you are protecting from.

 

By the way, you can add one known lightning/solar "hit".

 

After a particularly "busy" storm we awoke to a rather annoyed beeping from one of the inverters which was indicating "earth leakage".  One of the DC arrestors had gone sufficiently leaky to trigger the protection, one has to assume it had done its job.

 

How do you know you've not had any surges and have got away with it? Your inverters will also likely have at least some internal protection.

 

These beasts are cheap insurance, but like all insurance it's up-2-u.

 

EDIT It's worth noting that even in the UK (hardly the lightning capital of the world) surge suppression on the incoming supply is becoming de-rigeur, it's not mandated by the regulations, yet, (sparkies are supposed to do a risk-assessment).

[Muhendis]

1 hour ago, Crossy said:

 

Those arrestors won't save anything from a direct hit, it's induced surges from nearby strikes that you are protecting from.

 

By the way, you can add one known lightning/solar "hit".

 

After a particularly "busy" storm we awoke to a rather annoyed beeping from one of the inverters which was indicating "earth leakage".  One of the DC arrestors had gone sufficiently leaky to trigger the protection, one has to assume it had done its job.

 

How do you know you've not had any surges and have got away with it? Your inverters will also likely have at least some internal protection.

 

These beasts are cheap insurance, but like all insurance it's up-2-u.

 

EDIT It's worth noting that even in the UK (hardly the lightning capital of the world) surge suppression on the incoming supply is becoming de-rigeur, it's not mandated by the regulations, yet, (sparkies are supposed to do a risk-assessment).

An emp (electro magnetic pulse) from a nearby lightning strike came into my inverters via the overhead electric supply. Internal mov protection was not man enough in two of the three inverters and the ATS. The damage caused was significant and very expensive.

Lesson learnt and protection fitted.

Protection of the solar panel output is standard and always fitted in supplied combiner boxes.

The cost of fitting a protective device is a one off thing for a few hundred Baht whereas an insurance policy is usually ongoing. So I don't think of it as a scam.

[Pink7]

regarding:  surge/lightning protection: I have 2 serial strings so i guess i need 1 unit per string then?   

Edited August 11, 2022 by Pink7

[Pink7]

Any one have some good suggestions for this parts? Price vice Im looking for something midrange i guess.

 

2 x 600VDC/30A circuit breaker

2 surge protection

1 x AC breaker (32A?)

 

Pink

[MrJ2U]

Great price. 

 

Almost 5,000 baht on Lazada.

 

Good luck 

 

 

Edited August 11, 2022 by MrJ2U

[degrub]

Don’t forget surge protection (MOVs) on the AC feed to the property. Cheap insurance. Replace every decade or so or when the indicator light goes out.

[Pink7]

From Inverter manual:

 

WARNING: Because this inverter is non-isolated, only three types of PV modules are acceptable: single crystalline and poly crystalline with class A-rated and CIGS modules. To avoid any malfunction, do not connect any PV modules with possible current leakage to the inverter. For example, grounded PV modules will cause current leakage to the inverter. When using CIGS modules, please be sure NO grounding.

 

Means ?

 

Pink

[Crossy]

3 hours ago, Pink7 said:

From Inverter manual:

 

WARNING: Because this inverter is non-isolated, only three types of PV modules are acceptable: single crystalline and poly crystalline with class A-rated and CIGS modules. To avoid any malfunction, do not connect any PV modules with possible current leakage to the inverter. For example, grounded PV modules will cause current leakage to the inverter. When using CIGS modules, please be sure NO grounding.

 

Means ?

 

Pink

 

It means don't ground the + or - side of the panels, you should still ground the metalwork of course.

 

Also don't ground either pole of your battery, in fact don't gayly scatter grounds around, only ground terminals marked as "ground" or 

 

Grounded modules are rare these days anyway, any panel you buy will be just fine.

 

All high-frequency inverters have the same warning hidden somewhere in the dogumentation.

[Muhendis]

10 hours ago, Pink7 said:

regarding:  surge/lightning protection: I have 2 serial strings so i guess i need 1 unit per string then?   

Are the two serial strings joined into a single feed in a combiner box or are they two separate feeds into the solar inputs of an inverter?

If the former then only one is needed at the combiner output. If the latter then it's one per string.

Also please note that an AC anti surge/lightning protector is different from a DC one so get the right one for the job.

[Pink7]

2 hours ago, Crossy said:

 

It means don't ground the + or - side of the panels, you should still ground the metalwork of course.

 

Also don't ground either pole of your battery, in fact don't gayly scatter grounds around, only ground terminals marked as "ground" or 

 

Grounded modules are rare these days anyway, any panel you buy will be just fine.

 

All high-frequency inverters have the same warning hidden somewhere in the dogumentation.

Thanks for that info

 

Pink

[Pink7]

1 hour ago, Muhendis said:

Are the two serial strings joined into a single feed in a combiner box or are they two separate feeds into the solar inputs of an inverter?

If the former then only one is needed at the combiner output. If the latter then it's one per string.

Also please note that an AC anti surge/lightning protector is different from a DC one so get the right one for the job.

There is 2 single serial strings who have its own pw port on inverter. So i will use a dc breaker and dc surge/lightning protector between panels and inverter. AC anti surge/lightning protector i should use for grip power before inverter?

 

Pink

Edited August 12, 2022 by Pink7

[Pink7]

2 hours ago, Muhendis said:

Are the two serial strings joined into a single feed in a combiner box or are they two separate feeds into the solar inputs of an inverter?

If the former then only one is needed at the combiner output. If the latter then it's one per string.

Also please note that an AC anti surge/lightning protector is different from a DC one so get the right one for the job.

This one ok for ac?

 

 

Pink

[007 RED]

53 minutes ago, Pink7 said:

There is 2 single serial strings who have its own pw port on inverter. So i will use a dc breaker and dc surge/lightning protector between panels and inverter. AC anti surge/lightning protector i should use for grip power before inverter?

 

Pink

As has pointed out by @Muhendis and @Crossy, it is wise to have an appropriate breakers and surge suppressors located either side and as close to your inverter as practically possible.  As has been mentioned, it is extremely important to only use a DC breaker on the DC side of the inverter and an AC breaker on the AC side of the inverter.  Big flashes and magic smoke are likely to occur if you use an AC breaker on the DC side of the inverter.

 

The breakers enable you to isolate the inverter from DC and AC supplies, so that you can carry out any maintenance on the panels or remove the inverter if necessary.  The surge suppressors are there to protect your investment (inverter) in the event of a surge arising from a nearby lightening strike or problems with you local PEA supply.

 

The photo below which I provided in an earlier post shows my small scale set up with the Sofar GTI inverter in the centre. 

 

The cables coming down from the top left of the picture are the DC +/- feeds from the 4 x 415W (connected in series) solar panels mounted directly above on the roof of the car port.  These cables are connected to the DC breaker and and surge suppressor which are housed in my home made 'safety box' (small empty consumer unit box).  From the DC breaker the +/- cables are then connected to the respective input DC sockets on the inverter. 

 

With your proposed setup you would have two feeds coming from your solar panel array, e.g. PV1 and PV2, each of which should be connected to their own DC breakers and surge suppressors before being connected to the inlet connections on the inverter.

 

The large black plug and cable coming out the bottom right of my inverter is the AC cable which is feeding power generated by the inverter to my house consumer unit.  This cable is initially connected to the AC breaker and suppressor, again in a home made 'safety box' before being connected to the consumer unit in the house.

 

FYI.... Both 'safety boxes' and the inverter have separate earth cables which are connected to the metalwork of the car port.  The metalwork inside the main supports of the car port are buried quite deep " meters plus) into the ground, but I have also connected a 2 meter earth rod buried in the soil to the car port metalwork.  'Belt and braces' approach.

 

I hope this helps with your proposed project.

[Pink7]

36 minutes ago, 007 RED said:

As has pointed out by @Muhendis and @Crossy, it is wise to have an appropriate breakers and surge suppressors located either side and as close to your inverter as practically possible.  As has been mentioned, it is extremely important to only use a DC breaker on the DC side of the inverter and an AC breaker on the AC side of the inverter.  Big flashes and magic smoke are likely to occur if you use an AC breaker on the DC side of the inverter.

 

The breakers enable you to isolate the inverter from DC and AC supplies, so that you can carry out any maintenance on the panels or remove the inverter if necessary.  The surge suppressors are there to protect your investment (inverter) in the event of a surge arising from a nearby lightening strike or problems with you local PEA supply.

 

The photo below which I provided in an earlier post shows my small scale set up with the Sofar GTI inverter in the centre. 

 

The cables coming down from the top left of the picture are the DC +/- feeds from the 4 x 415W (connected in series) solar panels mounted directly above on the roof of the car port.  These cables are connected to the DC breaker and and surge suppressor which are housed in my home made 'safety box' (small empty consumer unit box).  From the DC breaker the +/- cables are then connected to the respective input DC sockets on the inverter. 

 

With your proposed setup you would have two feeds coming from your solar panel array, e.g. PV1 and PV2, each of which should be connected to their own DC breakers and surge suppressors before being connected to the inlet connections on the inverter.

 

The large black plug and cable coming out the bottom right of my inverter is the AC cable which is feeding power generated by the inverter to my house consumer unit.  This cable is initially connected to the AC breaker and suppressor, again in a home made 'safety box' before being connected to the consumer unit in the house.

 

FYI.... Both 'safety boxes' and the inverter have separate earth cables which are connected to the metalwork of the car port.  The metalwork inside the main supports of the car port are buried quite deep " meters plus) into the ground, but I have also connected a 2 meter earth rod buried in the soil to the car port metalwork.  'Belt and braces' approach.

 

I hope this helps with your proposed project.

Thanks for the info. Your setup is connected to grid? My manual want breaker and surge protection on the IN power sources, grid and pw.

 

Pink

[Crossy]

5 minutes ago, Pink7 said:

Thanks for the info. Your setup is connected to grid? My manual want breaker and surge protection on the IN power sources, grid and pw.

 

It's a grid-tie inverter so there's no "out" connection.

 

Your manual is correct ???? 

[Muhendis]

2 hours ago, Pink7 said:

There is 2 single serial strings who have its own pw port on inverter. So i will use a dc breaker and dc surge/lightning protector between panels and inverter. AC anti surge/lightning protector i should use for grip power before inverter?

 

Pink

The incoming AC utility supply will connect to a fused isolator switch with the output from the fused isolator switch going to your inverter. The AC lightning/surge protector connects at the output from the fused isolator switch. The surge protector will go low resistance if there is a spike/surge in the mains voltage. This low resistance will cause a large current to flow through the fused isolator switch which will trip and save all other bits'n pieces  connected to the incoming utility supply.

Edited August 12, 2022 by Muhendis

[Pink7]

3 minutes ago, Muhendis said:

The AC utility input will connect to a fused isolator switch with the output from the fused isolator switch going to your inverter. The AC lightning/surge protector connects at the output from the fused isolator switch. The surge protector will go low resistance if there is a spike/surge in the mains voltage. This low resistance will cause a large current to flow through the fused isolator switch which will trip and save all other bits'n pieces  connected to the incoming utility supply.

Ok, can you show example of what i need to buy for that?

 

Pink

[Muhendis]

13 minutes ago, Pink7 said:

Ok, can you show example of what i need to buy for that?

 

Pink

Here's my scruffy old protector. Anything like this will do.

[Pink7]

6 minutes ago, Muhendis said:

Here's my scruffy old protector. Anything like this will do.

Ok, the one i posted earlier is ok?

[Muhendis]

7 minutes ago, Pink7 said:

Ok, the one i posted earlier is ok?

Yes

[Pink7]

1 minute ago, Muhendis said:

Yes

Great, who of the 3 would you choose?

 

Pink

[Pink7]

39 minutes ago, Muhendis said:

Yes

And this?

 

Pink