Breaker from charge controller to batteries trips at 1460 wa

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vetenergy
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Breaker from charge controller to batteries trips at 1460 wa

Post by vetenergy » Mon Dec 25, 2006 8:31 am

I just installed a system that consists of 16 165W, 24V solar panels, 16 6V batteries that are properly connected into a 24V system.

The solar panels are wired 2 in series making 8 parallel connections to the combiner box. Voltage readings up to the combiner box are 84V for each circuit, which is correct.

We are using 2 FX3624 inverters.

Problem: When the panels reach around 1460W input to the MX-60 charge controller, the breaker from charge controller to battery trips.

What do I need to do or adjust to resolve this problem?

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Post by mvrck » Mon Dec 25, 2006 8:57 am

What size breaker did you use for the output of the MX60?

With the 60amp breaker, it should not trip at 60 amps. Check to be sure your connections are tight. If there is excess heat, it would cause the breaker to trip early. What current reading is on the MX60 just before it trips?

The MX60 can be programmed to put out 70 amps, in which case you might want to put a 70amp breaker on it output. You may have to change the wire size one bigger as well.

Thanks
Maverick
 
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crewzer
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Post by crewzer » Mon Dec 25, 2006 10:02 am

Vetenergy,

With respect to the problem youÔÇÖve identified, I agree with MaverickÔÇÖs suggestion to check the breaker from your MX60ÔÇÖs output. However, based on the information youÔÇÖve supplied, your system has another problem that you may wish to address.
I just installed a system that consists of 16 165W, 24V solar panels, 16 6V batteries that are properly connected into a 24V system We are using 2 FX3624 inverters When the panels reach around 1460W input to the MX-60 charge controller
It appears that your system has a 16 x 165 W STC = 2,640 W STC array charging a 24 V battery bank. This is WAY too large an array for a single MX60 to handle. In fact, OutBack suggest an array rated at 1,600 W as the practical limit for a 24 V system.

At full power on a cold day, charging current from a 2,640 W array could be ~90 A at 28 V. Even at an 85% combined operational efficiency for the PV array, the wiring and the controller, charging current at 28 V could be ~80 A. So, even with output breaker problem solved and your MX set for 70 A output, it will limit charge current to your batteries. With 80 A or 90 A throttled back to 70 A, somewhere between 10 A or 20 A X 28 V = between 280 W and 560 W -- effectively the net output capability of between two and four of the PV modules ÔÇô will be wasted.

ItÔÇÖs possible that you misstated your system configuration, and/or that I misunderstood (hey, itÔÇÖs Xmas!). However, if not, then you may want to consider adding a second MX60 to your system in order to realize full performance from your system.

HTH, and Best Wishes for 2007!
Jim / crewzer
090805 System Configuration: 966 W STC (849 W CEC PTC) 48V PV array, FM80, 24V x 400 Ah AGM battery bank, FX2524T w/ BTS, Hub-4 & Mate; Link-10 w/ BTS, & E-Panel.

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mvrck
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My RE system: 3.1 kW (BP 60W) on 2x MX60s
560W (Kaneka 60W) on 1 Classic 150
1080W (Day4) on 1 Tristar MPPT 60
GVFX3524 + PS2AC/DC, MATE, HUB4, Charles 24V 30A Charger, Generac S4001, Trimetric 2020, WattPlot, greenMonitor Lite, 400AH Bank (4 ea Rolls Surrette S530 Batteries), and a lot of other solar refuse...
Location: Austin, Texas
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Post by mvrck » Mon Dec 25, 2006 10:36 am

The egg nog has my math skills offline. But if you are craming 2640W into the MX60, you should at least get some throttling before it trips the breaker? :???: . Double check the current limit setting and make sure it is at or under the output breaker size.

For my system of 1700W, I never see more than 1100W :shock: so I use 65% for my future array size limit. Even at my 65%, your array is still too large for one MX60.

Hopefully your birthday is just around the corner... Sounds like a new mx60 is in order. You could also get a C40 just to handle the left over panels.

Thanks
Maverick
 
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My Outback: 3kW PV STC + MX60s + GVFX3524 + PS2 Combo = Helping Myself to the Sun!

vetenergy
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Is there an EZ way to program MX-60 amps

Post by vetenergy » Tue Dec 26, 2006 6:14 am

Need steps to program MX-60 amps to increase to 70 amps output to batteries.

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Post by sparky » Tue Dec 26, 2006 6:48 am

Do you have the 70 amp breaker?

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Re: Is there an EZ way to program MX-60 amps

Post by DavidB » Tue Dec 26, 2006 10:58 am

vetenergy wrote:Need steps to program MX-60 amps to increase to 70 amps output to batteries.
If you have the 70A breaker already then from the main menu just go to the "charger" menu. The Amps Limit is listed right there.

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crewzer
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Post by crewzer » Tue Dec 26, 2006 1:02 pm

For my system of 1700W, I never see more than 1100W Shocked so I use 65% for my future array size limit...
Yikes! :shock: My polycrystalline array's output (mid-day, near end of bulk/MPPT stage) is typically ~80% - 83% (580 W - 602 W) of its STC rating... I might have to stop complaining! :wink:

Last year's measurements: http://www.outbackpower.com/forum/viewtopic.php?t=952

Happy Holidays, all!
Jim / crewzer
090805 System Configuration: 966 W STC (849 W CEC PTC) 48V PV array, FM80, 24V x 400 Ah AGM battery bank, FX2524T w/ BTS, Hub-4 & Mate; Link-10 w/ BTS, & E-Panel.

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Post by DavidB » Tue Dec 26, 2006 5:06 pm

So I won't even mention how my system consistently peaks well over the STC rating.. :mrgreen: It's a lot colder than Texas here though and there is a small amount of snow cover. Array is on a top-of-pole mount at 65 degrees currently.

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crewzer
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Post by crewzer » Wed Dec 27, 2006 10:05 am

...my system consistently peaks well over the STC rating...
:cool: :cool:
090805 System Configuration: 966 W STC (849 W CEC PTC) 48V PV array, FM80, 24V x 400 Ah AGM battery bank, FX2524T w/ BTS, Hub-4 & Mate; Link-10 w/ BTS, & E-Panel.

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crewzer
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Post by crewzer » Thu Jan 04, 2007 3:57 pm

Vetenergy,

Problem solved?

Regards,
Jim / crewzer
090805 System Configuration: 966 W STC (849 W CEC PTC) 48V PV array, FM80, 24V x 400 Ah AGM battery bank, FX2524T w/ BTS, Hub-4 & Mate; Link-10 w/ BTS, & E-Panel.

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