Electronic Flasher Circuit

[SteveV]

Let's take a look at what you've got. From the pictures of you'r machine, there were 4 conventional addon lights in the rear if I recall. If the machine is going to spend much time in traffic, there's a strobe light system manufactured by Whelen Engineering that has the power supplies and strobe bulbs that the PD and Hwy Dept.'s use on their stuff./w3tcompact/icons/cool.gif Next assessment should be the wattage of the bulbs- add em up./w3tcompact/icons/shocked.gif Got anything of the front? Next consideration should be how long a service life is expected. A mechanical relay(s) can be had for 4 or 5 bucks (Potter Brumfield SPDT) with contact ratings of 15 amps or so. Two of these relays can be wired for alternating flash or purchased as a package as a headlight flasher. This will be fine unless you start logging 60 hr weeks on them. Then I'd use a public safety grade electronic headlight flasher (designed for switching current) and let the silicon do the work for a longer service life. Desipte how cool the combined turn signal functions are, I'd use a independent fused circuit and leave the stock turn signals alone. That way the first tree branch in the wrong place won't take out some obscure factory component when you haven't got time to mess with it! /w3tcompact/icons/hmm.gif Second choice would be to take a signaling current only (like less than 250 ma) from the directional circuit and use it for an input to my current handling circuit (read relay coil only). Worst case with the independent circuits would be both were trying to power the light at the same time and it would stay on continuously but would do no harm, both circuit are powered with the same source./w3tcompact/icons/smile.gif SteveV

 

[AndyR]

Sounds like a DPDT relay (double pole, double throw) could do what you are asking. You would wire up one side for the hazard flashers, but the other side would be wired up "opposite" for the turn signal. Think of it with the turn signal being perfectly out of phase with the hazard signal - so that if both are present the light stays on. /w3tcompact/icons/hmm.gif confusing - oh yeah./w3tcompact/icons/hmm.gif I'll try to diagram it tonight when I am back at home.

 

[MChalkley]

jfakerj - There's no way to tell if it's just a "tractor thing" or not, because there's no warning flashers at all, just turn signals. It might be a "euro" thing, though. So, since I'm adding flashers, I can (hopefully) make them work any way I like.

 

[MChalkley]

SteveV - If I have the flashers & turn signals working the way I want them to, I won't be using the work lights (the bright white ones along the canopy, of which there are 4 in the back and two up front) when I'm on the road. I will be using the "road lights", which turns on the two "headlights" on the front on either side of the cab, just above the hood, along with yellow marker lights on the front and red marker lights on the rear.

My 4" round LED lights have a bright and a dim connection. One of the beauties of LED lights is low current draw. The 4" round ones draw .2 amps in dim mode and .44 amps in high mode, which is less than the dimmest incandescent on the tractor and is essentially "noise level", in the quantities I'm using.

The rear red ones' dim mode will be connected to the EF-5's marker light circuit. The amber ones on the front and both sides will also be connected in dim mode to the EF-5's marker light circuit. The red ones' bright mode will be connected to the brake light circuit, obviously. The 4 amber lights on the left side (1 in front, 2 on the left side, 1 on rear) will be connected to the left turn signal circuit in bright mode, the 4 right side ones connected to the right turn signal circuit, and all 8 connected to the hazard warning circuit, which I will be adding.

I'd rather leave the factory turn signal circuit alone, too. But, if I just add a hazard flasher circuit, when it's on, it will interfere with the turn signals. Better, perhaps, to right some sort of switch/relay into the output side of the existing turn signal to accomplish the desired effect. The flasher on the EarthForce machines is a heavy duty Hella 20-amp one, so I'm not worried about overloading it.

 

[MChalkley]

AndyR - Thanks for your help.

It just occurred to me that I might be making this a little more difficult than it needs to be. I went out and snatched the Hella flasher out of the fuse box and guess what? It's got 6 contacts on it, but only 3 of them are being used. I did a search of the Internet, though, and I can't find any information on it, using the markings on it. Does anybody have access to Hella literature? Here's a list of the markings on it: "Hella", "TB83", "BLINKGEBER", "Made in Germany", "4DN 006 208-00", "12V21W2+1+1(8)P", and "71458". It's also got a contact diagram on it, listing contacts numbered 31, C2, C3, 49a, C, and 49. C3, 49, and 49a are being used. Any ideas, anyone?

 

[dummy]

If you don't have the whole diagram, try www.hellausa.com . They have relays listed under automobile electronics, but I can't get into their site from here.

 

[MChalkley]

Thanks, but I tried www.hella.com and www.hellausa.com. They do list the product lines in general, but no products in specific and no tech info.

 

[SteveV]

This would be a good place for me to bow out of this discussion, since most heavy equipment has prepackaged electronics these days and not only do you need to find the necessary connection point with available capacity, but there also needs to be a way to physically attach your connection to theirs. I missed the word "LED" in a previous post,/w3tcompact/icons/hmm.gif most of my electrical current related running off at the keyboard was unnecessary. Sounds like the 'What cha got' and 'what you want' is getting close. /w3tcompact/icons/smile.gifSteveV

 

[AndyR]

Mark, I have a few ideas but each one varies with what the circuit looks like. I am wondering if your flasher module is switching the ground leg of the lamps involved. If this was the case, a general purpose flasher module would be activated when either the flashers or turns signals are operated. For this case, the bulk of the switching is done by your switches (as opposed to the relay). If you have an ohmeter you could check this (hint hint) and we could go from there.

I like your LED lights. [we now jump to the kinda-near future. Dateline 2005. Kubota announces LED lightbars/w3tcompact/icons/cool.gif along top of loader buckets and around back of the ROPS. Tractor owners cheer!/w3tcompact/icons/grin.gif]

 

[MChalkley]

Andy - In checking the wiring diagram, the terminals used by the flasher are Ground, 12v(+) In, and 12v Out. The circuit works by a single 3-position switch (On-Off-On) connecting the 12v leg of one side's turn signal lights to the 12v Out terminal of the flasher. So it's the Positive side that's switched.

I was mistaken as to which terminals on the flasher are being used. They are 31, 49a, 49b.

FWIW, the DIN standard for the terminals listed on the flasher describes them this way. Under a heading called "Turn-signal flashers (pulse generators)" it lists:

31 - Battery negative terminal, or ground, direct
49 - Turn-signal flasher input
49a - Turn-signal flasher output

I understand those three, and they're the three in use. It also lists two more that my flasher doesn't have:

49b - Output, second circuit
49c - Output, third circuit

But here's the description for the other three, not in use, which I don't understand. They're under a separate group heading called "Directional signals (turn signal flashers)".

C - Indicator lamp 1
C2 - Indicator lamp 2
C3 - Indicator lamp 3 (e.g. when towing two trailers)

It seems weird that my flasher combines numbering schemes from two different sections of the DIN standard, but just as weird that there's two different sections for what seem to be the same thing in the first place. Interestingly, though, there is no section in the DIN standard for warning, or hazard, lights. Maybe the second section really means warning lights? If so, why call it almost the same thing as the first section? Thanks for your help!