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Rock lights --- Wiring troubleshooting

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#22 ·
Trons said:
I'm betting on this. The lights are probably like xmas lights, where they look like they're in series, but really aren't that way if one blows, it doesn't take everything else out with it.
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See, now here we go. Christmas lights used to be wired in series and the string would quit working when one burned out. You would have to rob a known good from a lit up string and replace each bulb in the dead string one by one until you found the bad one and the string lit up again. What was really fun was when two burned out at once. :rofl:
 
Discussion starter · #24 ·
2jhanna said:
dont want to start something here, but there seems to be a mis understanding of what a true series electrical circuit is.

In a series circuit you hook plus to minus, plus to minus, and so on.

In a parallel circuit you hook pluses together and hook minuses together.
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The only reason I avoided your advice on the multimeter was because I didn't currently have one on hand and didn't want to make the trip to the store if I could avoid it. I couldn't remember whether it was parallel or series, looks like I guessed wrong. I was banking on someone correcting me if I was wrong. I hate my EE classes, don't judge.

mrblaine said:
It's time to break out the voltmeter and find out what is going on. Those LED's should have a voltage tolerance of roughly 8.x to 14.x and power on fully in that range.

You need to check the voltage in your battery pack and compare it to the battery voltage in the vehicle at the connection points to start to find the problem.
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Voltage from both batteries is roughly the same 12.5V. Amperage is way different. Over 10A from the Jeep battery, 0.56A from the drill battery. What does this tell me/course of action? I hate electrical work and don't want to get this wrong and blow all the lights so sorry if these are all dumb questions.
 
Discussion starter · #26 ·
2jhanna said:
Take the switch out of the circuit. And run plus straight to the lights.
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I explained that I did that. I get the first light on full power, the second is a litter weaker and the third is barely lit. The rest are so weak they appear off or get no power. The reading of 10amps is from when the lights are connect straight to the battery.
 
Discussion starter · #28 ·
2jhanna said:
How are you reading amps? A LED should only be Mille or even micro amps.
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There's 48 LEDs total. The reading is in normal amps. From the drill battery they pulled 0.56 amps. When connect to the car battery they pulled over 10amps
 
#29 ·
rt4422 said:
There's 48 LEDs total. The reading is in normal amps. From the drill battery they pulled 0.56 amps. When connect to the car battery they pulled over 10amps
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Then you have a partial short to ground somewhere.

But still, how are you measuring amps, do you have a meter?

Also, how many "pods" are you hooking together?
 
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#31 ·
It would really help if you gave all the details. I would not run all 16 in a single "chain". I would split at least in 2, maybe even 3 or 4 chains.

What size wire are you using between the pods?

What is the current draw spec'd per pod?

Have you measured the voltage at the various points?

I find it hard to believe that a 12v drill battery is drives the entire circuit, and yet the switched circuit using the TJs battery is having a problem, unless there is a problem with the switch and/or power battery source.
 
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#32 ·
Okay, I was thinking about this. I bet he has the wires on the switch backwards. If I remember correctly, there is the ground, the positive and the load. If he swapped the positive and the load, it would probably kill his voltage because I bet the light in the switch has a diode in it. For some reason I think I've done this and the light on the switch wouldn't work and I was having difficulty with what I had wired up.

I would check that. Than I would just put the two positives together at the switch (the grounds should already be where they need. If you have the same problem, this eliminates the switch. and means the problem is in the wiring. If the problem goes way by touching the two wires together at the switch, I'd next check the ground. When you used the battery, did you use the batteries ground and all the original wiring or was that a bench test before installing.

If it was a bench test before installing than all it did was prove the lights are good and wired properly (which we already knew because it sounds like that's the only way they can go without modifying them). That leaves the wires and the switch.

Somebody mentioned a relay, but it doesn't look like you're using a relay in this circuit and it's probably not needed for LED lights. Somebody else mentioned wire size. I doubt that matters for LED because the current draw of LED lights is minimal, which is why a drill battery can drive them.

As far as voltage drop, since we've determined that the lights, while strung in series, are probably actually wired in parallel, I'm not sure if that'd tell you anything. I guess, using OHM's law, you might be able to do some paper trouble shooting, but I don't think you'd have much luck finding root cause.

Spent 2 years going to school 40hrs a week to learn how to trouble shoot electronics. In the end, the quickest way was always start eliminating things. Once I was actually on the job, we very rarely used o-scopes, meters, sig gens, ect.
 
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#33 ·
Post #17

2jhanna said:
I suggested a voltage check much earlier. My guess would be a mis wired switch. I bet the light inside the switch is in series with the load, causing a voltage drop.
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Post #25

2jhanna said:
Take the switch out of the circuit. And run plus straight to the lights.
Click to expand...
Post #26

rt4422 said:
I explained that I did that. I get the first light on full power, the second is a litter weaker and the third is barely lit. The rest are so weak they appear off or get no power. The reading of 10amps is from when the lights are connect straight to the battery.
Click to expand...
 
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#34 ·
i guess I get an F for reading comprehension. I blame too much food.

I went back and read everything, far more closer and agree, he's got a short to ground somewhere. The reason is the Battery shouldn't be able to power the lights because the ground (a better term is common) isn't common to the vehicle. Unless he's taking a wire from the common of the battery to the common of the vehicle. I wouldn't do this, FYI, for some reason, the term "Floating Ground" comes to mind.

True ground, if I remember correctly, only happens in a house where they actually run a rod into a ground and that is your common for the entire house. On other things, it's considered a common because there should be very little to no voltage from one point of common and another. Voltage is defined, if I remember correctly, as a difference in potential. Voltage is common in a parallel circuit, and Current changes, so you have Current drop as you go from one item in the ladder to the next. If it were Series, you'd voltage drop from one item in the string to the next. Somebody with more current knowledge can help me.

If it's lighting them, then, if I remember correctly, the voltage is there (which it should be, in a parallel circuit) but they're dim, then they don't have enough current to light them bright enough (going off 20 year old knowledge on this). That's why they get dimmer through the circuit, each rung in the ladder robs a little more current.

Since They do that when hooked up to vehicle power, something is stealing the current and running it to common. When you hook it up the battery, you still have the short but since your common isn't common to each other, that protects it from the current rob and lights all of them.

I could be way off on that. Too much food and now a few beers. I would check every connection. I would also start unplugging each pod. The error could be a bad pod.
 
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#35 ·
2jhanna said:
dont want to start something here, but there seems to be a mis understanding of what a true series electrical circuit is.

In a series circuit you hook plus to minus, plus to minus, and so on.

In a parallel circuit you hook pluses together and hook minuses together.
Click to expand...
Believe me I thought about this when I drove away for dinner and wished I kept my yap shut.
 
#36 ·
mrblaine said:
See, now here we go. Christmas lights used to be wired in series and the string would quit working when one burned out. You would have to rob a known good from a lit up string and replace each bulb in the dead string one by one until you found the bad one and the string lit up again. What was really fun was when two burned out at once. :rofl:
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Only an old fart would know and have experienced this... :laugh:
 
#37 ·
Knuckelhead said:
Only an old fart would know and have experienced this... :laugh:
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You don't have to be that old to have parents that thought the best way to keep kids busy on Thanksgiving day after turkey was to drag out old strings of lights and a box full of bulbs.

My pop doesn't even own a computer and the last time I visited, he was still playing 45's and occasionally a 78, it's like visiting an antique store sometimes.
 
#38 ·
mrblaine said:
You don't have to be that old to have parents that thought the best way to keep kids busy on Thanksgiving day after turkey was to drag out old strings of lights and a box full of bulbs.

My pop doesn't even own a computer and the last time I visited, he was still playing 45's and occasionally a 78, it's like visiting an antique store sometimes.
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My Dad started using a computer when his Dad (95 years old) started communicating with me while I was traveling the world in the 1980's.

He, my Dad and I are are Finnish and enjoyed many conversations while I traveled to many places. The one thing that stuck in my mind was my Grandpa stating that I have Sisu : http://en.wikipedia.org/wiki/Sisu

The best memory of Arvo (Grand Pa) was him chucking when I reminded him of my memories while I was growing up. Dad is still alive at 86 years old and I do enjoy his presence.

He was always trying to get me to go the collage. I told him that I wasn't a book smart, hands on dumb kind of guy.

He finally agreed after years of making my place working on MIL aircraft and weapon systems.
Then I went on to GPS satellite, AFSOC and a few other programs.

Now I'm retired and IDGAF...
 
Discussion starter · #39 ·
Well I appreciate all the feedback... I eventually gave up because I needed these done by tomorrow. Im just keeping the drill battery in the cab for the weekend and hooking them up at night. Ratchet, yes, but it gets the job done.

Trons said:
Voltage is common in a parallel circuit, and Current changes, so you have Current drop as you go from one item in the ladder to the next. If it were Series, you'd voltage drop from one item in the string to the next. ............ I would also start unplugging each pod. The error could be a bad pod.
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Correct, parallel carry the same voltage, series carries the same current. But the current was HIGHER for the TJ battery. I dont believe its a bad pod if they all work when hooked up to the drill battery...
 
#40 ·
Can you post a drawing of where and how the multimeter is when you measure this 10amp current draw.

Also, if you drill battery drives the lights while in the cab, all is good "downstream" ( toward the light pods) of that. The problem is "upstream" (toward to vehicle battery) of where the drill battery is installed.

Also, when the drill battery is in place, are you using the switch?
 
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Trons
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