Login | Register

Previous in Forum: Problems with Surveillance Cameras   Next in Forum: KVA
Close

Comments Format:






Close

Subscribe to Discussion:

CR4 allows you to "subscribe" to a discussion
so that you can be notified of new comments to
the discussion via email.

Close

Rating Vote:







55 comments
Guru

Join Date: Sep 2007
Posts: 1963
Good Answers: 7

LED Indicator Strips and Resistors

05/05/2008 8:57 AM

I have replaced my normal bulbs (all 4) with LED indicator strips. All the flashing problems I see mentioned relate to the LED flashing too fast and to correct this you introduce a load resistor which would mimic the bulbs and correct the problem.

My problem is that they do not flash at all, they come on and stay on, so do I have the same problem and will a resistor work?

Secondly if the bulbs are only 5Watt each, how come the correction load resistor is 50Watt as stated by some suppliers that provide these as a solution to LED indicators?

Many thanks,

Case491

Send to a friend Digg this Add to del.icio.us
Pathfinder Tags: flashing indicator LED
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

Comments rated to be Good Answers:

These comments received enough positive ratings to make them "good answers".

Comments rated to be "almost" Good Answers:

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, rate them!
2
Guru
United Kingdom - Member - New Member Engineering Fields - Instrumentation Engineering - New Member Fans of Old Computers - Vector 1 - New Member

Join Date: Jul 2006
Location: Dunstable, England
Posts: 2476
Good Answers: 33
#1

Re: LED Indicator Strips and Resistors

05/05/2008 2:23 PM

Are the flasher units still based on the old design of a bimetallic strip?

If so then they need the current flow of the filament bulbs to heat them up and give the correct flash rate, which is due to the filament current.

In a normal filament bulb car if a bulb blows the flasher unit will tell you by showing a dramatic change in the flash rate, or even not flashing at all.

As the filament bulbs take about 50 watts I would guess this is the size of resistor you will need to switch the flasher unit on and off...

Seems far more realistic to replace the flasher unit with an electronic version...

John.

__________________
I failed my DNA test - it was my parents' fault.
Good Answer (Score 2)
Guru

Join Date: Sep 2007
Posts: 1963
Good Answers: 7
#2
In reply to #1

Re: LED Indicator Strips and Resistors

05/05/2008 2:43 PM

Yes the total load is 21Watt doubled up so comes to 42 Watt. I wrongly thought they were 5Watt but only the side lights are 5Watt.

With regards to the flasher unit replacement for a new electronic one, the thing against it is that often on modern vehicles this flasher unit comes with built in electronics for feedback to the ECU or EMU. These feedbacks range from bulb breakage or missing to time indicator on. In the case of a motorcycle it also includes lean angle and yards moved till switched off automatically. These features mean that replacement is hard and if possible very expensive. Cheaper to load the system up with a load resistor.

Thanks you made me look again and find my answer. The resistor will help with my problems.

Guru
United Kingdom - Member - New Member Engineering Fields - Instrumentation Engineering - New Member Fans of Old Computers - Vector 1 - New Member

Join Date: Jul 2006
Location: Dunstable, England
Posts: 2476
Good Answers: 33
#3
In reply to #2

Re: LED Indicator Strips and Resistors

05/05/2008 2:54 PM

Oh I didn't know they had extras on them these days...

I seem to remember that most cars indicator bulbs were about 21 to 23 watts which together with the side indicators gives about 50 watts loading.

I suppose if the power is there and its not going to make a major problem using it then as you say it will be easier to just waste the power into a resistor or possibly into heated gloves???

John

__________________
I failed my DNA test - it was my parents' fault.
Score 1 for Good Answer
Guru

Join Date: Sep 2007
Posts: 1963
Good Answers: 7
#4
In reply to #3

Re: LED Indicator Strips and Resistors

05/05/2008 3:15 PM

Hmmmmm, now there is an idea!

What is the wattage of those heated grips? We have to look that up and see if I can somehow divert that loss. Thanks again for another good idea.

Guru

Join Date: Sep 2007
Posts: 1963
Good Answers: 7
#5
In reply to #3

Re: LED Indicator Strips and Resistors

05/05/2008 3:17 PM

http://www.4-motorcycles.co.uk/acatalog/Heated_Grips.html


That looks to be exactly right to me. Maybe need to also have them on me toes though to get the right amount when just in the "on" position

Might just give this a go some time before next winter.

Guru
United States - US - Statue of Liberty - New Member

Join Date: Nov 2007
Location: Crystal River, FL
Posts: 3031
Good Answers: 9
#8
In reply to #5

Re: LED Indicator Strips and Resistors

05/06/2008 11:29 AM

Hey, not only is this 'thinking outside the box', this is saying 'there's a box?'! Love it!

Case, recommend you well-document the wiring diagram once you get it figured out. Looks to me like it will be just complicated enough to never be able to recall 'where that wire goes' in about 2 year's time...

__________________
Don't worry about what people think - they don't do it very often...
Guru
Popular Science - Weaponology - New Member Safety - ESD - New Member

Join Date: Sep 2006
Location: Near Frankfurt am Main, Germany. 50.390866N, 8.884827E
Posts: 4886
Good Answers: 16
#6

Re: LED Indicator Strips and Resistors

05/06/2008 3:13 AM

Yes it will.

The reason they are staying on is that the flasher unit that you have needs the current to operate correctly. No (or should I say -far less) current = no flash.

Or you need to design a flasher unit that works independent of the current taken, a simple 555 circuit should be able to do that for you.....

__________________
"A lie or untruth is halfway round the world before the truth has got its trousers on" Sir Winston Churchill
Guru

Join Date: Sep 2007
Posts: 1963
Good Answers: 7
#9
In reply to #6

Re: LED Indicator Strips and Resistors

05/06/2008 3:09 PM

555 circuit???? Sorry but that is just a little short of the real deal 666 circuit

Sorry but I have to decline as only the best is good enough for me and my hog

I have ordered the 50 watt resistors from e-bay late last nite and I am eagerly awaiting.

The heated handgrips will have to wait as I have decided that if you have heated handgrips, you need heated toes as well and where do you draw the line. Heated crotch pocket?

That would be nice but no thanks

Guru
United Kingdom - Member - New Member Engineering Fields - Instrumentation Engineering - New Member Fans of Old Computers - Vector 1 - New Member

Join Date: Jul 2006
Location: Dunstable, England
Posts: 2476
Good Answers: 33
#10
In reply to #9

Re: LED Indicator Strips and Resistors

05/06/2008 3:50 PM

Hmmmm that reminds me of a time 30 years ago, when I was riding home on my trusty motorbike in winter and I suddenly realised that certain parts of my anatomy were numb from the cold....

I stopped and for several minutes at the side of the road I was jumping up and down massaging myself to get some feeling back... Luckily nobody reported me

John

__________________
I failed my DNA test - it was my parents' fault.
Guru

Join Date: Sep 2007
Posts: 1963
Good Answers: 7
#11
In reply to #10

Re: LED Indicator Strips and Resistors

05/06/2008 3:59 PM

Where I live, they have a name for that

And you can get banged up for that too if unlucky

I remember riding my 1967 BSA Barracuda in the winter to work and I suddenly felt a cold trickle between the legs. Looked down to spot this frozen clump of ice that had settled in my crotch which was melting due to being "out of the wind" behind the tank. The water was ice cold (duh) and trickling in through the seems of my supposedly all weather over trousers.

Crotch warmer seems very attractive in situations like that.

Off Topic (Score 5)
Guru
United Kingdom - Member - New Member Engineering Fields - Instrumentation Engineering - New Member Fans of Old Computers - Vector 1 - New Member

Join Date: Jul 2006
Location: Dunstable, England
Posts: 2476
Good Answers: 33
#12
In reply to #11

Re: LED Indicator Strips and Resistors

05/07/2008 7:19 AM

Yes, last night I thought to myself whether anyone had designed and put on the market a heated 'cricket box' type of device for male motorcyclists!!

John

__________________
I failed my DNA test - it was my parents' fault.
Off Topic (Score 5)
Guru
United States - US - Statue of Liberty - New Member

Join Date: Nov 2007
Location: Crystal River, FL
Posts: 3031
Good Answers: 9
#13
In reply to #12

Re: LED Indicator Strips and Resistors

05/07/2008 8:07 AM

Pardon the intrusion, but I seem to sense a marketing niche here. OBTW, don't forget the lady riders...

__________________
Don't worry about what people think - they don't do it very often...
Off Topic (Score 5)
Guru
Popular Science - Weaponology - New Member Safety - ESD - New Member

Join Date: Sep 2006
Location: Near Frankfurt am Main, Germany. 50.390866N, 8.884827E
Posts: 4886
Good Answers: 16
#14
In reply to #13

Re: LED Indicator Strips and Resistors

05/07/2008 8:33 AM

You mean a "Hot Box" accessory?

__________________
"A lie or untruth is halfway round the world before the truth has got its trousers on" Sir Winston Churchill
Off Topic (Score 5)
Guru
United States - US - Statue of Liberty - New Member

Join Date: Nov 2007
Location: Crystal River, FL
Posts: 3031
Good Answers: 9
#15
In reply to #14

Re: LED Indicator Strips and Resistors

05/07/2008 11:26 AM

Errr...yes, I guess so - as long as it's naught to do with railroading, I guess that'd be OK...

__________________
Don't worry about what people think - they don't do it very often...
Off Topic (Score 5)
Guru
United Kingdom - Member - New Member Engineering Fields - Instrumentation Engineering - New Member Fans of Old Computers - Vector 1 - New Member

Join Date: Jul 2006
Location: Dunstable, England
Posts: 2476
Good Answers: 33
#16
In reply to #15

Re: LED Indicator Strips and Resistors

05/07/2008 11:34 AM

Errrrmmmm maybe I'm a bit naive but what is 'railroading' as used in your post??

Or don't I want to know?

__________________
I failed my DNA test - it was my parents' fault.
Off Topic (Score 5)
Guru
United States - US - Statue of Liberty - New Member

Join Date: Nov 2007
Location: Crystal River, FL
Posts: 3031
Good Answers: 9
#17
In reply to #16

Re: LED Indicator Strips and Resistors

05/07/2008 12:43 PM

Whether you want to know or not is none of my affair. What I was referring to was that when the brakes used to overheat on rail car wheel trucks, it was called a 'hot box' because the braking mechanism was enclosed partially in a box-like structure. This was undesirable because it could burn a boxcar to the ground, or cause brushfires along the right-of-way. In the sense that Andy G. was using the term, it would not (necessarily) be undesirable. (I hope that was how he was using it, anyway!)

__________________
Don't worry about what people think - they don't do it very often...
Off Topic (Score 5)
Guru
Popular Science - Weaponology - New Member Safety - ESD - New Member

Join Date: Sep 2006
Location: Near Frankfurt am Main, Germany. 50.390866N, 8.884827E
Posts: 4886
Good Answers: 16
#18
In reply to #17

Re: LED Indicator Strips and Resistors

05/07/2008 2:38 PM

Actually a Railroad "Hot Box" is referring to the axles and in particular, the bearing.

All over the world are fitted so called "Hot Box" detectors to warn the signalmen when to halt a train.

Its still common practise, I even know someone who installs them!! They can tell the signalman even which car/wheel has the problem at the full speed of the train.....

__________________
"A lie or untruth is halfway round the world before the truth has got its trousers on" Sir Winston Churchill
Off Topic (Score 5)
Guru
United States - US - Statue of Liberty - New Member

Join Date: Nov 2007
Location: Crystal River, FL
Posts: 3031
Good Answers: 9
#23
In reply to #18

Re: LED Indicator Strips and Resistors

05/07/2008 3:29 PM

Yeah, they're much more sophisticated these days. Used to be the train crew, brakeman usually, had to check them visually...

__________________
Don't worry about what people think - they don't do it very often...
Off Topic (Score 5)
Guru

Join Date: Sep 2007
Posts: 1963
Good Answers: 7
#24
In reply to #23

Re: LED Indicator Strips and Resistors

05/07/2008 3:31 PM

What you do, you touch them to see if it hurts?

Off Topic (Score 5)
Guru
United States - US - Statue of Liberty - New Member

Join Date: Nov 2007
Location: Crystal River, FL
Posts: 3031
Good Answers: 9
#27
In reply to #24

Re: LED Indicator Strips and Resistors

05/07/2008 3:44 PM

Only if you can't see them glowing red or giving off smoke...

__________________
Don't worry about what people think - they don't do it very often...
Off Topic (Score 5)
Guru

Join Date: Sep 2007
Posts: 1963
Good Answers: 7
#28
In reply to #27

Re: LED Indicator Strips and Resistors

05/07/2008 3:52 PM

The hot thing reminded me of this joke:

Stupid people should have to wear signs that just say, "I'm Stupid"

That way you wouldn't rely on them, would you? You wouldn't ask them anything. It would be like, "Excuse me...oops, never mind. I didn't see your sign." ...

It's like before my wife and I moved. Our house was full of boxes and there was a U-Haul truck in our driveway. My friend comes over and says, "Hey, you moving?" "Nope. We just pack our stuff up once or twice a week to see how many boxes it takes. Here's your sign."

A couple of months ago I went fishing with a buddy of mine, we pulled his boat into the dock, I lifted up this big 'ol stringer of bass and this idiot on the dock goes, "Hey, y'all catch all them fish?" "Nope - Talked 'em into giving up. Here's your sign."

I was watching one of those animal shows on the Discovery Channel. There was a guy inventing a shark bite suit. And there's only one way to test it. "all right Jimmy, you got that shark suit on, it looks good...They want you to jump into this pool of sharks, and you tell us if it hurts when they bite you."
"Well, all right, but hold my sign. I don't wanna lose it."

Last time I had a flat tire, I pulled my truck into one of those side-of-the-road gas stations. The attendant walks out, looks at my truck, looks at me, and I SWEAR he said, "Tire go flat?" I couldn't resist. I said, "Nope. I was driving around and those other three just swelled right up on me.
Here's your sign."

We were trying to sell our car about a year ago. A guy came over to the house and drove the car around for about 45 minutes. We get back to the house, he gets out of the car, reaches down and grabs the exhaust pipe, then goes, "Darn that's hot!" See?
If he'd been wearing his sign, I could have stopped him.

I learned to drive an 18 wheeler in my days of adventure. Wouldn't ya know I misjudged the height of a bridge. The truck got stuck and I couldn't get it out no matter how I tried. I radioed in for help and eventually a local cop shows up to take the report. He went through his basic questioning. No problem. I thought for sure he was clear of needing a sign... until he says "So..is your truck stuck?" I couldn't help myself! I looked at him, looked back at the rig, then back to him and said, "No I'm delivering a bridge ...Here's your sign!"

Sure you must have heard this one before? Sure made me laugh.....twice.

Off Topic (Score 5)
Guru
United States - US - Statue of Liberty - New Member

Join Date: Nov 2007
Location: Crystal River, FL
Posts: 3031
Good Answers: 9
#34
In reply to #28

Re: LED Indicator Strips and Resistors

05/07/2008 4:35 PM

Gives a whole new meaning to an otherwise inane question - what's your sign?

ROFLMSAO!!! Yes, I'd heard some of those before, but not strung together like that! Sure would save time and breath upon occasion though, wouldn't it?!?

__________________
Don't worry about what people think - they don't do it very often...
Off Topic (Score 5)
Power-User

Join Date: Sep 2007
Posts: 171
Good Answers: 7
#7

Re: LED Indicator Strips and Resistors

05/06/2008 6:32 AM

Incandescent bulbs have a hot/cold resistance ratio of about 10/1. This means that that when they are operated from a voltage source, the cold current is about 10 times the hot current. The flasher designers know this and design the flasher to flash at the desired rate under average current draw. Your LED lamps exhibit constant current drain and provide a different loading profile to the flasher.

Guru

Join Date: Sep 2007
Posts: 1963
Good Answers: 7
#19

Re: Resistors don't seem to work...HELP

05/07/2008 2:55 PM

Ok bought the little gold beauties but they do not work....at all.

Yet when I introduce even the one normal bulb (21Watt), it blinks fine.

Anyone any ideas here?

Guru
United Kingdom - Member - New Member Engineering Fields - Instrumentation Engineering - New Member Fans of Old Computers - Vector 1 - New Member

Join Date: Jul 2006
Location: Dunstable, England
Posts: 2476
Good Answers: 33
#20
In reply to #19

Re: Resistors don't seem to work...HELP

05/07/2008 3:05 PM

'gold beauties'... are these the power resistors? are they supposed to dissipate 50 watts at whatever the voltage is on a Harley (12volts? so therefore about 3 ohms each resistor).

But the indicators work with a 21 watt bulb?

John.

__________________
I failed my DNA test - it was my parents' fault.
Guru

Join Date: Sep 2007
Posts: 1963
Good Answers: 7
#22
In reply to #20

Re: Resistors don't seem to work...HELP

05/07/2008 3:27 PM

Ok , I had not measured the ohms yet but they are 9.6 ohm each????

This would make for 115 Watt which clearly would be too high. Why would somebody sell these for this purpose?? I am even more confused and perplexed now.

The 2 led indicators work correctly when I introduce 1 of 21Watt normal bulb in addition to the 2 leds.

This makes me question a normally used concept in DC motor braking with power resistors. These big gold coloured resistors are always rated in Watts but that has to be dependend on Voltage or not? DC motors voltage varies anyway so how does this work?

Sorry I stray off the important issue here but still........

Guru
United Kingdom - Member - New Member Engineering Fields - Instrumentation Engineering - New Member Fans of Old Computers - Vector 1 - New Member

Join Date: Jul 2006
Location: Dunstable, England
Posts: 2476
Good Answers: 33
#25
In reply to #22

Re: Resistors don't seem to work...HELP

05/07/2008 3:39 PM

9.6 ohms they're no good, you want at least 5 ohms or less...

The 21 watt bulb is taking almost 2 amps and the resistors are only taking just over one amp = 14 watts...

If you need to dissipate 48 watts you need a resistance of 3 ohms...

You've been sold the wrong ones by the sound of it...

John.

__________________
I failed my DNA test - it was my parents' fault.
Guru

Join Date: Sep 2007
Posts: 1963
Good Answers: 7
#26
In reply to #25

Re: Resistors don't seem to work...HELP

05/07/2008 3:43 PM

I think you are right. I will take it up with this e-bay dealer right now. Good thing is he has reasonable feedback so he might want to keep that.

Guru

Join Date: Sep 2007
Posts: 1963
Good Answers: 7
#29
In reply to #25

Re: Resistors don't seem to work...HELP

05/07/2008 3:54 PM

I is still confused about this load business.

The bulb heats up and its resistance changes or not?

If so , how is a steady load resistor ever going to fool the blinker unit?

Guru
Popular Science - Weaponology - New Member Safety - ESD - New Member

Join Date: Sep 2006
Location: Near Frankfurt am Main, Germany. 50.390866N, 8.884827E
Posts: 4886
Good Answers: 16
#31
In reply to #29

Re: Resistors don't seem to work...HELP

05/07/2008 4:02 PM

Do not worry, two in parallel should do it for you!

__________________
"A lie or untruth is halfway round the world before the truth has got its trousers on" Sir Winston Churchill
Guru
Popular Science - Weaponology - New Member Safety - ESD - New Member

Join Date: Sep 2006
Location: Near Frankfurt am Main, Germany. 50.390866N, 8.884827E
Posts: 4886
Good Answers: 16
#30
In reply to #22

Re: Resistors don't seem to work...HELP

05/07/2008 4:00 PM

Try using 2 resistors in parallel....

__________________
"A lie or untruth is halfway round the world before the truth has got its trousers on" Sir Winston Churchill
Guru

Join Date: Sep 2007
Posts: 1963
Good Answers: 7
#32
In reply to #30

Re: Resistors don't seem to work...HELP

05/07/2008 4:06 PM

Woahh, I must live in a parallel world already. I just saw your post double, as in parallel with itself.

I will try right now but don't see how it would work in this setup.