What breakers are compatible with the XW PDP?

new2PV

HI looking to add some breakers for the XW PDP what DC breakers are compatible? Will the midnite solar ones work? . I have been getting some pretty crazy prices for the DC breakers in 60AMP...

Vic

Believe that Schneider still uses the E-Frame breakers, that are 1" wide for many/all of the DC breaker positions in the PDP. These will be the "CD" style, although believe that the CDs are no longer made. The CF is a much better breaker, IMO, if you need 1" wide breakers.

MidNite uses F-frame breakers, IIRC but primarily for 125 and up Ratings, usually for Inverter connections.

But, before you buy any of these breakers, please make sure that you have the system designed, and you know what you will need to do the job that needs to be done, IMO.

FWIW, Vic

Vic

The Host of this site carries some of the SQ-D E-Frame breakers ... they are kinna hidden:

http://www.solar-electric.com/inverters-controllers-accessories/inverters/xain/nexaxwseinan.html

Again, FWIW, VIc

new2PV

Thanks, Vic. The 60 amp will be for the charge controller input and output, however I am sizing the array for a max short circuit current output 48 amps , conductors will be sized at 65 amps.

new2PV

I have been working with this host of this site to work out a deal for some breakers, also the sales staff is very friendly and respond quickly to all my questions.:-)

BB.

new2PV,

Just to be clear, if you are working with MPPT type charge controllers... They are (more or less) constant power devices. Meaning it is the power in = power out, and not current in = current out.

For example:

• 100 Vmp * 40 amps Imp = 4,000 Watts input
• 4,000 Watts input / 52 Volts battery charging = 77 amps charging battery.

Also, remember that in the US/North America, we only run breakers (and wiring) at 80% of the breaker's rating:

• 60 amp breaker * 0.80 = 48 amps continuous (if you run >~80% of breaker rating, it may trip at some point)

If you want 60 amp actual current:

• 60 amps / 0.80 NEC derating = 60 amps * 1.25 NEC derating = 75 amp minimum ~ 80 amp rated breaker (and wiring)

-Bill

new2PV

The Schneider MMPPt-60-150 will only output 3500 watts with an allowable input of 6700 watts. I am not sure if this breaker is a 100% rated breakers, all the midnite solar DC breakers are 100% current rated. The instructions say to plan your ARRAY current to max 48 amps to allow increased output at colder temps, do you think the 60a breaker will trip at 48 amps??

BB.

Solar arrays/PV electronics are a mess with NEC/UL/etc...

Technically, Imp falls (slightly) as temperature drops. Mostly, Imp/Isc is proportional to the amount of sun hitting the panels (direct, reflections from sand/water/snow). So--On the array side, panel temperature itself is not really an issue (the temp coeff for Imp is something like 1/5 of Vmp--or even a bit less, and in the opposite direction).

However, with MPPT controllers, you can easily have a 20% or greater change in Vmp which will affect the output current Ibatt by 20% (add variation in battery voltage, I=P/Vbatt) and the output side of the MPPT controller can vary quite a bit.

However, most MPPT controllers will current limit to their rated (or programmed) current limit.

While it appears that NEC requires the 60 amp output to be derated to 48 amps (80% of rated value)--I don't think that is correct. Instead, if you plan on 60 amp output, then the output breaker needs to be sized to 60 amps * 1.25 NEC derating or >=75 amps minimum.

-Bill

inetdog

new2PV wrote: »

The Schneider MMPPt-60-150 will only output 3500 watts with an allowable input of 6700 watts. I am not sure if this breaker is a 100% rated breakers, all the midnite solar DC breakers are 100% current rated. The instructions say to plan your ARRAY current to max 48 amps to allow increased output at colder temps, do you think the 60a breaker will trip at 48 amps??

Which is really odd, since Vmp increases with lower temperature, but Imp and Isc actually go down for all of the panels I have checked the specs on.
You do not want the low temperature string Voc to be above the DC volts interrupting capacity of the breaker, and changing the current spec will not affect that directly.

new2PV

The breakers recommended by Schneider are 60A for PV input and 80 for DC battery. The input breaker is a 100% rated DC breaker here are the numbers, not sure on the output breaker being a 100% current rated breaker.

PV/MPPT60 DC-Breaker (ARRAY DISCONNECT) Airpax 60A 160VDC MAGNETIC LONG-DLY PNL- MT UL/CSA MFG p/n: 279-1-33909-60

DC Battery Breaker (BATTERY DISCONNECT) Carling Series, 80A/125Vdc/12pc Mfg P/N: EA1-B0-16-680-32A-BF

new2PV

inetdog wrote: »

Which is really odd, since Vmp increases with lower temperature, but Imp and Isc actually go down for all of the panels I have checked the specs on.
You do not want the low temperature string Voc to be above the DC volts interrupting capacity of the breaker, and changing the current spec will not affect that directly.

Your are probably correct I could have read that wrong, but they did mention because of factors like snow they are suggesting 48 amps@25C array sizing as max input.