Here's a Hella one (part no. HL87483 ):

Hella HL87483 Mini Relay, 12V, 40A, SPST, Dual 87 Pin | Rally Lights

 

Yes, I did see this one before. Have you found this exact configuration with a built in fuse? The Narva brand that you posted before appears to make a dual 87 out with a fuse. Are they available in the US?

 

Sorry if I confused you M-007, but NARVA don't make a fused dual pin 87 relay, the one's I have used are single output with a joiner or double headed crimp connector, something like this:



You can find NARVA products on eBay, however your local auto-shop should carry a brand that is a little cheaper and easier to supply. NARVA is a brand that is readily available for us down under so I refer to it, but because we live out of town I tend to buy things like relays and crimp terminals in bulk on line.

Reference:
Normal Open 4 & 5 - Products - Narva
Fused - Products - Narva
Narva Relay | eBay

 

Understood. I guess I'll just go with the normal 4-pin fused relay and run both lights off the single 87 pin. Or I could just have 1 really for each. Another question...Would you happen to know what color wire is the low beam + coming out of the headlight connector?

 

This should be the same as yours - but KIA do change things depending on age and location:





So the low beam is Green wire 0.5mm coming off pin 3, left and right are the same pins and color. Note that there are no fuses, its an IPS system as well.

 

Great! I guess the best way to go then is tap off the low beam (green) and drive 1 side of the relay as you noted with 2 wires coming off pin 87. If the bulbs are 27 watts each then a 30A relay would be plenty. I assume 1 relay for each bulb would be overkill??

 

The 27w is the original fog bulbs, so that's between 2 and 2½ amps per fog line being drawn down, total 4 to 5 amps thru the relay contact (pins 30/ 87) if you were going to stay at that size. So yes a single 30amp relay would handle it okay.

A 12v relay coil (pins 85/86)will draw between 100 and 300mA so by tapping this into the low beam line you are increasing the current draw of that low beam by this amount.

Low beam bulbs are 55w, about 4 to 4.6amps, so increasing this load by another 100-300mA is pretty significant, but without the relay you are adding almost 50% more current drain on the low beam circuit, this is why we say it is always better to go that extra step in adding a relay.

If you have wired the contact side of the relay (pin 30/87) to the battery and load (via a fuse) you can increase the light power up to about 180w each side and still remain in spec on the relay heavy duty contacts(30/87) and the coil side(85/86). Of course the wires from that battery need to be rated accordingly to cope with this load.

 

Thanks Barri... So, assuming a stock setup remains there will be no problem down line. Now, I'm still curious as to whether you feel that a relay for each fog light is overkill and not worth the extra wiring effort?

 

Personally I think its a bit of over-kill. It's not as if you are drawing a lot of current or that it is an essential accessory (is there such a thing as an "essential" accessory ?), so unless you feel like doing extra work - and introducing more points of failure - there is nothing wrong with just one relay.

 

OK. If I go with the dual 87 pin Hella relay I will need an in-line fuse I am assuming. What rating should this be? 40A to match the relay or something less?

 

The fuse rating is to match the load you are pulling, i.e. if you are installing two 27w lamps, the current draw (load) is these two combined (54w).

Power(P) in watts is calculated as voltage(V) times current(I) in amps; [P=VxI], so to work out the current we divide the power by the voltage.

So this gives 54w÷12v = 4½amps (the car's voltage will change depending on revs and battery condition etc. , i.e. if you calculate using 13.5v the current works out at 4amps, 0.5 amps less, 11.5v is 4.7amps)

Fuses come in different current ratings so in our case we'd be looking at fuses in the range between 4, 5, 7½, or 10. I would use either the 7½ or 10 amp depending on what I had handy, doesn't matter that it's a bit more, however 4 is definitely too small, and 5 is cutting it fine if your voltage drops below 12v (say at idle or if the motor is off).

BTW the 40amps of the relay is the maximum the contacts of the relay is designed to take, so whilst you can use it on your twin 27w fog lights, this same relay with a 40amp fuse can handle twin spotties of up to 240w each (480w total) at 12v. You would need to make sure all other components in the system were also suitably upgraded especially the wiring and connectors/terminals.