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  • Diesel
    replied
    Originally posted by kalanic
    Thanks Diesel! Im gonna get another next year. I will see how the factory battery performs with the Optima supporting my high power amp. You think I will need to fabricate a cover for the Isolator?? Will water screw it up if it gets wet?
    No it is sealed. I would make sure that compartment is left open after a day on the water to help prevent terminal corrosion.

    Leave a comment:


  • Leroy
    Guest replied
    Diesel;

    I think what Matt is concerned about and I think could be a concern, you run the deep discharge battery dead, then when you start not only is the current from your good battery starting the boat, but is surging into the dead battery. If you could delay the relay connection until the motor started there would only be one load at a time on the good battery.

    Could I add a second relay in the same manner as the first, but energizes to cut the deepcycle out when the starter motor circuit is energized? Not quite following you here but either way it is not necessary.

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  • kalanic
    replied
    Thanks Diesel! Im gonna get another next year. I will see how the factory battery performs with the Optima supporting my high power amp. You think I will need to fabricate a cover for the Isolator?? Will water screw it up if it gets wet?

    Leave a comment:


  • Diesel
    replied
    Great looking install!!

    I love those billet Optima trays and wish I had room to use a pair.

    Leave a comment:


  • kalanic
    replied
    Finally finished my battery install between our crappy weather....hope it works!
    Attached Files

    Leave a comment:


  • Diesel
    replied
    Originally posted by Matt L.
    Dooh! I mean, Sweet!!! Sounds pretty simple then.

    So when the relay is energized by the ignition switch I get both the starting batt and the deep cycle in parallel with both the starting and charging systems? Yes

    When the ignition system is off the relay opens between the starting and deep cycle batteries, leaving just the deepcycle batt exposed to discharge. Exactly

    If that is all right then my only concern is for the deepcycle. Will it be exposed to the sudden and deep draw of the starter motor?!? If so, won't this damage the deep cycle? Not enough to matter. Your deep cycles will be fine.

    I spent big bucks on these big AGM batteries and I don't want to ruin them. The boss....er wife will kill me if I have to explain why that $150+ deepcycle was ruined by adding the relay.

    Could I add a second relay in the same manner as the first, but energizes to cut the deepcycle out when the starter motor circuit is energized? Not quite following you here but either way it is not necessary.

    Thanks,

    Matt
    Response in blue above......

    Leave a comment:


  • Matt L.
    replied
    Originally posted by Diesel
    Buy the relay and wire it according to the first post and forget about it.
    Dooh! I mean, Sweet!!! Sounds pretty simple then.

    So when the relay is energized by the ignition switch I get both the starting batt and the deep cycle in parallel with both the starting and charging systems?

    When the ignition system is off the relay opens between the starting and deep cycle batteries, leaving just the deepcycle batt exposed to discharge.

    If that is all right then my only concern is for the deepcycle. Will it be exposed to the sudden and deep draw of the starter motor?!? If so, won't this damage the deep cycle?

    I spent big bucks on these big AGM batteries and I don't want to ruin them. The boss....er wife will kill me if I have to explain why that $150+ deepcycle was ruined by adding the relay.

    Could I add a second relay in the same manner as the first, but energizes to cut the deepcycle out when the starter motor circuit is energized?

    Thanks,

    Matt

    Leave a comment:


  • djhuff
    replied
    Let me know what you find Diesel. I've got til Saturday to get this figured out before I christen the boat.

    Leave a comment:


  • Diesel
    replied
    Originally posted by Matt L.
    Okay, now my head is spinning from reading this stuff!!!

    I just want a system that will automatically disable the starting batt when the ignition is off, enable the deep cycle when the ignition is off, and charge both properly when running.

    Is that too much to ask???!!!
    Buy the relay and wire it according to the first post and forget about it.

    Leave a comment:


  • Matt L.
    replied
    Huh???

    Okay, now my head is spinning from reading this stuff!!!

    here is what I've got to work with.

    Perko Switch, Optima Blue top starting batt, Deka AGM deep cycle.

    I just want a system that will automatically disable the starting batt when the ignition is off, enable the deep cycle when the ignition is off, and charge both properly when running.

    Is that too much to ask???!!!

    Perko is under a seat (where kids/babies always end up falling asleep) and is a real PITA to remember to switch around.

    I've got a boat and crew to manage (wife and 3 boys), I don't need to worry about the batteries too!!!

    Thanks,

    Matt

    Leave a comment:


  • Diesel
    replied
    Originally posted by djhuff
    Diesel, I'm running the relay. Do you see any problem with energizing the relay with the "accessory" lead rather than the "run" lead from the ignition. Reason being, If the stereo battery is low and I try to start... the batteries will be in parrallel. Wouldn't this cause the starting battery to discharge into the stereo battery at the same time it is trying to start? I was thinking that if I use the accessory lead, when I turn the key to "start", the relay will be open, and the starting battery will be isolated while starting, but switched back to parallel once the engine is running. I have nothing hooked up to the accessory switch right now (radio is solely hooked up to second battery with manual off/on switch). Thanks
    I don't think the accessory lead on a boat works like an auto where it is not energized during start up?? When in the run or start position I think the accessory is still energized. I think the accessory and "run" are all the same when the key is to the right.

    Actually now that I think about it you might be on to something here. I will have to get my fluke out to see what is going on in the ignition switch.

    If I am wrong this is a very good way to alleviate the concern regarding large flows of current at start up.

    Leave a comment:


  • djhuff
    replied
    Diesel, I'm running the relay. Do you see any problem with energizing the relay with the "accessory" lead rather than the "run" lead from the ignition. Reason being, If the stereo battery is low and I try to start... the batteries will be in parrallel. Wouldn't this cause the starting battery to discharge into the stereo battery at the same time it is trying to start? I was thinking that if I use the accessory lead, when I turn the key to "start", the relay will be open, and the starting battery will be isolated while starting, but switched back to parrallel once the engine is running. I have nothing hooked up to the accessory switch right now (radio is solely hooked up to second battery with manual off/on switch). Thanks

    Leave a comment:


  • Diesel
    replied
    Originally posted by prostar205
    Diesel -

    I had a little change in plans. I am currently only going to use the Perko switch and no isolator - for now. Am I still going to be OK with "mixed" batteries between battery 1 (lead acid type) and battery 2 (Optimas)?
    You will still be fine if you choose to use the perko. Just don't forget to leave it on both or turn it to off when the battery is running, or etc, etc, etc............

    Originally posted by prostar205
    The way I see it is: when using the Borg Warner Relay, as soon as you energize the ignition (motor off), all the batteries as immediately put in parallel. At least with the Perko Switch, I can turn it to battery 1, start the engine and then turn the Perko switch to both to allow both batteries to charge.
    You can wire the relay to function how ever you want. If you add a DPDT switch instead of using the ignition switch you will basically have a perko that is controlled from a rocker switch in the dash. A MC bilge switch cover works great since is already says auto, off, and manual. By adding the DPDT switch you can have the relay work off the ignition switch (automatic), completely off (full isolation), or manually closed (full time parallel). This is how my jeep is wired.

    Leave a comment:


  • OhioProstar
    replied
    IMHO it is hard to trust a relay or isolator without upgrading your alternator and associated fuses/wiring. All of a sudden you are spending quite a bit and putting a lot of faith in a single point of failure (isolator/relay). For a lot less you can run a switch($25), I used BlueSea, and a multi-bank changing system($100) that you just plug in at night to keep both batteries changed. If a battery is drawn too far down then you just turn the switch to the back up battery and once running turn back through the ON position to the main bank for charging. I understand that it is not automatic, but it seems the most cost effective and the least problematic in the long run.

    Leave a comment:


  • prostar205
    replied
    Diesel -

    I had a little change in plans. I am currently only going to use the Perko switch and no isolator - for now. Am I still going to be OK with "mixed" batteries between battery 1 (lead acid type) and battery 2 (Optimas)?

    The way I see it is: when using the Borg Warner Relay, as soon as you energize the ignition (motor off), all the batteries as immediately put in parrallel. At least with the Perko Switch, I can turn it to battery 1, start the engine and then turn the Perko switch to both to allow both batteries to charge.

    I am now at the point of installing the amps and headunit (Pioneer Premier DEH-P860MP) and I have a few questions. I will PM you this morning.

    Leave a comment:

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