Search results

Using my case as an example, using freezing as a record low, I should keep my solar panel array at or below 409 volts?

I am a bit lost with the difference between the DC input range and the full-power MPPT voltage range. If I understand, the 18Kpv can support intake voltage from an array up to 600 volts.

The worst-case scenario brings me within 19 volts of max. What is the consensus? Total string OC voltage: 450.09 Nominal maximum power: : 4050 Worst case temperature: -1.1 Temperature coefficient (Voc): -0.27 Temperature coefficient (Pmax): -0.34 For these, your: Total worst case...

Does that mean each mppt input requires the minimum 140-volt start-up voltage? In this case it would around 160 volts for he 4 panels

Correct, I meant to say one string on mppt 1 and the other two on mppt 3 and 4 with the fourth one only having 4 panels

I have 24 panels at the moment, the space where they are installed can handle 30. Is it possible to run 10 panels on mppt 1 and mppt 2 and the remaining 4 on mppt 3 until the other 6 panels are sourced? The manual suggests all 3 strings need to have the same amount of panels. Please advise. 10...

Does the ground have to be of the same size?

The EG4 18kv will live In the carport, 170 feet away from the critical loads panel it will feed. The subpanel will have a 70-amp (80-amp if possible) main breaker. Do I need #2AWG or would #4 AWG for the approx 170tf run? A bit confused on whether the max voltage drop of 3% is for continuous only.

Live and learn! Thank you

The 18k manual calls for DC disconnect and suggests the IMO. I am also running the Tigo 2f's with the 18K built-in RSD

I was considering that option, Thanks for the input.

In short, I need to install these outside the structure

NEC dictates DC circuits are to be in metal conduits within a structure. The IMO DC disconnect is Plastic/pvc, do I need to install these inside a metal enclosure? I planned to mount 3 DC disconnects on top of a metal enclosure using chase nipples. Run my PV wire to the metal enclosure via a...

Front ISC: 13.96 Rear: ISC 9.84 Do you add the front and rear values or is the amperage of the panel determined by the lowest current value? Thank you

At that point, we were discussing liquidtight Flxible MC. The run from the roof to where it goes into the structure is 10ft. Four feet on the roof and about another 4 feet down the wall.

Okay, I think I will process all this information as I sleep. One last thing, in your initial comment you mention a condition, "when wet." I am not sure how that fits, can you elaborate? Here, wet weather happens in cool months, and roof temps are not hot. It's fair to say that I have not taken...

Okay, now I am in over my head. No, I did not consider this, and I am not sure how to factor that in. Here is my best shot Isc=Is×Derating Factor Assuming Is is 14 amps: Isc=14 A×1.56Isc=14A×1.56 Isc=21.84  Assuming this is correct, and now I am .84 out of spec, what are my options? Run...

Another consideration! Let's say the standard ampacity for a 10 AWG THN wire with 60-degree Celsius insulation is 30 amperes. Applying the derating factor: Rated Current Capacity=Ampacity×Derating Factor Rated Current Capacity=30A×0.70=21A Each string is producing about 14 amps, so I should...

Even if I taped the wire nuts? kidding! Those Midnite boxes are pretty nice, but in my case, the breakers on the roof are not readily accessible. I running IMO DC breakers inside the structure.

Okay. It's becoming clear. It's better to keep asking and avoid a costly mistake. Thank you

Thank you for your input. I was planning on running the PV wire into a NEMA 4 junction box to make the transition to THHN. The IMO disconnects are located as soon as the wires come into the structure. The run from the roof to the point where they enter the structure is about 15ft. Everything...

I was under the impression I could not run it if the voltage was higher than 32 volts, had to be MC.

Din rail terminal block

Could Liquidtight Flexible Metal Conduit be used throughout the installation? There seems to be some discrepancy as to whether MC Cable can be run exposed to the weather.

Awesome. Can you share a link to that video? Thank you

Would this MC Cable meet NEC guidelines to run on the roof and into the structure? Parking Deck/Lot Cable - Interlocked Galvanized Steel Armor w/ Overall PVC Jacket - Type MC Standards, References, & Ratings ▲UL 66, 83, 1569, 1581, 2556, File Number: E80042 ▲PROP65 - Warning use caution and...

There are 3 strings in series any junction box on the roof would transition from PV wire to THHN, into the structure and through individual DC disconnects. Two of the arrays will be paralleled at input 1 of the inverter, EG4 18K.

These are roof mounted panels, the midnite combiner looks more suitable for ground mounted panels. Am I mistaken?

No permit, however I am doing everything to meet code. Is MC cable rated for outdoor runs? for example, junction box on roof to the interior of the structure.

Actual PV wire and THHN running high DC voltage, correct? Thank you

I have seen installations where the PV wire is run into a junction box somewhere next to the solar panel rails, transitioned to THHN, and from that point on in conduit into the structure. Instead, could I run my PV wire into a junction box to collect them all and send them out via conduit into...

At the moment the plan is if after collecting data, input 1 cannot be paralleled, I will be adding panels as you suggested to open the 3rd input for further expansion.

Yes, I agree. I do have room for extra panels.

Very interesting information. Thank you. As I process all this information I am leaning towards using all 3 MPPT inputs and monitoring the system for 6 - 12 months. With that data, I should know if connecting 2 strings to input 1 is a viable option. I agree with you, just going parallel puts me...

On the voltage side, we are humming along at about 332V, calculating the temp coefficient 358V. Specs are 230 - 500-volt. The nominal MPPT tracker voltage is 360V