Relay
+ Reply to Thread
Results 1 to 10 of 10

Thread:
Relay

  1. #1
    I'm No Expert Shaun's Avatar
    Join Date
    Feb 2008
    Location
    San Clemente, Ca
    Posts
    3,138

    Default Relay

    I bought a few relays for things like fuel pump, bilges, and the banderlog. They are a 30 amp relay but i'm curious what guage wire i need to feed the on/off side. I'm thinking a 18 guage wire should be enough.

    Specs off the relay
    Coil Voltage: 12V
    pull-in Voltage: 6V
    Coil resistance: 66 ohms
    Nominal current: 160mA
    Drop-out voltage: 3.6
    SPST contacts: 30A at 12VDC

    Is nominal current the amp usage of the coil side of the relay?

  2. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  3. #2
    Senior Member 2002CP19's Avatar
    Join Date
    Jun 2008
    Location
    Lake Arrowhead/Lost Lake
    Posts
    692

    Default

    Quote Originally Posted by Shaun View Post
    I bought a few relays for things like fuel pump, bilges, and the banderlog. They are a 30 amp relay but i'm curious what guage wire i need to feed the on/off side. I'm thinking a 18 guage wire should be enough.

    Specs off the relay
    Coil Voltage: 12V
    pull-in Voltage: 6V
    Coil resistance: 66 ohms
    Nominal current: 160mA
    Drop-out voltage: 3.6
    SPST contacts: 30A at 12VDC

    Is nominal current the amp usage of the coil side of the relay?
    If this will ever see a 30 amp load you want to use 12 or 10 for that matter. 18 gauge will get HOT with 10 amp loads 30 will be BAD!

    I think I read it wrong, the signal side of the relay can be run in 18 gauge with no problems but the load side needs to be sized according to the amp load.

    Brandon

  4. #3
    Senior Member Futs's Avatar
    Join Date
    Dec 2007
    Location
    Orange CA, Big River
    Posts
    4,549

    Default

    12 guage minimum.

  5. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  6. #4
    steelcomp was here
    Join Date
    Dec 2007
    Location
    n/e TN
    Posts
    26,351

    Default

    Quote Originally Posted by Wanna_be_CP View Post
    If this will ever see a 30 amp load you want to use 12 or 10 for that matter. 18 gauge will get HOT with 10 amp loads 30 will be BAD!

    I think I read it wrong, the signal side of the relay can be run in 18 gauge with no problems but the load side needs to be sized according to the amp load.

    Brandon
    Correct. The coil side isn't even pulling an amp and 18G would be plenty. ON the load side, it depends on the load. Typically, 15a or lower use 14g, 20a use 12ga, and 30a use 10ga.
    If God is your co-pilot, change seats!
    Acts 2:38, the perfect answer to the perfect question.

  7. #5
    Banned
    Join Date
    Jan 2008
    Location
    El Cajon, CA.
    Posts
    3,605

    Default

    Quote Originally Posted by steelcomp View Post
    Correct. The coil side isn't even pulling an amp and 18G would be plenty. ON the load side, it depends on the load. Typically, 15a or lower use 14g, 20a use 12ga, and 30a use 10ga.
    X3

  8. #6
    I'm No Expert Shaun's Avatar
    Join Date
    Feb 2008
    Location
    San Clemente, Ca
    Posts
    3,138

    Default

    I'm talking about the gauge needed to feed the on/off switch side... the side that a switch usually hooks too to activate the relay. Sounds like 18g is fine for that.

  9. #7
    Banned
    Join Date
    Jan 2008
    Location
    El Cajon, CA.
    Posts
    3,605

    Default

    Quote Originally Posted by Shaun View Post
    I'm talking about the gauge needed to feed the on/off switch side... the side that a switch usually hooks too to activate the relay. Sounds like 18g is fine for that.
    Yep, that's correct. You could go with a much smaller wire but I wouldn't recomend it in a boat just so there's strength to the wire.

  10. #8
    I'm No Expert Shaun's Avatar
    Join Date
    Feb 2008
    Location
    San Clemente, Ca
    Posts
    3,138

    Default

    Quote Originally Posted by hotrod56cars View Post
    Yep, that's correct. You could go with a much smaller wire but I wouldn't recomend it in a boat just so there's strength to the wire.
    I doubt i'll run 18 to them, probably 16... I always take what they recommend and step it up. Example, autometer recommened 18 for there guages between the sender and the guage... I ran 16. Just makes me feel alittle better.

  11. #9
    Banned
    Join Date
    Jan 2008
    Location
    El Cajon, CA.
    Posts
    3,605

    Default

    Quote Originally Posted by Shaun View Post
    I doubt i'll run 18 to them, probably 16... I always take what they recommend and step it up. Example, autometer recommened 18 for there guages between the sender and the guage... I ran 16. Just makes me feel alittle better.
    Whatever you're comfortable with that'll work is good. I've used as small as 24 gauge wire to trigger relay's.

  12. #10
    Senior Member ap67et10's Avatar
    Join Date
    Mar 2008
    Location
    Chico, Ca
    Posts
    1,533

    Default

    your talking about the control circuit of a relay, you can use 18 gauge if you want, your could even use smaller if you wanted, but i also like to go just slightly bigger because of the distance the current must travel from the front to the rear which is why i think 18 is perfect. but the load that it takes to control the relay would be like 1 of the bulbs for your gauges, its next to nothing. the reason why they are so so much safer than running it straight to a switch. i still can't figure out why anyone would think to run anything directly to a switch....everything on my boat has a relay. i've seen a boat on fire and you have absolutely nothing when its over...nothing. not worth it.

    AP

+ Reply to Thread

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.

Please enter a password for your user account. Note that passwords are case-sensitive.

Please enter a valid email address for yourself.

Please select your insurance company (Optional)

Log-in


Tags for this Thread

Digg This Thread

Posting Permissions

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
  •  
 

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95