would four 6" light draw too much power?

[MossyOakRam]

I just made a back rack for my truck and i want to put four 6inch diameter driving or fog lights on top of the rack i think they are navigator brand fairly inexpensive , i am wondering if they will draw too much power from the truck when the four lights are on and my headlights/high beams too

 

[RamRod37]

I just made a back rack for my truck and i want to put four 6inch diameter driving or fog lights on top of the rack i think they are navigator brand fairly inexpensive , i am wondering if they will draw too much power from the truck when the four lights are on and my headlights/high beams too

you will need to use a relay for sure even if they are only 55 watts each that's 220 watts and 18.33 amps regardless if they are on your headlights or separate switch

 

[WhiteExpress]

You truck will be able to handle the additional load no problems.
Just make sure you wire them properly.

 

[MossyOakRam]

If i do need a relay how do they work are they expensive?

 

[RamRod37]

If i do need a relay how do they work are they expensive?

A relay Is Usually 10-15 bucks A Relay Allows Device To Be Powered straight from battery and the switching device say the headlights high beams in you case only switch's the relay keeping the entire load on battery not the headlight switch

and I would Wire A Second Switch in cab so you can turn them off so you can use your high beams without the high mount lights cause they are Illegal on all roadways/highways off road would be the only legal time they could be used

You only need a 4 post relay but 5 post will work fine just one post will not be used on the 5 post
post
30 12v battery
85 ground
86 12v high beam wire
87 to add on lights

post 85-86 does not matter which one is ground and which one is 12 volt high beam and the 5 post relay will have a post 87A which in you application will not be used

 

[MossyOakRam]

My plan was to wire them directly to the battery and wire all 4 lights to a seperate switch that comes with the lights

 

[RamRod37]

My plan was to wire them directly to the battery and wire all 4 lights to a seperate switch that comes with the lights

ok I would still use a relay cause theres a lot of switchs out there that not rated high enough amperage to work long before switch burns up

relay would wire as follows
post
30 battery 12v
85 ground
86 from switch 12v
87 to your lights added

this keeps the load off switch

This will allow you to use a bigger selection of switchs

 

[WhiteExpress]

You also need to consider running the right gauge of wire for the length of run you will have.
Sure a 18 ga wire might work for a few minutes, over a 3' run.
You start talking 10-15' of wire, it can get hot quick, causing poor performance of the lights (dim) and fire hazards.

The main point of a relay is to keep the high levels of current isolated from the switch, as well as shorten the length of heavy (expensive) wire needed.

You could run one heavy (think 10 gauge) wire to the bed and put in a relay center there.
A pair of 30 Amp relays should do fine. Wire a pair of lights to each relay.
This would make for only once heavy / expensive wire running from the battery to the bed of the truck.

Something to think aboot.

 

[RamRod37]

You also need to consider running the right gauge of wire for the length of run you will have.
Sure a 18 ga wire might work for a few minutes, over a 3' run.
You start talking 10-15' of wire, it can get hot quick, causing poor performance of the lights (dim) and fire hazards.

The main point of a relay is to keep the high levels of current isolated from the switch, as well as shorten the length of heavy (expensive) wire needed.

You could run one heavy (think 10 gauge) wire to the bed and put in a relay center there.
A pair of 30 Amp relays should do fine. Wire a pair of lights to each relay.
This would make for only once heavy / expensive wire running from the battery to the bed of the truck.

Something to think aboot.

The relay Wired under hood only requires one wire to back a #10 gauge wire from relay 87 to lights a ground may be run off frame at bed cab straight up to lights
#10 Gauge wire from battery to post 30
85 86 posts can be as small of a wire down to 16-18 gauge for relay switching

And Two relays Is Not Necessary and a waist of money and time unless you plan on switching then 2x2

One Relay under hood with a 20 amp circuit breaker or fuse between battery and relay is all that's needed
20 amp providing the lights are only 55 watt if not take total watts of the four lights and devide by 12 that will give your amperage and size fuse needed just make sure relay has the same rating or higher

 

[myoung84]

ok I would still use a relay cause theres a lot of switchs out there that not rated high enough amperage to work long before switch burns up

relay would wire as follows
post
30 battery 12v
85 ground
86 from switch 12v
87 to your lights added

this keeps the load off switch

This will allow you to use a bigger selection of switchs

X2 on this.

Make sure the wire(s) from the battery to the relay(s) are fused. You didn't mention what lights you'd be using, but a 100 Watt halogen light is about 7 Amps at 13.8 Volts, a 55 Watt would be about 4 Amps (Watts/Volts=Amps). You could use a standard 30/40A relay for all four lights even on the 100 Watt lights.

For the wire size, it really depends on the distance of the run and where you mount the relay. If mounting a single relay under the hood, I would use a 10 gauge wire from the battery to the relay then two parallel 10-12 gauge wires (depending on distance) from the relay to the lights (two lights per wire). If using two relays, still use 10-12 gauge to each relay and a single 10-12 gauge from each relay to light pair. This assumes you are using 100W lights, in which I would recommend two relays. One relay and a single 10 gauge wire would be fine for 55W lights.

Here's a pretty good chart for figuring wire sizes...

 

[MossyOakRam]

these are the lights they are 55 watt 12v

 

[MossyOakRam]

they come in pairs with a switch included, would it be better to have 2 switches inside the truck for example have one switch for the outter lights and the other switch for the inner? im not to bright when it comes to electronics and wiring and stuff with the relays lol

 

[RamRod37]

these are the lights they are 55 watt 12v

You could do it with two if you wanted to have them on two switchs they would have to be rated 10amps or higher per switch or 20amp for using a single Switch If done this way I would still use a 20amp fuse at battery I highly
Recommend Against doing it this way but your choice you will have more Issues
with switchs

I highly Recommend you stay with the relay route I talked about we will help you anyway we can to get you hooked up right through the relay they are not hard to do after you do this one it will come easy to you

 

[RamRod37]

Pictures of a 4 post relay 5 post the same with one more post 87a not used can use both

 

[RamRod37]

Post Number and color Circled in pic
30 12v battery/yellow
85 ground/green
86 12v from switch/blue
87 to lights/Red

 

[MossyOakRam]

That makes things more clearer ill try and tackle this lil project next week ill try the relay