Spyder headlamps.....my take on 'em...and LIGHTING in general

[shovelbill]

i checked the tester on a motorcycle battery i just put on the tender....the battery just clicked the 80% charge light....was at 11.9V.

 

[shovelbill]

The best way to measure voltage drop is to measure both the positive and ground conductors separately, with a volt ohm meter.

Add both figures together, and you will get the total voltage drop. Are you backprobing the connector with the headlamp lit?

Edit: I can see you are plugged into the harness connector in the second picture.

Best practice is with the lamps lit... backprobe the connection with a paperclip or tool made for this.

LOL....after i did this i remembered a post you made on how to do it correctly......that's a job to do in the morrow......i'm going to put in the other Spyder and "stab" into the connectors. that's why i bought this expensive little device, right?

 

[michael hurd]

From just the figures you posted, you have a roughly 9% drop in voltage in one wire, the positive wire. Adding them together, if the ground also has a 9% drop would net 18% drop over your charging voltage.

14.4 x 0.82 - 11.808V, and that is in good agreement with what I got on my truck.

EDIT: Basically, about 75% brightness, compared to 12.8 volts at the headlamp when lit, more if 14.4V at the headlamps.

 

[shovelbill]

the fact that that the switch and runs of wire gobbled up .8v(low) and 1.2v(high) shows a simple difference on it's own......we'll get definitive numbers tomorrow.......then after the harness is in we'll do the procedure once again to see what we gained.

 

[michael hurd]

V drop measurement:

http://www.danielsternlighting.com/tech/relays/relays.html

 

[shovelbill]

here's a pretty good video......

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[shovelbill]

V drop measurement:

http://www.danielsternlighting.com/tech/relays/relays.html

You must be registered for see images attach

 

[michael hurd]

Good. Now you are equipped to measure both the ground resistance and the resistance of the positive wire. What you were measuring ( with tester on battery negative ) was only the resistance in the positive wire.

You have to take the ground return path into consideration as well, and measure both with the headlamps lit.

This gives a much more accurate picture.

 

[shovelbill]

Good. Now you are equipped to measure both the ground resistance and the resistance of the positive wire. What you were measuring ( with tester on battery negative ) was only the resistance in the positive wire.

You have to take the ground return path into consideration as well, and measure both with the headlamps lit.

This gives a much more accurate picture.

i've learned a lot from you......you've thrown the stick, i spent days chasin the [email protected]

i did say electrical wasn't my strong suit.......but i can wire a house....LOL.

 

[michael hurd]

i've learned a lot from you......you've thrown the stick, i spent days chasin the [email protected]

i did say electrical wasn't my strong suit.......but i can wire a house....LOL.

On old houses that had knob and tube, and / or 2 wire outlets, then someone tied in and put 3 wire outlets, gotta watch out for reversed hot - neutral bootleg ground outlets..... they can be deadly, and a 3 light tester will not pick up this dangerous condition.