Wiring up driving lights

[Magic1]

On my 82 Sierra k10 I've got a heavy duty wiring harness I bought and installed from another place that has the headlights running off a separate relay and the battery instead of completely through the switch itself.  I bought a set of Hella 55w driving lights and I have them run on separate grounds and I've tied them into the high beams of my headlights where they come on with the high beams as opposed to having their own switch.  They seem to work fine and I have no issues as of yet, I just want to see if anyone sees a problem with the way I have them set up so I can fix it in case there may be a problem with overloading the circuit. 

[bd]

Your basic concept is fine, but I would install a relay and switch between the high beam and driving light circuits to isolate them from one another and provide manual control in the event you don't want the driving lights to illuminate.  In addition, install independent circuit protection for the auxiliary lights in the form of a single 15-amp fuse [ 2 x 55 watts / 14 volts ≈ 8 amps].  Roughly, double the calculated current draw to determine adequate circuit protection.

Wire the relay coil in series with the switch, tapped into the high beam circuit for driving lamp control.  This will shift driving lamp load off of the high beam circuit.  Install driving lamp circuit protection between the relay and battery, and the lamps between relay and ground.

Edit: added image

[Magic1]

I appreciate the reply.  Do you think I'm overloading the circuit as is? I figured with the HD wiring harness on the headlights it would be able to handle the added load but wasn't sure. I don't see a reason to not have them come on when I'm running high beams and was trying to save having more underhood wire clutter from aftermarket add-ons. With the light relays and the dual electric fans I'm running it's starting to get crowded. Lol

[bd]

Two or four headlamps?

On a two headlamp system, the 55-watt driving lights double the load on the high beam circuit (100% increase).  On a four headlamp system, the same driving lights increase the load by roughly 50%.

Here's a grass roots approach to answering your question.  Wait until dusk or nightfall.  Point the truck at a light colored wall, about 10 - 15 feet away.  Cover the driving lights with an opaque hood to completely shroud their projection.  Now, start the truck and switch on the high beams.  While watching the light pattern on the wall, disconnect and reconnect the driving lights several times and notice whether the headlamp projection dims with the driving lamps connected.  If it does, the wiring is overloaded - perhaps not enough to risk damage (depending on the degree of dimming), but enough to impinge efficiency.  You could perform a more quantitative test measuring voltage drops across the harness if you like.  I prefer to isolate auxiliary lamps with a relay for greatest efficiency and to decrease the risk of losing all forward lamps in the event of a short, such as may result from an impact, corrosive salts or chaffed wiring.

Some locales regulate auxiliary lamps and require a switch to defeat function, either at the driver's discretion or as mandated by law.  Personally, I don't like oncoming glare so am very conscientious of other drivers.  If auxiliary lamp control is not mandated, it becomes optional.

[Magic1]

It's a four headlight system. I'll check out what you're saying with checking for dimness as soon as I get a chance. Again I appreciate it. I always make it a point to dim my lights when I meet someone but it just makes it much easier having them all come on together as opposed to having to switch on and off manually. That was my whole intention originally to have a super bright setup on high beams so I can see on backroads and spot deer easier.

[bd]

...it just makes it much easier having them all come on together as opposed to having to switch on and off manually.  That was my whole intention originally to have a super bright setup on high beams so I can see on backroads and spot deer easier.

You didn't track with what I was trying to express.  Wire the driving lamps so they turn ON and OFF automatically with the high beam dimmer switch - so they continue to operate the way you presently have them.  But also install a separate override switch, so you can force the driving lamps to remain OFF regardless of the dimmer switch and high beams.  In other words, if the driving lamp switch is OFF, the driving lamps are OFF.  But, if the driving lamp switch in ON, the driving lamps will illuminate only when the high beams are switched ON with the dimmer.  Does that make more sense?

[Magic1]

Yep. Gotcha now. I was thinking you meant having them set on a separate switch that would have to be alternated like the dimmer switch every time I dimmed my high beams

[Stewart G Griffin]

Read:
http://www.madelectrical.com/electricaltech/brighter-headlights.shtml