LED amp draw and lighting output

[CalG]

How much light can I get with the LED work lights with only 5-7 amps to play with?

When I look at the commercial offerings, It seems like the adds play with the words and specs.

I've got on old tractor (1950) with a Lucas generator, and would like to keep the battery up even when the Western snow plow hydraulic motor is used .

 

[FTG-05]

5 amps x 12 vdc = 60 watts
60 watts x 50 lumens/watt = 3000 lumens +/-


7 amps x 12 vdc = 84 watts
84 watts x 50 lumens/watt = 4200 lumens +/-


I just picked the 50 lumens/watt out of the air. You might find more efficient LED lights.

For example, here are some 77 lumen/watt LED work lights that draw only 2.3 amps at 12 vdc: Maxxima Rectangular LED Work Light, 2,150 lumens | AW Direct

 

[CalG]

Yes, I know how to calculate watts.

It seems the LED light purveyors have different ideas about the math. ;-)

The link you have referenced is interesting, but quite spendy for a work light.

 

[Dave M7040]

Could it be with a 1950's tractor you are talking about a 6 volt system not a 12 volt?

Have you considered upgrading by installing a Delco alternator. I have done it as have many others on all sorts of vehicles.

Dave M7040

 

[CalG]

Could it be with a 1950's tractor you are talking about a 6 volt system not a 12 volt?

Have you considered upgrading by installing a Delco alternator. I have done it as have many others on all sorts of vehicles.

Dave M7040

12v, positive gnd. system. With a 5L fan belt. Getting a delco with a pulley this wide might be a problem.

 

[Dave M7040]

12v, positive gnd. system. With a 5L fan belt. Getting a delco with a pulley this wide might be a problem.

Below is a link to a company making alternators and pulleys to fit the 5L belt.

Alternator Mounting Brackets & Tractor Generator to Alternator Conversion

This is the pulley you can buy without an alternator that will work with the 5L belt which is 21/32" wide.

In looking at the spec's for a 5L belt and a B or BP belt, the belt cross sectional dimensions are identical.

The B series belts are designed to transmit more power than the 5L

https://www.gates.com/~/media/files...mission/chart/gatescorporationbeltidchart.pdf

In summary I don't think the conversion is hard to do and then you will have lots of power and much better reliability than Lucas could ever offer.

Dave M7040

 

[Soundguy]

Could it be with a 1950's tractor you are talking about a 6 volt system not a 12 volt?

Have you considered upgrading by installing a Delco alternator. I have done it as have many others on all sorts of vehicles.

Dave M7040

He said Lucas.. Its going to be 12v

 

[Dave M7040]

I am sorry but I fail to get your point. Plse clarify.

I accepted the owner's statement that his machine had a 12 volt positive ground. If the alternator truly dates to 1950, then the output must have be very low perhaps 11 amps

The positive ground is the challenge when changing alternators but not insurmountable.

Currently with only 5 to 7 amps available, he is running a electric hydraulic snow plow and now wants more lighting.

It was not clear about the 5-7 amps being an available output surplus after the plow unit is considered.

Dave M7040

 

[Tractor Seabee]

May be time to run a new circuit for new lights. Go 15 amp circuit and you have plenty of work lights. Double check your generator/alternator voltage output.

Ron

 

[CalG]

May be time to run a new circuit for new lights. Go 15 amp circuit and you have plenty of work lights. Double check your generator/alternator voltage output.

Ron

Oh If only there were an extra 15 amps available.

Will placing a 15 amp fuse in the circuit miraculously make the current appear ;-)

I think the original post made clear that there are few "extra amps" available.

 

[Tractor Seabee]

Sorry, I assumed you had added up existing actual amp draws or checked with an ammeter and had enough output, just not a heavy enough circuit available. Fuses are sized for the wire size not the connected load. Forgive me for taking a shot gun approach instead of a scoped rifle.

Ron

 

[CalG]

Your assumption is correct! I've got 5-7 amps to play with , and even that is at the expense of recovery time for restoring the battery after exercising the snow plow lift or angle.
I'm just going by the amp meter that is installed in the circuit. ( I put it in myself! ;-)

I'm sure the battery has life enough to cope with the loads , but hanging the charger on all winter is annoying.

Have you any experience with these new fangled LED work lights? for upwards of a $100, it appears 3 amps will buy one a lot of light.

 

[Tractor Seabee]

No experience with the low voltage ones. I am planning some upgrades to my equip trailer this winter and will use them. We moved to another house 3 months ago. Replaced all the lamps with LED and added 7 new LED fixtures to the garage. Power bill is already down $25 form last month.

Ron

 

[CalG]

No experience with the low voltage ones. I am planning some upgrades to my equip trailer this winter and will use them. We moved to another house 3 months ago. Replaced all the lamps with LED and added 7 new LED fixtures to the garage. Power bill is already down $25 form last month.

Ron

All LEDs run on 3-6 volts "in the raw" I've put LED lamps around the house for night lights,
I need to recover from the florescence "save the world" craze before buying into the LED home lighting idea.

The charge real money to dispose of "hazardous materials" like fluorescent bulbs!

But my interest is in tractor lighting. LEDs in particular. ;-)

 

[Dave M7040]

No experience with the low voltage ones. I am planning some upgrades to my equip trailer this winter and will use them. We moved to another house 3 months ago. Replaced all the lamps with LED and added 7 new LED fixtures to the garage. Power bill is already down $25 form last month.

Ron

18 wheeler owners and drivers with LED lighting on the trailer find, in snowy conditions, the lights get completely obscured by snow.

With the incandescent bulbs, there was enough wasted heat to keep the snow off.

Dave M7040

 

[Soundguy]

I am sorry but I fail to get your point. Plse clarify.

I accepted the owner's statement that his machine had a 12 volt positive ground. If the alternator truly dates to 1950, then the output must have be very low perhaps 11 amps

The positive ground is the challenge when changing alternators but not insurmountable.

Currently with only 5 to 7 amps available, he is running a electric hydraulic snow plow and now wants more lighting.

It was not clear about the 5-7 amps being an available output surplus after the plow unit is considered.

Dave M7040

It's a generator from the 50's, and polarity is a NON issue. Also.. amperage will likely be in the 20-25a range... probably 20a.

 

[GLyford]

I have a couple of 18W LED lights on my garden tractor, and run them off the motor AC light circuit (5A) through a diode bridge (light circuits route back to the bridge rather than ground directly). 5A runs the lights fine. The only thing I haven't done so far is...needed to run it at night!

 

[moship]

After measuring 3 different styles of LED work lamps, I found the rated watts to be overstated. Therefore the OP should be able to get plenty of light with 5 amps.

The 18 watt lamps were of a 1x6 led arrangement (1 row of 6 leds), 27 watt has 9 leds in a 4.5 square housing and the 36 watt units have 12 leds mounted in 2 rows or 6 leds.

Claimed Watts----Actual Watts----Amps per work light----# of LEDs
------18-----------------9.5----------------0.75-------------------6
------27----------------14.5----------------1.18-------------------9
------36----------------26.0----------------2.06------------------12

Keep in mind the values above are per work light, so if mounting a pair the amperage would be doubled.

The LED's lights above were the cheap (under $25 for a pair) and bought off Amazon.

All of the above put out an amazing amount of light when compared to halogen headlights or conventional work lights.

 

[CalG]

Thanks for these data points! Above and beyond!

See what I mean about the confusing "specs" associated with commercial LEDs. Is it "More is better" marketing? or just the expected amp draw at Maximum applied voltage? ... hard to tell.

 

[coldsteelva]

LED lamps, even multiple lamps should never be able to draw more power and blow a fuse that was originally spec'd. for an incandescent. I imagine you would have too much light and go blind before the fuse would let go. Alternatively, I recommend running a low voltage/amperage/wattage switch to a relay direct connected to the battery. It will be fused separately and even if your lights blow, you won't harm the main electrical of the tractor.