Viking smart charger from Harbor Freight

Discussion in 'Equipment' started by hammick, Jun 27, 2019.

  1. hammick

    hammick Long timer

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    OK. I have a handful of other quality chargers but they are not with me at the moment so I have the following issue (or non-issue).

    The Viking microprocessor smart charger seems to work well on big and small batteries. It works on regular flooded, AGM and gel.

    On my ATV with a five year old AGM battery it maintains the battery in float at 13.1 - 13.2 volts. Didn't really give the low float voltage a thought since I'm at my remote retreat with solar and don't float anything long term up here.

    I put it on my R1250GSA with a three month old AGM battery and it maintains that battery in float at 13.5 - 13.6 volts.

    MY ATV cranks over just fine but I can't understand why it would float at .4 volts lower. Initially I was thinking I should get a new battery but I saw a review on Youtube of the charger and it was floating his snowmobile AGM battery at 13.1 volts.

    Do the BMW factory batteries have a higher resting state of charge? I though they were Yuasa AGM batteries just like my ATV.

    I really don't want to spend $60 on a new battery if mine is fine but on the other hand I need a reliable starting ATV or I could get stranded after dark in Griz country.
    #1
  2. JimVonBaden

    JimVonBaden "Cool" Aid! Supporter

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    Are they identical spec batteries?
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  3. hammick

    hammick Long timer

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    Not sure Jim. The ATV Yuasa is 18.9ah and 270cca. Not sure what the BMW battery specs are.

    I would have thought the charger would do a certain float for AGM mode. It's either really smart or a POS. Seemed like a great $19 charger. I will leave it on the ATV overnight and see if the float voltage comes up.

    I have a bad battery from my wife's side x side that is the same size Yuasa. The charger also floats it at 13.1 - 13.2 volts. She is bringing a new battery with her when she arrives on Saturday. If it floats at 13.1 - 13.2 volts mystery solved.

    Most smart chargers don't display the voltage but I've put meters on enough AGM batteries in float to know they should be floating at 13.5 to 13.6 volts.
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  4. JimVonBaden

    JimVonBaden "Cool" Aid! Supporter

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    Resting voltages are variable depending on the battery. The 2015 BMW R1200GS battery is a 230 CCA, 14 AH battery. It will rest, depending on the model, between 13.8 and 14.2. The R1250 uses the same battery.
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  5. hammick

    hammick Long timer

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    Well after further testing I believe this charger is a cheap POS. Left it on the ATV overnight and it never went to float. Was at absorption level voltage 14.5 - 14.7 volts this morning. Unplugged it and plugged it back in and it went to float within five minute is now floating at 13.4 - 13.5 volts same as my GSA. So now I'm wondering if this might have caused the early demise of my wife's side x side battery and whether it did any damage to my ATV battery last night.

    Being cheap often leads to much more expense down the road. I'm going to exchange it for a new one at HF and only use it for supervised charging.

    BTW Jim the resting voltage of my R1250GSA battery after 24 hours is 13.1 volts. Resting voltages right after a full charge are higher. It takes a number of hours to settle down.
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  6. KingOfFleece

    KingOfFleece SplitWeight(tm) waterproof seat covers Supporter

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    Odyssey batty has some good tech advise for AGM batteries on their site. For their product, over 5 amps needs to be delivered to the AGM for proper maintenance. They have a specific list of tender type products that are approved-many big(er) names are not on the list.
    #6
  7. mouthfulloflake

    mouthfulloflake Not afraid

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    very specific voltage range to adhere to as well for best life from an odyssey battery, its hard to duplicate with any SUB$100 chargers in my experience.
    #7