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Confusing EG4 6500 VOC max Limit.

J7now

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Good morning. I have an EG4 6500 inverter. The inverter manual says it has a 500v max PV VOC power limit. I am confused whether this refers to the inverter just one side (channel) of the inverter: PV1 or both sides of the inverter: PV1+PV2? Which in turn would add up to 1000 and not 500 max VOC. The inverter manual is not very clear about this. Although it seems to suggest the total VOC is 1000. Please help.

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500 volts max per mppt controller. That isn't 1000 volts. Thats 500 volts on each one.

Also it won't use over 450 since thats the max mppt range. I wouldn't go over 450 to play it safe for cold weather peaks.
 
500 volts max per mppt controller. That isn't 1000 volts. Thats 500 volts on each one.

Also it won't use over 450 since thats the max mppt range. I wouldn't go over 450 to play it safe for cold weather peaks.
Thanks for your help. What do you mean by each one? Do you mean each input via strings? Keep in mind you can have 2 strings in a channel in the inverter on input 1 PV. Same goes for input PV2. I read some one said 500 per channel. if you look at the chart, and the calculations it seems that you can put 24 panels on one inverter. In the chart the voltage for one panel is 39.61. If you multiply that by 24 you get. 950.64 which far exceeds the VOC limit. But if you divide that into 2 strings you get 475.32 which is under the VOC limit. That's why i asked is it 500 VOC per input channel (PV1) and an additional 500 VOC for input channel PV2 only or that refers to PV1+PV2 combined?
 
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Thanks for your help. What do you mean by each one? Do you mean each input via strings? Keep in mind you can have 2 strings in a channel in the inverter on input 1 PV. Same goes for input PV2. I read some one said 500 per channel. if you look at the chart, and the calculations it seems that you can put 24 panels on one inverter. In the chart the voltage for one panel is 39.61. If you multiply that by 24 you get. 950.64 which far exceeds the VOC limit. But if you divide that into 2 strings you get 475.32 which is under the VOC limit. That's why i asked is it 500 VOC per input channel (PV1) and an additional 500 VOC for input channel PV2 only or that refers to PV1+PV2 combined?
 
You can put 500v through each mppt (pv1 and pv2l). So if you have 2 strings of panels the maximum voltage combined of each string is theoretically 500v but keep it to 450v to be on the safe side.
 
Thanks for your help. What do you mean by each one? Do you mean each input via strings? Keep in mind you can have 2 strings in a channel in the inverter on input 1 PV. Same goes for input PV2. I read some one said 500 per channel. if you look at the chart, and the calculations it seems that you can put 24 panels on one inverter. In the chart the voltage for one panel is 39.61. If you multiply that by 24 you get. 950.64 which far exceeds the VOC limit. But if you divide that into 2 strings you get 475.32 which is under the VOC limit. That's why i asked is it 500 VOC per input channel (PV1) and an additional 500 VOC for input channel PV2 only or that refers to PV1+PV2 combined?
Not sure if you figured it out yet so this is simply an informational post.

W=VA This is Watts equals Voltage times Amperage. For example, your panels whether in series or parallel have 1000w to give. If they do it at a higher voltage your amperage through your wires is less so smaller wires (and connectors) will be needed. So if the paralleled panel voltage adds up to 50vDC the 1000w/50vDC=20a However you change your panels to be wired in series to double the voltage up to 100vDC. Now 1000w/100vDC=10a

The SCC takes in the wattage from the panels and converts it to battery charging voltage. Lets say your battery is 12vDC. 1000w/12vDC=83.33a charging current. But always be aware that panels do not push power, loads pull power.

Now in your case you have two SCC in one enclosure. Each SCC (remember you have 2 individual ones in your AIO) can handle it's own array of panels. Arrays are composed of strings of series and paralleled connected panels. The number of strings can be several per array so long as the Arrays total Voc is less than the SCC max Voc. There is also current limits for your wires, SCC and connectors to keep in mind.

The common DC bus from your AIO that has the battery and inverter connected to it works just fine with multiple independent SCC's feeding it since they are in parallel. Being in parallel their currents add to each other but the voltage is the same.
 
You can put 500v through each mppt (pv1 and pv2l). So if you have 2 strings of panels the maximum voltage combined of each string is theoretically 500v but keep it to 450v to be on the safe side.
Just to be clear. Are you saying that i can put up to 500v in pv1 input (2 strings lets say 250v each) and another 500v on pv2 (2 strings of 250v each). That would mean 1 inverter can support 1000VOC. I dont think people are studing the chart i provided in detail. I am trying to see if i can install 24 panels in a series like the chart states, without going over the VOC Limit
 
Just to be clear. Are you saying that i can put up to 500v in pv1 input (2 strings lets say 250v each) and another 500v on pv2 (2 strings of 250v each). That would mean 1 inverter can support 1000VOC. I dont think people are studing the chart i provided in detail. I am trying to see if i can install 24 panels in a series like the chart states, without going over the VOC Limit
A string of series connected panels in parallel with another string of series connected panels the voltage stays the same. So connecting string 1 to string 2 you still have 250v.

No your SCCs can not support 1000Voc. They support the specified max Voc of each one. They than output battery voltage to your batteries and your inverter (part of the AIO).

Please spend some time understanding series and paralleled connections. Also think about the components of your AIO as separate things housed in one box.

SCC (can be either MPPT or PWM)
DC to AC inverter
AC to DC converter charger
Auto transfer switch (ATS)
A computer that controls stuff.
 
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Each mppt can work within the specs of 500v and 18a up to 4kw. The higher voltage and amperage just gives you flexibility for connecting all different brands of panels to the inverter but you can only utilize up to 4kw per mppt.

The voltage is a hard voltage. If you go over there’s a high probability of damaging something. The current rating is a little more flexible. Going slightly over 18a will cause clipping where current is limited.
 
A string of series connected panels in parallel with another string of series connected panels the voltage stays the same. So connecting string 1 to string 2 you still have 250v.

No your SCCs can not support 1000Voc. They support the specified max Voc of each one. They than output battery voltage to your batteries and your inverter (part of the AIO).

Please spend some time understanding series and paralleled connections. Also think about the components of your AIO as separate things housed in one box.

SCC (can be either MPPT or PWM)
DC to AC inverter
AC to DC converter charger
Auto transfer switch (ATS)
A computer that controls stuff.
Thanks for your response. I understand series vs parallel installation, It's just that because the chart never mentioned the word "parallel" and only "series", left me confused; but I see it's implied. I understand now it's a series/parallel combo. The thing about it is the kit does not even come with the extra wiring and connectors needed for a combo installation. So I will have to purchase them or eliminate some panels for a series only installation. Others in this group should be aware of this because I read someone else saying the same thing. Thanks again.
 
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