A little help with lighting question...

   / A little help with lighting question... #1  

sld

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Ford 1210 / Ford 1710
I thought about posting this in the owning / operating forum but I feel there are dedicated Ford experts here.

I have added 2 lights to the top of the roll bar on my Ford 1210. They are rated at 55 watts. First question, is that 55 watts per pair generally, or each?

I have a 35 amp heavy duty alternator according to the owner's manual and the only other lights are the factory head lights. I am not sure exactly what these are rated at but they are a standard twist in automotive style bulb and not near as bright as the auxilliary lights.

Second question is whether I am taxing my alternator by running all 4 of these or not. They way I have them wired is the lights on the roll bar don't get power until I turn on the factory headlights which are wired thru the key switch.

Just plugging in the numbers for worst case is 220 watts divided by 12 volts only equals 18.33 or so amps. I am using 16 gauge wiring for all.

Do you see any issues? At idle, the engine will slow down some when I turn them all on but at 1500 or more rpm's I don't notice anything.

Thanks for the advice.
 
   / A little help with lighting question... #2  
I thought about posting this in the owning / operating forum but I feel there are dedicated Ford experts here.

I have added 2 lights to the top of the roll bar on my Ford 1210. They are rated at 55 watts. First question, is that 55 watts per pair generally, or each?

I have a 35 amp heavy duty alternator according to the owner's manual and the only other lights are the factory head lights. I am not sure exactly what these are rated at but they are a standard twist in automotive style bulb and not near as bright as the auxilliary lights.Thanks for the advice.

55 watts each.
 
   / A little help with lighting question...
  • Thread Starter
#3  
Thank you Mr. Brown.

That is what I thought but wasn't sure.
 
   / A little help with lighting question... #4  
I thought about posting this in the owning / operating forum but I feel there are dedicated Ford experts here.

I have added 2 lights to the top of the roll bar on my Ford 1210. They are rated at 55 watts. First question, is that 55 watts per pair generally, or each?

I have a 35 amp heavy duty alternator according to the owner's manual and the only other lights are the factory head lights. I am not sure exactly what these are rated at but they are a standard twist in automotive style bulb and not near as bright as the auxilliary lights.

Second question is whether I am taxing my alternator by running all 4 of these or not. They way I have them wired is the lights on the roll bar don't get power until I turn on the factory headlights which are wired thru the key switch.

Just plugging in the numbers for worst case is 220 watts divided by 12 volts only equals 18.33 or so amps. I am using 16 gauge wiring for all.

Do you see any issues? At idle, the engine will slow down some when I turn them all on but at 1500 or more rpm's I don't notice anything.

Thanks for the advice.

No Ford expert needed to answer this question...it basic Ohm's law.

Your two "extra" lights are rated at 55w each, not a pair-so they draw just under 8 amps @ 13.8 volts. Your headlights are probably 35 watts each (you can verify by checking the bulb number) so they draw just over 5 amps @ 13.8 volts

So I figure your drawing about 14 or so amps when all four are on with your 35 amp alternator...you are fine.
 
   / A little help with lighting question...
  • Thread Starter
#5  
Thank you KennyD.
 
   / A little help with lighting question... #6  
One thing I would be a leery of. You said you are running these through the original factory switch. Are you using a relay? If not, is the switch heavy enough to carry the added load of these lights?
 
   / A little help with lighting question... #7  
Ditto that.. I'd use that key switch to power a relay, that carried the lamp power.

real easy to change over.. the wire from the key going to the lamps.. just have that feed the coil of one of them 30a fog lamp relays.. ground the other side of the coil, then run bat power to one of the NO contacts, and the other NO contact picks that wire back up to the lamps.. probably take ya 5 minutes to connectorize it together..

soundguy
 
   / A little help with lighting question... #8  
...and if the below means you are running the combined load of 2 new and 2 OE lights on 16 ga wire, I would think about upping that to at least 14 ga.

"Just plugging in the numbers for worst case is 220 watts divided by 12 volts only equals 18.33 or so amps. I am using 16 gauge wiring for all."

RavensRoost
 
   / A little help with lighting question...
  • Thread Starter
#9  
One thing I would be a leery of. You said you are running these through the original factory switch. Are you using a relay? If not, is the switch heavy enough to carry the added load of these lights?

I have wondered about that also. I think I might wire the aux lights straight from the battery to the toggle switch that powers them. That leaves what was factory intact and the stuff I added separate. This will also cut the amperage in half for the marginal wire gauge.

Still think I need a relay? The metal toggle switch should be fine for 1 set of lights.

Thanks for the advice.
 
   / A little help with lighting question... #10  
The relay is a good idea IMHO. The "trigger" to the relay can be from a source that's only hot when the key is ON, that way the lights will not operate with the key OFF.

Check the rating on any switch you add, but most auto style toggles are rated for 20 amps.

Here is basically how I wired mine:
 

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