Power 2 Max Type S Battery Replacement Question.

Spartacus1981
Spartacus1981 Posts: 254
edited February 2018 in Workshop
Good Afternoon,

Can anyone tell me if either a CR2450, or a CR2450B battery will work in a P2M Type S Power Meter ? My P2M displayed a red light on the crank arm yesterday (rather than short blinking green LED I'm used to), and the Watts just stayed at 139 from mid ride and were not changing on my Wahoo. I assume the red LED means battery is dead ?

P2M online info mentions you should replace with a Renata CR2450N type battery .. But I cannot find the CR2450N here in any shop in Palma de Mallorca, but have the CR2450 and a CR2450B battery. Can anyone tell me if any of the batteries I have will work ?

Many thanks

Comments

  • StillGoing
    StillGoing Posts: 5,211
    I'd be wary of using anything other than what P2M specify. Its an expensive unit to bugger up the operation by using an incorrect battery specification and I recently had to change the battery in mine. Luckily a back street shop had a shelf full of them. Contact P2M and ask them. They usually get back in a pretty quick time.
    I ride a bike. Doesn't make me green or a tree hugger. I drive a car too.
  • Thanks Philthy3. I think you're right. I'm just going to order the correct battery and wait for it to arrive.
  • sungod
    sungod Posts: 16,432
    any cr2450 from a reputable manufacturer should be ok, duracell, varta, sony, panasonic, energizer, etc. for instance

    the 'n' is simply a letter renata stick on the end of the generic code to say 'this is a renata cr2450', whereas sony use 'b' on the end, and duracell use 'dl' instead of 'cr'

    p2m may refer to the renata one simply because that avoids people using cheapo cells of unknown provenance
    my bike - faster than god's and twice as shiny
  • StillGoing
    StillGoing Posts: 5,211
    sungod wrote:
    any cr2450 from a reputable manufacturer should be ok, duracell, varta, sony, panasonic, energizer, etc. for instance

    the 'n' is simply a letter renata stick on the end of the generic code to say 'this is a renata cr2450', whereas sony use 'b' on the end, and duracell use 'dl' instead of 'cr'

    p2m may refer to the renata one simply because that avoids people using cheapo cells of unknown provenance

    Interestingly when I was sourcing my replacement, I was handed a CR2450 from a shop and told it was exactly the same. Luckily I checked the profile to see it might have been the same size and voltage, but it would have sat proud of the P2M casing.
    I ride a bike. Doesn't make me green or a tree hugger. I drive a car too.
  • sungod
    sungod Posts: 16,432
    philthy3 wrote:
    Interestingly when I was sourcing my replacement, I was handed a CR2450 from a shop and told it was exactly the same. Luckily I checked the profile to see it might have been the same size and voltage, but it would have sat proud of the P2M casing.

    a cr2450 cell is 24.5mm diameter and 5mm high, but what is noticeable is the renata cell has a larger diameter cathode, also with the cathode being a larger proportion of total cell height vs. anode than some other manufacturers

    if p2m have made the battery recess only fit the renata shape then that imo would be an odd design choice, if renata ever stop production (it happens) p2m customers would be stuffed

    electronically they do the same, the op should just try a generic cr2450 if it's a hassle trying to get the renata cell

    for instance...
    https://www.alliedelec.com/m/d/e1a5e5a5 ... 564224.pdf (renata)
    https://www.jameco.com/Jameco/Products/ ... 119216.pdf
    http://ultran.ru/sites/default/files/ca ... 2450_0.pdf
    http://downloads.cdn.re-in.de/1200000-1 ... ER_SET.pdf

    ...show the renata cell has larger cathode
    my bike - faster than god's and twice as shiny
  • Thank you to both of you for your input. I really have no clue about batteries like sungod, but he was correct. I emailed P2M and they replied that any regular CR2450 battery should work (which it did actually). I found some here in a shop from a brand called Extrastar (was just Extrastar CR2450) and installed it and we're back in business it appears. I did however end up ordering a Renata CR2450N in the meantime when ordering a new coloured ring for my unit so may change it to that one once it arrives to be safe. Thank you both for your help.