| Author |
Message |
Nick Morris (Nick3751) (65.117.139.135)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, April 05, 2004 - 7:36 am: | |
Can anyone tell me where I can find a chart or something that can give me the size wire I need for voltage for a particular distance for 12v.
I'm redoing the chasis system on my silversides and most of the relays are dead so I'm planning on running the wire strait from switch to whatever it works. I don't even know if there is any voltage drop with 12v so I may not need to do this but I thought since I was running about 45 feet of line I'd check before I bought the wire.
Thanks to all. |
BrianMCI96A3 (69.68.102.7)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, April 05, 2004 - 9:16 am: | |
Actually Nick, probably the single biggest reason we do not all use DC in our homes is the voltage drop with distance inherent in DC circuits.
Having said that, the size of the conductor you'll need is dependent on how much amperage you wish to run through it. A wire that will see a miliamp draw over 35 ft does not need to be very big at all, but one with a 50 amp draw over 35 ft needs to be huge. There are tables that will tell you, but you do need to have a good idea what the amperage of the circuit will be.
Brian |
CoryDane RTSII (66.155.188.226)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, April 05, 2004 - 12:14 pm: | |
I noticed the chart you are referring to in the West Marine catalog.
Lucky for you, West Marine has a catalog ON LINE!
http://mastercatalog04.westmarine.com/0660.asp
Hope this helps
"Imagine"
cd |
DaveD (142.46.199.18)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, April 05, 2004 - 3:45 pm: | |
Current is what needs to be considered when selecting wire sizes. One of the reasons for using relays is to enable switching of circuits where the current is high. By using a relay, the size of the conductors and the rating of the switch which controls the relay can generally be reduced since this part of the circuit is only handling the relatively low current through the relay coil. An appropriately rated relay can then be used to handle the (generally greater) current being switched. Control circuits to relays can use lighter gauge wire and the relays can be located closer to the devices to be operated. In this way a single large gauge conductor can be run from the battery source to a panel of relays and then appropriate gauge wires can be run from the relays to the devices to be operated.
I would recommend that you shouldn't directly connect the circuits which were relay controlled to switches; rather you should replace the dead relays with newer ones with equivalent ratings.
FWIW |
Nick Morris (Nick3751) (65.117.139.135)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, April 05, 2004 - 8:06 pm: | |
At some point in the past my rig has had everything cut out at both ends and is currently running on a "direct wire" approach. Although I've thought about replacing the relay that would only be one more thing that could fail. |
BrianMCI96A3 (69.68.102.7)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, April 06, 2004 - 8:37 am: | |
Nick, while that sounds like it will simplify things, unfortunately in the long run you will be carrying a load through your switches that they were never meant to carry, you would be lucky if all this caused was a few burned out switches.
Relays, as mentioned before are meant to handle much larger loads than most switches, and work repeatedly for years, you never know, your relays may actually still work.
In the end, I believe you are asking for a great deal more headache down the road if you do not use relays in circuits that call for them. |
Nick Morris (Nick3751) (69.69.38.3)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, April 06, 2004 - 9:12 am: | |
That's why I like this board. I'm pretty limited when it comes to the more advanced wireing (at least in my opinion). I can handle wireing a set of lights and a few gizmos but this is a little over my head.
I'll be checking those relays tonight I think. That will end up being cheaper running smaller wire 45ft long. Cool deal thanks all!!!!!! |
joe shelton (64.223.175.242)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, April 06, 2004 - 12:14 pm: | |
go to http://www.amplepower.com/pdf/index.html
and select ample power primer. there you can select wire_gauge.zip and save the pdf file to your computer.
ample power is one of the best to get 12vdc info. |
Nick Morris (Nick3751) (65.117.139.135)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, April 06, 2004 - 7:43 pm: | |
Good deal, I just tested the started, reverce and the starter cutout relays and they're all good. Sooooooo as soon as I get the wires back to the engine compartment they'll be getting hooked back up. |
BrianMCI96A3 (69.68.102.7)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, April 06, 2004 - 9:47 pm: | |
That's great Nick, glad to hear that the relays were still good.
Brian |