EG4 6000XP max PV idle voltage

[johnbrutovsky@hotmail.]

I currently have a EG4 6000EX with a max PV input voltage spec of 500 VOC. I set of my panels so that I have an open circuit voltage of 475 and a working voltage around 385. I'm thinking of taking advantage of the Signature Solar upgrade program and trading the EG4 6000EX for the XP. I noticed that the max VOC for PV input on that is slightly lower at 480 VOC. Do you think that I'll be okay keeping it that way on the EG4 6000XP where I am so close to the 480 spec?

 

[sunshine_eggo]

I currently have a EG4 6000EX with a max PV input voltage spec of 500 VOC. I set of my panels so that I have an open circuit voltage of 475 and a working voltage around 385. I'm thinking of taking advantage of the Signature Solar upgrade program and trading the EG4 6000EX for the XP. I noticed that the max VOC for PV input on that is slightly lower at 480 VOC. Do you think that I'll be okay keeping it that way on the EG4 6000XP where I am so close to the 480 spec?

WAY too high. Even in Maricopa, you have the potential to see near freezing temperatures. You must factor in what happens when panels see colder than 25°C cell temps... they output HIGHER voltage than spec.

Take at least one panel off the string.

 

[johnbrutovsky@hotmail.]

WAY too high. Even in Maricopa, you have the potential to see near freezing temperatures. You must factor in what happens when panels see colder than 25°C cell temps... they output HIGHER voltage than spec.

Take at least one panel off the string.

Say it tickles the 480 VOC , will the unit be damaged, or just generate a code and shut down?

 

[sunshine_eggo]

Say it tickles the 480 VOC , will the unit be damaged, or just generate a code and shut down?

This is the question of someone who doesn't give a shit about the ratings of equipment and hasn't bothered to educate themselves on proper system design.

What will happen? Something between nothing and complete destruction of the MPPT and voiding of the warranty.

Stop screwing around. I don't like telling people what to do just for fun. Don't believe me?

NEC says:



At 32-40°F, which you can easily see in Maricopa, you need AT LEAST a 10% safety margin on your max Voc, so 500V/1.1 = 454V

Absolutely, positively do not have a string Voc above 454V. Period.

 

[Luxpower_Gilbert]

Say it tickles the 480 VOC , will the unit be damaged, or just generate a code and shut down?

it will set an error or burn the mppt board.... i recommend keep the VOC 400V and below

 

[johnbrutovsky@hotmail.]

This is the question of someone who doesn't give a shit about the ratings of equipment and hasn't bothered to educate themselves on proper system design.

What will happen? Something between nothing and complete destruction of the MPPT and voiding of the warranty.

Stop screwing around. I don't like telling people what to do just for fun. Don't believe me?

NEC says:

View attachment 208810

At 32-40°F, which you can easily see in Maricopa, you need AT LEAST a 10% safety margin on your max Voc, so 500V/1.1 = 454V

Absolutely, positively do not have a string Voc above 454V. Period.

Thanks for the information. A bit harsh, but appreciated all the same. I'll be shifting one panel from a string to a different string to bring the VOC down a bit. While I get the cold temperatures are an important concern, it does seem really distant when I'm running my A/C unit 9 months a year. I was more concerned about the heat damaging the panels then the cold bumping up the VOC. I have learned something new. I was actually playing with an idea to create a watering system with PVC pipes mounted over the panels to keep them cooler when it's 118+ degrees outside. It'd be easy to do with a sprinkler timer, but I ultimately decided not to do that because I didn't want to temperature shock the panels ( even though the water would easily be way over 100 degrees by the time that it got to the roof. ( all water is hot during the heat of the summer, we actually turn off the water heater and use it to store cold water during the summer months ) , and I didn't like the idea of mineral build up on the panels from the crappy water that we have.

 

[johnbrutovsky@hotmail.]

it will set an error or burn the mppt board.... i recommend keep the VOC 400V and below

If the spec is 480 VOC, what is the reason for keeping the VOC below 400? I understand having a safety margin, but an 80 volt safety margin seems excessive. Have you seen problems going over 400 VOC? I'm trying to keep the system voltage as high as I safely can to cut down on the current that the wiring carries.

 

[EG4_Jared]

I currently have a EG4 6000EX with a max PV input voltage spec of 500 VOC. I set of my panels so that I have an open circuit voltage of 475 and a working voltage around 385. I'm thinking of taking advantage of the Signature Solar upgrade program and trading the EG4 6000EX for the XP. I noticed that the max VOC for PV input on that is slightly lower at 480 VOC. Do you think that I'll be okay keeping it that way on the EG4 6000XP where I am so close to the 480 spec?

How many panels do you currently have and the specs of the panels?

 

[Luxpower_Gilbert]

If the spec is 480 VOC, what is the reason for keeping the VOC below 400? I understand having a safety margin, but an 80 volt safety margin seems excessive. Have you seen problems going over 400 VOC? I'm trying to keep the system voltage as high as I safely can to cut down on the current that the wiring carries.

You have also considered the mppt range 100-380v. Imo its better to be safe than regret later…

 

[Dagoth Ur Does Solar]

If the spec is 480 VOC, what is the reason for keeping the VOC below 400?

Well, disregarding working voltage on the MPPT: if you do keep your string under 400 Voc, you're insulated against extremely cold freak weather potentially blowing your MPPT. At least, according to the NEC table @sunshine_eggo posted.

If I'm spending a bunch of money on a system, I'd rather be safe than sorry.

 

[johnbrutovsky@hotmail.]

How many panels do you currently have and the specs of th

I'll have to get back to you on that over the weekend. I'll been doing this system a little at a time. All panels are used. First year I put up 14 panels ( two strings of 7) ( they were around 37 volts each , maybe 230 - 250 watts ) with a Growatt 3000 system. Second year I replaced the Growatt with a the EG4 6000ex and added I think another 8 panels. Then this past winter I replaced one of the original 14 panels and added 5 400 watt panels. The first year was just a proof of concept to myself. I bought dirt cheap panels ( like $45 each ) that had cracks in the backing. Second year I bought slightly better panels, and the third year I bought slightly used in good condition panels. Really happy with the last batch I bought. ( over 400 watts each ) but they have a open circuit voltage in the 80 volt range. I can get you exact number after I get up on the roof and remind myslef what I bought.