Hella 500 wire is hot 2 touch? help

wingysataday

Adventurer
I have 2 sets of Hellas' up front on my rig. one set is the 500ff and the other is just the 500's. I swapped out both sets with 100 watt bulbs. The red power wire coming from the battery will burn your fingers if you touch it. One of the fuse housings partially melted. According to Hella you can buy 100 watt upgrade bulbs for these. The hot wires running from the relay to the lights is not hot to the touch or even warm.
1. So why is it so hot?
2. If I just replace both the Red wires from the battery with heavier gauge wire and real in line mini IMG_2020.jpgIMG_2023.jpgIMG_2028.jpgfuses, to the relay will that be sufficient?
 

herm

Adventurer
what kind of relays? It may be that the relay is looking like a short to the battery when it is switched on. Do you have a wire diagram of your lighting system?
 

shmabs

Explorer
To mirror what herm said, we need to see an actual diagram of your wiring to make sure its correct, and posting up what guage wire you are running would also be helpful. To make a broad assumption, too small of a wire equals resistance in the circuit, and resistance can equal excessive heat. 100 watts seems like a lot for what appears to be relatively small wire based on the picture.

Mike
 

wingysataday

Adventurer
The wire is just whatever comes in the kit. The relay also comes with the kit. The 500ff have been hooked up for 2 years without any problems, the only change to them is the addition of the 100watt bulbs. The wire does seem to be a bit small 18guage maybe? Why wouldn't the the power wire from the relay be hot as well since it is only 18 guage . Thanks guys.
 
Last edited:

GTABurnout

Explorer
This is simple, the 100Watt light is pulling more power then your wire can handle. Get bigger gage wire or swap back to lower watt bulb. Or go HID.

Also per your picture I do not see seperat "hot" wire for each light. Are you running 4 lights off one small cable?
 

UK4X4

Expedition Leader
P=I*V
I=P/V

100W/12V =8.33 amps per bulb

4 lights thats almost 40Amps on a hot day.

So yep your positive wire from the battery is hauling amps

Check if your relay contacts can handle 40 amps

Probably better

runing 1 switch wire
using this for two relays- 1 for each set of lights run two postives one for each relay to the batteries- fused at 20 amps

Check your wiring distance/ ampage and choose the right wires- if in doubt go large !


http://www.windsun.com/Hardware/Wire_Table.htm
 

wingysataday

Adventurer
In the pic you can see 2 separate red wires with in line fuses so no, only 2 lights per relay and wire loom. If the Red wire coming from the battery is so hot to the touch than why is the black wire that goes to the lights from the relay no hot to the touch? The black wire is also 18 gauge.
 

wingysataday

Adventurer
UK4x4 how do I check and see if the relays are rated high enough? one of the relays says 40A on it so I am assuming it is 40 amps. The other is different.
 

wingysataday

Adventurer
Yellow from relay goes to the switch on the dash, red from relay to battery, blue from relay is ground, black is power from relay to lights.
 

shmabs

Explorer
what gauge wire is used on those fuse holders? looks rather small, and for 100 watts going through those lights, i would use 10 gauge to be safe!

Mike
 

wingysataday

Adventurer
Thats the problem with the inline fuse holders are 16 gauge wire. I'm just frustrated because these kits, say you can "upgrade to 100 watt bulbs." I will try these inline mini-fuses and see how it goes.
 

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