|
|
Post by tytower on Jan 24, 2017 7:54:14 GMT
I'm about to connect up my new panels in two strings of six each. I didn't have a fuse in case of massive surge of current previously so I have installed a 125 amp fuse on the positive lines . I was told this if fine for protection and no inter-exchange can occur between the string circuits . I wondered what the forum thought of this ? I have tried each string separately and all is fine off course and am just about to try it with both strings connected to the inverter . Just a case of last moment jitters in case this is not what was meant to be done . Anyone know for sure? Anyone doing this atm?  |
|
|
|
Post by dennis461 on Jan 24, 2017 15:30:54 GMT
First, 125 amp fuse seems way too big, panels probably put out 20-30 amps max (guessing since there are no part numbers identified).
Are the two strings going to the same input terminals of inverter (does the inverter have two or four terminal screws?)
Make sure you don't mix up positive and negative :-)
|
|
|
|
Post by tytower on Jan 24, 2017 16:49:08 GMT
Thanks dennis . Yes I think the intention is a lightning protector.The panels would be toast but perhaps the grid tied inverter would survive.The inverter has 4 terminals for two separate strings . Its stated output is 7 amps per panel so string output is only 7 amps @ 240V DC max. So the entiere system would only have 14 amps @ 240V DC max .
Its possible however the supplied fuse is to be put between inverter and powerco line. The kit does not say.Our sparky does not know it seems so thats why I'm checking . Even there it seems wildly oversized . Putting out 3000 watts max (240V x 14A ) AC so say 12 amps AC it sis madly excessive so I really don't know what other use it could have in the system?
|
|
usernameinvalid
New Member
Even if you're on the right track if you stand still you'll get run over.
Posts: 16 
|
Post by usernameinvalid on Jan 24, 2017 16:59:25 GMT
If you're grid tied contact the power company. They will know and will want to inspect your set up anyway before you power it up.
|
|
|
|
Post by tytower on Jan 25, 2017 23:22:14 GMT
If you're grid tied contact the power company. They will know and will want to inspect your set up anyway before you power it up. I don't know where you are situated but I can tell you on my island its DIY or nothing . You wait 3 weeks for an email back from the powerco on anything solar panel related . Just how it is!. Sparky came to the conclusion its in the powerco line connection so thats where it went. We will wait and see on that one . My thoughts became its a bit too big to do any good anywhere and there are better alternatives for system lightening protection between panels and inverter . Running the two positives together though is fine or the two negs might be a bit better as current build up would be on the negative line first , instantaneously speaking, so the charge would not exceed say 200 amps further down the line before it blew . They reckon its a fast blow fuse at least but I don't think there would be much left of the inverter. |
|
usernameinvalid
New Member
Even if you're on the right track if you stand still you'll get run over.
Posts: 16
|
Post by usernameinvalid on Jan 26, 2017 1:00:56 GMT
Where I live you need a contract with the power company. You can't just tie into the grid.
|
|
|
|
Post by tytower on Jan 27, 2017 10:32:53 GMT
See the problem with a lot of you people who get on these forums is you just make assumptions . Wrong assumptions mostly . Then you can't resist telling other people what to do or not to do ,more often because you then think you are right and no doubt righteous and holy .
Pull your heads in .
You have both made wrong assumptions .
There is no law that says I cannot do as I wish on my own systems . It is indeed illegal to hook up to the powerco grid without permission and electrical qualification.
There is also no requirement on me to fully explain what my intentions are to anyone and if I don't tell you its then none of your business is it . Why make assumptions
In fact working in conjunction with others I am designing and implementing a grid tied system which will be tied to my own grid so what do you know about that then huh? What do you know about UPS supplies and changing inverter boards to low frequency and high frequency to enable this to work and charge a battery bank too. What do you know of my qualifications .
Its just all wrongful assumption and an appology should be forthcomming if you wish to have any share in my progress.
Just exactly who ,do you think or claim to be speaking for, joanne ? we are not even in the same country, I'm half way around the world from you. Your rules have no bearing on anything I do.
|
|
usernameinvalid
New Member
Even if you're on the right track if you stand still you'll get run over.
Posts: 16
|
Post by usernameinvalid on Jan 27, 2017 16:47:55 GMT
I'm here to learn and help if I can.
Sorry to bother you it won't happen again.
|
|
|
|
Post by dennis461 on Jan 27, 2017 21:59:56 GMT
Everyone have a cold beer before posting....
As for fuses and lightning, it is no contest.
Lightning jumps large distances a cloud to earth, so a two inch fuse cannot stop a direct hit, nor can the inverter.
The lightning bolt will fry everything if it hits the solar panel.
(reminder to self, call homeowners insurance)
As for an electrician or power company wanting a fuse, no discussion needed, put it in if it is what they want.
tytower, you said your Sparky wanted it, so that's done.
Here in USA, New Jersey, the township electrical inspector never looked at my breaker panel, the power company never came to the house, the NJ BPU also waived their inspection.
I agree with tytower, we are on our own for the most part.
Enough for now, need to go get another beer.
|
|
|
|
Post by tytower on Jan 29, 2017 6:56:48 GMT
Mmm in fact it was supplied in a kit from the mainland for a rental house I have and both sparky and I , who regularly have a beer together as I trained him, could not decide on where it should go . It is a requirement on the mainland to go between inverter and powerco line it turns out but exactly why and what good it would do escapes me . he does heights , I do not. The lightening protection was just a throw around.
The interesting part that grabbed me was both of the positives going through the same fuse.
If you think about it ,
Take two 6 volt dc torches
Break the positive line of each and bring the two battery ends to a single fuse and then return the lines to the torches.
The current of each will travel through the same fuse and when both are on all the system current passes through it .There is no effect on either torch.
This simple scenario gave me trouble at my old age and needed thought .DC current fed to the inverter can likewise be thought of as a big tank of DC potential and phase differences do not apply . The inverter sucks from whichever string it wants depending on how its made.
|
|
Dave Simmo
Junior Member
Recovering from Surgery. Shoulders had to be rebuilt. End Stage joint damage
Posts: 76
|
Post by Dave Simmo on Jan 29, 2017 13:50:21 GMT
My 2 cents Dont tie into the Grid. Wire it separate for lights. Run separate wiring you and Low amps Lights is a Key and I know others wont agree but think 12 volts is the only way to go. Good luck and Hang in there. You can do this
|
|
