Charge controller efficiency

dsimonl
dsimonl Registered Users Posts: 6
I need a charge controller for an off-grid cabin. My array will be fairly small compared the the battery bank, so every watt counts!!

I have the selection narrowed down to the FN60 and the XW60.

Outback claims <1w standby consumption vs. 2.5w with the Xantrex. I assume this can be offset with the dynamic MPPT of the Xantrex, so shouldn't be an issue.

Outback publishes their efficiency curve, but I've not seen any data on the Xantrex. This difference could make a big impact.

Does anyone have any data? Real-life comparisons?

Thanks!

Comments

  • Solar Guppy
    Solar Guppy Solar Expert Posts: 1,989 ✭✭✭
    Re: Charge controller efficiency

    From testing this spring on the FM and XW units:

    Volt Night Active Idle ( PV just removed but still online )

    XW

    48V 3.3w 4.1w

    24V 3.0w 3.9w

    12V 2.7w 3.8w

    FM

    48V 2.2w 9w

    24V 1.7w 9w

    12V 1.3w 9w

    The Outback has substantially higher active losses than the XW so for under say a couple hundred watts the XW is higher efficiencys in all configurations. The FM at higher power levels and lower battery voltages has the edge ... at 48V, they are very similar
  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭
    Re: Charge controller efficiency

    And, If your need is not immediate, the Midnite Classic MPPT Charge Controller is anticipated to begin shipping later this year. It just might have some edge, as it will be a few years newer in design. Its Firmware will be updatable in the field, and have many cool benefits.

    The Classic is currently in Beta Test, but is possibly six months away ... I've been waiting to look at this new CC. It is being done by vetrans in the Solar field -- the founders of Outback IIRC, vertans of Trace/Xantrex, and so on.

    Just MHO, I have NO vested interest in this stuff, but might be worth a look.

    Good Luck, Vic
    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • halfcrazy
    halfcrazy Solar Expert Posts: 720 ✭✭✭
    Re: Charge controller efficiency

    Yes beta testing of the Classic is Very promising I can assure you it is worth the wait. I have been testing a Xantrex XW60, Outback FM60 and a classic for 6 months now and it looks good.

    If i had to buy a controller today I would likely go with the XW even though the no fan thing worries me. They have Outback beet on the tracking.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Charge controller efficiency
    halfcrazy wrote: »
    ... a classic for 6 months now and it looks good.

    it=Classic?

    -Bill :confused:
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Solar Guppy
    Solar Guppy Solar Expert Posts: 1,989 ✭✭✭
    Re: Charge controller efficiency

    I have extensive testing on all the major controller and with very tight tolerance arrays and lab quality power analyzers. The New MorningStar unit will have them all beat for features, performance and efficiency when it makes it to market ... I don't have access to a Midnite unit, so we will have to see when both controllers come to market which is better :roll: , Like boB's work, MorningStar has been in beta for a while and won't be released until its 100% but is targeted for this year availability
  • boB
    boB Solar Expert Posts: 1,030 ✭✭✭✭
    Re: Charge controller efficiency
    The New MorningStar unit will have them all beat for features, performance and efficiency when it makes it to market ...


    SG, I don't suppose you can say anything about why the efficiency will be good ? :D

    boB
  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,730 ✭✭✭✭✭✭
    Re: Charge controller efficiency
    halfcrazy wrote: »

    If i had to buy a controller today I would likely go with the XW even though the no fan thing worries me. They have Outback beet on the tracking.

    Why worry about the fan ? For 50 bucks you can run the warranty out from 5 to 10 years.
    "we go where power lines don't" Sierra Nevada mountain area
       htps://offgridsolar1.com/
    E-mail offgridsolar@sti.net

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Charge controller efficiency

    I like equipment that does not have fans... Sealed enclosures with external heat-sinks are the way to go for long life/low service requirements.

    When I designed telecommunications equipment--fans were a major issue... Have to have fan fail detection, dust filters, servicing requirements, etc.

    If somebody can design a "power supply" that has high efficiency (less power to dissipate) and no air through the middle of the system (and proven performance at spec. conditions)--I would be hard pressed to choose another unit with fans.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • boB
    boB Solar Expert Posts: 1,030 ✭✭✭✭
    Re: Charge controller efficiency
    I don't have access to a Midnite unit, so
    ......

    You wouldn't like the Classic... It's not fan-less.

    boB
  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,730 ✭✭✭✭✭✭
    Re: Charge controller efficiency

    I might like it if I knew how it was designed. When I worked for the old HP our test equipment could have a fan only if the equipment could operate in 100F air with a disabled fan. In other words the fan was there for doomsday operation that most likely the equipment would never see. It was designed in to last and it is the reason that old HP gear sells for so much.

    I would say if you use a fan it should be a nice quiet constant DIN so people could work near it (sleep near it) and not be disturbed by constant cycling. Like test gear on a bench in engineering.
    "we go where power lines don't" Sierra Nevada mountain area
       htps://offgridsolar1.com/
    E-mail offgridsolar@sti.net

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Charge controller efficiency
    I would say if you use a fan it should be a nice quiet constant DIN so people could work near it (sleep near it) and not be disturbed by constant cycling. Like test gear on a bench in engineering.

    Ah... You had those long nights at the lab bench too. ;)

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset