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Brian McVickers
07-28-2007, 04:12 AM
Hi gang!

I just acquired a set of Hella 3000 aux lights.

In preparation to wire them up I've been researching relays and they seem straight forward enough but:

What kind of relay should I use?
Relay with Resistor
Relay with Diode
Relay with Resistor and Diode
Relay with Dual 87 Integral Fuse
Dual SPST Relay

Also, if anyone has an idea of what size, in amps, circuit this should be you'll save my brain the calculation! The Hella 3000s have 55w bulbs.

In addition to these lights I have a CB and 2Meter wired direct to the battery as I believe they should be. I also have an Engel 45 powered through the 12v cig plug when I use it. Would it be more efficient to hard wire the fridge? Would a relay be involved here, should I be looking at creating a more complete system rather than adding individual relays one at a time.

Thanks

Brian :safari-rig:

HenryJ
07-28-2007, 01:49 PM
Some handy information:
Cable Gauge Selection Chart (http://www.crutchfield.com/S-PuGgc6psVgS/installguide/cable_gauge.html)
Wire Gauge Tables (http://www.rbeelectronics.com/wtable.htm) (This is the one I use the most , specifically the WIRE GAUGE SELECTION TABLE)

Basic Car Audio Electronics (http://www.bcae1.com/caraudio.htm)
the12volt.com (http://www.the12volt.com/)

the12volt.com has a wealth of information.

Relays: Special Applications (http://www.the12volt.com/relays/page5.asp)

Brian McVickers
07-29-2007, 03:16 AM
Where can I buy relays and switches?
I went to Autozone, Pep Boys, Napa, Checker, Radio Shack and Fry's Electronics -- Nothing!

The only thing I found was either a lightweight cheepo harness.

Any ideas?

goodtimes
07-29-2007, 03:25 AM
Where can I buy relays and switches?
I went to Autozone, Pep Boys, Napa, Checker, Radio Shack and Fry's Electronics -- Nothing!

The only thing I found was either a lightweight cheepo harness.

Any ideas?

If you want a complete harness, you can buy one from Wil (Sierra Expeditions). I used the Lightforce harness (from Wil) when I installed my aftermarket lights. The harness will work with any set of lights....and takes all the guesswork out of component selection. Kit includes wires, relay, fuse + fuse holder, SPST switch (non lighted), and instructions.

Brian McVickers
07-29-2007, 04:46 AM
I thought about that but I already have some wiring run through the firewall from teh old set of generic aux lights. The old set did not use relay so this will be an improvement. Running the wires through the firewall is a PIA so I'd rather not do it again.

Mike S
07-29-2007, 05:44 PM
Usually they will come with wiring, instructions, and a quality relay. There are several ways to set up your Hellas. Driving lights are often set up so that they only operate when the headlights are on, and set to high beam. They way, if you dip you lights, the driving lights go out.

It is relatively simple to set them up, using a I usually buy relays at a REAL auto parts store - not a chain - they overcharge - or switches, wire, and relays (power stuff in general), at a marine store. The marine stores usually have better quality components, like marine grade switches, wire, adhesive shrink wrap tubing, fuses, etc.

If you set your power system up with a dedicated power distribution block -separate from the battery - you're are going to find it easier to manage the wiring of accessories. This will allow you to locate a small blade fuse box near the power posts instead of having in-line fuses scattered around the engine compartment. It also simplifies the addition of accessories greatly.

Amp draw... Watts divided by volts = amp draw. check the wiring chart and select the next size larger than recommended in the amperage and wire run chart.

There is an excellent book on 12V systems by Miner Brotherton - The 12 Vot Bible for Boats - written for boaters, but very applicable to vehicles. Takes you from A to Z on 12V DC electrical systems.

Mike

Brian McVickers
07-29-2007, 07:59 PM
I just want a good brick and mortar retail source to buy swtiches and relays.

What is an example of a "REAL auto parts store"?

Thanks
Brian

Mike S
07-29-2007, 08:54 PM
I just want a good brick and mortar retail source to buy swtiches and relays.

West Marine.


What is an example of a "REAL auto parts store"?

Not Sherba's or Pep Boys. Try Napa.

Brian McVickers
07-29-2007, 09:29 PM
Thanks!

ntsqd
07-30-2007, 02:37 AM
From NAPA "Ignition and Electrical Systems Illustrated Part Guide", 2001:

p/n AR143 - N.C.-N.O.; resistor protected, plastic (?) mount tab

p/n AR204 - N.C.-N.O.; 20A, resistor or diode protected, plastic mount tab

p/n AR272 - N.C.-N.O.; 30A, resistor protected, "Open at 30A, Close at 20A"

p/n AR274- N.O. - 2 switched terminals; 30A, resistor or diode protected, plastic mount tab

p/n AR276 - N.C.-N.O.; 30A, resistor protected, metal mount tab, "Open at 30A, Close at 20A"

There's 52 pages of relays in that book, above are just a qwik sampling of Bosch pattern relays.

Brian McVickers
07-30-2007, 03:11 AM
Wow!
Napa does not even have one relay on their shelf other than OEM "Flasher" relays.

ntsqd
07-30-2007, 04:59 AM
Wow!
Napa does not even have one relay on their shelf other than OEM "Flasher" relays.
Plug those p/n's into their online page & see what you get.

HenryJ
07-31-2007, 12:21 AM
http://www.napaonline.com/

Lamp Relay - Fog & Driving (http://www.napaonline.com/MasterPages/NOLMaster.aspx?PageId=470&LineCode=GRO&PartNumber=448405&Description=Lamp+Relay+-+Fog+%26+Driving)

Item#: GRO448405

Price: $3.99
tax and shipping not included

Attributes:
Features & Benefits:30 Amp Relay
Guards Against Arcing & Overloads
Amp Capacity:30
Volt Rating:12

Ruffin' It
08-09-2007, 06:21 PM
2X on the West Marine route. Their stuff is good quality and there are plenty of options. On your Disco II there is a GREAT place to put a dedicated fuse block (a covered version that has 12 or so ports and is fused) that you can buy from West Marine. If you open your glove box and disconnect the hings so it swings all the way down, there is a perfect little space inside next to where the glove box sits when closed on the passenger door side of the opening. Additionally, there is a grommet right there on the firewall to pass the wires through from the battery without having to run them all over or expose them to heat and the elements. Just attach the fuse block with some good quality self-adhesive Velcro and you have a really nice and easy set-up and is secure and not an eye-sore. When it comes time to add more stuff, just pull the block out and attach the wires. No akward screws to take out and put back in.

It's worked really well for me - so far.


I just want a good brick and mortar retail source to buy swtiches and relays.

What is an example of a "REAL auto parts store"?

Thanks
Brian

jeffryscott
08-09-2007, 06:56 PM
Basspro also has this same piece, a 12 port Blue Sea relabeled for Bass Pro. I just picked one up (Blue Sea off the internet) and am about to install it ...


2X on the West Marine route. Their stuff is good quality and there are plenty of options. On your Disco II there is a GREAT place to put a dedicated fuse block (a covered version that has 12 or so ports and is fused) that you can buy from West Marine. If you open your glove box and disconnect the hings so it swings all the way down, there is a perfect little space inside next to where the glove box sits when closed on the passenger door side of the opening. Additionally, there is a grommet right there on the firewall to pass the wires through from the battery without having to run them all over or expose them to heat and the elements. Just attach the fuse block with some good quality self-adhesive Velcro and you have a really nice and easy set-up and is secure and not an eye-sore. When it comes time to add more stuff, just pull the block out and attach the wires. No akward screws to take out and put back in.

It's worked really well for me - so far.

adventureduo
08-09-2007, 09:10 PM
I have the blueseas dist. block. Works great.

http://img407.imageshack.us/img407/2619/2251302400034696539pqqgga3.jpg

You should be able to get relays and all the rest of the items you need at West Marine like they mentioned.. or there's cheaper (much cheaper) electronic stores. We have Orvac and Ford Electronics over here, i dont know what you have there. Go on superpages.com and see.

TJVach
08-09-2007, 11:11 PM
This might be a shot in the dark, but I have had AWESOME experiences with WaytekWire.com they have lots of wire there aren't expensive at all the only thing is that there are minimum order quantities. It worked really well for me because I have a lot of electrical projects that I have to do with my rig and I just have to buy once at a pretty decent price. Just my $.02

HongerVenture
08-13-2007, 06:49 PM
I understand relays and wiring for auxiliary lights and whatnot but I'm left with a question.

Let's use a set of auxiliary lights for example...
I have a switch wired(rated for 5A) to the relay as follows:

(+)--------(86) RELAY (85)----switch----Ground(-)

And I have the lights wired(rated for 30A) as follows:

(+)----fuse----(30) RELAY (87)----lights----Ground(-)

Do I need a fuse in the switch circuit? Or do you only bother to fuse the 30A lighting circuit?

ntsqd
08-13-2007, 08:45 PM
If you pull your 86 power from the 30 terminal then your fuse will protect both, although wired as you've indicated the load is the relay's coil so a short to ground after the 85 terminal just turns the lights on - not very likely to pop the fuse (BT, DT).

Just b/c the switch can handle 5A doesn't mean that the relay will draw that. I don't know off the bottom of my head what a relay does draw, but it's not very much.

HongerVenture
08-13-2007, 09:51 PM
If you pull your 86 power from the 30 terminal then your fuse will protect both, although wired as you've indicated the load is the relay's coil so a short to ground after the 85 terminal just turns the lights on - not very likely to pop the fuse (BT, DT).

Is that a standard shortcut? Pulling the power from the 30 for the 86? That's a great idea.


Just b/c the switch can handle 5A doesn't mean that the relay will draw that. I don't know off the bottom of my head what a relay does draw, but it's not very much.

I realize the relay probably draws very little current, however in the interest of over-design I'd make the circuit capable of handling 5A. The switch and wire gauge would be rated for that.

ntsqd
08-13-2007, 10:04 PM
Is that a standard shortcut? Pulling the power from the 30 for the 86? That's a great idea.

Don't know how std it is, it's my way of doing it.


I realize the relay probably draws very little current, however in the interest of over-design I'd make the circuit capable of handling 5A. The switch and wire gauge would be rated for that.
Absolutely no harm in a little over-design. :)

tacojosh
10-30-2007, 12:07 AM
I just cleaned up 2 years of wiring with this system:
http://i40.photobucket.com/albums/e211/angelastro/IMGP2861.jpg
http://i40.photobucket.com/albums/e211/angelastro/IMGP2858.jpg
http://i40.photobucket.com/albums/e211/angelastro/IMGP2855.jpg
http://i40.photobucket.com/albums/e211/angelastro/IMGP2866.jpg

tjbliley
10-30-2007, 09:28 PM
post up the source info for that. It looks sweeeeeet. I would like to get something just like it.

tacojosh
11-01-2007, 03:24 AM
post up the source info for that. It looks sweeeeeet. I would like to get something just like it.
www.4x4s-pod.com
http://i40.photobucket.com/albums/e211/angelastro/JK_sPOD_Kit.jpg
These are the connectors:
http://i40.photobucket.com/albums/e211/angelastro/spod-11.jpg

TeriAnn
11-01-2007, 04:37 AM
Where can I buy relays and switches?
I went to Autozone, Pep Boys, Napa, Checker, Radio Shack and Fry's Electronics -- Nothing!
The only thing I found was either a lightweight cheepo harness.
Any ideas?

I like wrecking yards for high quality relays. I discovered early 1990's Cadillacs use bosh relays with triple water seals and potted connectors.


http://www.expeditionlandrover.info/LR.images/GRrelayBosch.jpg

These relays would be sealed for short time immersion and impervious to just about anything that could be thrown at them in an engine compartment.

Cadillac uses a group of three that mount side by side on a simple metal bracket. I use one each for the horns, low beam, high beam and electric fan.

Cheap at the wrecking yard, high quality and about as water proof as you can get. Maybe not as fancy looking as rows of relays in a plastic enclosure, but far cheaper and probably better protected from water intrusion.

Mlachica
11-01-2007, 01:25 PM
Thanks teriann, those are nice relays. Out of curiousity, I wonder how much they are new. What model caddy's are they found in?

DaveInDenver
11-01-2007, 01:52 PM
Where can I buy relays and switches?
FWIW, a few places that I order misc electronic stuff:
www.waytekwire.com
www.mouser.com
www.digikey.com
www.rallylights.com
www.smallparts.com
www.terminalsupplyco.com
www.surplussales.com

DaveInDenver
11-01-2007, 02:02 PM
Thanks teriann, those are nice relays. Out of curiousity, I wonder how much they are new. What model caddy's are they found in?
I didn't know about the Bosch ones from Caddys, but Hella makes (and it might be the same relay inside the case, I dunno) something similar. I would expect that the junk yard ones would be just a couple of dollars?

The weatherproof base with pigtails is Hella 87173 (about $12, this is basically identical to TeriAnn's picture)
A weatherproof relay is Hella 87411 (about $8)
Just a simple skirted relay is Hella 87410 (about $5, this is like what TeriAnn's looks like)

ntsqd
11-01-2007, 02:30 PM
Add to Dave's list:
http://alliedelec.com/

http://www.delcity.net/

tjbliley
11-01-2007, 08:57 PM
Thanks