/ Register

Isolators, voltage drop...

Discussion in 'General Car Audio Discussions' started by Slump_Da_Hustla, Jan 29, 2003.

  1. Slump_Da_Hustla

    Slump_Da_Hustla Full Member

    Is it true that isolators can cause up to 2 volts of voltage drop, depending on the manufacturer and if so how do you know how much voltage a given unit will draw? Somebody said I should get a selanoid instead of an isolator because there's no voltage drop and they're cheaper and easier to install. Somebody else said I don't need either cuz I'm using 2 optima battaries and I shouldn't believe everything I read on the internet. If I do get an isolator is there a certain brand I should get, and if so where do I get one? NAPA only has up to 120 amps... I'm getting my shit installed on Sat. So I'm trying to get one like tomorrow or the next day...
     
    Slump_Da_Hustla, Jan 29, 2003
    #1
  2. sandt38

    sandt38 Full Member

    Napa can order 240 amp isolators as well. There is not a 2 volt drop, my rear battery sees 15 volts, and yes I have checked it myself. You are correct, don't believe everything you read on the internet ;) . I do highly suggest an isolator (what if 1 battery gets weak while the other stays strong? It will pull voltage from the good one leaving you SOL) and also highly reccomend against the relay type "isolators". Stinger also makes isolators and I believe audiobahn may as well.
     
    sandt38, Jan 30, 2003
    #2
  3. peter_euro

    peter_euro Full Member

    Any connection will cause a voltage drop... 2 volts sounds excessive though... probably 0.5 volt at the most... However, the more connections and ground points you have, the more voltage drop at the point of interest you will see (it all adds up...) Solenoid type is the worse of 2 evils but it is cheaper (then again, you get what you pay for...) But by design, either type of isolator will cause voltage drop (nothing is for free, LOL) and the diodes will eventually burn out... If you routinely listen to stereo with engine off and for extended time, then you could install an isolator but you really do not have to...Your alternative would be to feed another wire from the alternator to the second battery directly... If you do not leave your stereo on, and you have same type batteries, you will really waste your money and decrease the charging system efficiency... Do what you think sounds good to you... :D
     
    peter_euro, Jan 30, 2003
    #3
  4. Slump_Da_Hustla

    Slump_Da_Hustla Full Member

    Well, thanks for both of your opinions...
     
    Slump_Da_Hustla, Jan 30, 2003
    #4
  5. cab

    cab Full Member

    I have the Stinger SR200 relay, and the only time I have voltage drop is when I'm stopped. It's fine when I'm moving.
     
    cab, Jan 31, 2003
    #5
  6. Slump_Da_Hustla

    Slump_Da_Hustla Full Member

    I can't find one anywhere. Guess I'll have to order one... :ph34r:
     
    Slump_Da_Hustla, Jan 31, 2003
    #6