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Nope...not for your fuel line. For little accessories that need to be removed or disconnected from time to time, but still require just a little DC juice . . . like my new mirror-mounted LEDs. (See my "MUTH "like" mirrors . . . on the cheap. Part II" thread.)

There are about a million options when it come to quick-disconnects for wiring, and I think I've just about tried them all. So I was staring at these wires and pontificating which route to go, when I looked over and saw my modular plug crimping tool. Four mod plugs and about 2 minutes later, and I was done. Below are the pics. I think this is really cool. Glad I thought of it. :D

TMI: These are RJ11 mod plugs for flat satin phone cable. Each plug has 4 conductors, so I split the wire and used the outside pair. This helps prevent the connections from shorting.










Phone guys RULE!!! :cool:
 

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Good idea Joe! For low draw apps like an LED array - those'd do fine in a protected environment. With the grease and what you're doing there - they should do fine - likely for quite some time.

I'm into 'Anderson PowerPoles'. I started using Molex type Nylon connectors back when (it's what was easily obtained at the local Shaque de Radio). But for most of what I do - ham type stuff - they've prooved to be seriously inadequate on many levels.

Power Poles look like this:

More info here: http://www.andersonpower.com/products/pp/pp.html and user supplied stuff here: http://home.comcast.net/~buck0/app.htm

They come in sizes rated from 15A to 180A, single and multiple connductors. They'd be serious over-kill (amperage wise) for what Joe's doing there. But radios, driving lights, other farkles with any kind of load or devices that are frequently discoed and reconnected - PPs are way more desireable.

I'd also suggest *not* using RJ type connectors for anything that draws more power than an LED array! Those itty bitty conductors won't take much power at all. Suggested limit is 0.577 amp for power transmission on 24 gauge wire.
http://www.powerstream.com/Wire_Size.htm

PPs also perform better in use than Nylon 'Molex' type connectors. Special over time and frequent connect/disconnect cycles.

Problems with Molex type are the more connect/disconnect cycles they go through, the poorer the connection gets (usable cycles counted in the hundreds). The female 'cylinder' expands each time, resulting in an air gap. Poorer connection, corrosion opportunity and creates a space for environmental contamination that makes it all worse over time and use.

Power Poles are rated for multiple thousands of connect/disconnect cycles. Self cleaning contacts are reported by some to decrease joint resistance with use! (not sure I quite buy into that, but it's possible). Not only rated for higher current, but they provide a much more robust physical package. Vibration and other mechanical mechanicals are better withstood, special over time.

Like many things in life, each to their own - use what you're comfortable with. Just be sure whatever you use is rated to support what you're doing.
 

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Discussion Starter #4
Thanks for the detailed response Tate. I'm going to get me some Power Poles, they look great! :thumb:
 

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33 years in telecommunications and I never thought of that!!! If your mirrors don't work call Ma Bell.....Neat use of a RJ
 

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Joe is a telephone man and necessity is the mother of invention. Just be aware that telephone wire and and the cheap plastic telephone connectors are not designed for automotive outdoor environments (heat, cold, wet oil, & gas) applications. I know I might be stepping on someones toes because Joe does have a masters degree in farkle installation.

I work for a company that manufacturers wire & cable. I would not suggest using cable that is not Underwriters Lab (UL) approved for the particular application for safety concerns and liability issues. I would have thought that 24 gauge or smaller wire (telephone wire) would not be big enough able to carry the line current necessary to operate a power applications like a turn signals lights on a motorcycle. Turn signal lights and LEDs in particular are a short term intermittent low voltage application but short circuits and sparks can be a safety concern particularly around gas pumps. Temperature & weather play a role in operation, longevity, and durability.

Telephone wire is made for a very light signal and very low power indoors. You might find the turn signals are brighter if you use the proper wire that is designed for this application. We do not make automotive wire. I am sure Underwriters Lab would object from a safety point of view.
 

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I agree with you for the most part. However, RJ connectors are actually pretty high quality inspite of their low cost. HIGH volume! Certainly you are correct in that they are low voltage, low current connectors. Using them to drive the LEDs is a good application though, very low current, probably less than 25 milliamps.

I had a Valentine radar detector on the LT (now in my car), with the remote display and remote audio module, they are all connected with RJ11 connectors.

I am a machine/system design engineer with a large interconnection manufacturer, and work with the component design engineers on a daily basis, so hear much about connector design parameters, and what is good and bad. RJ type connectors are way up there in the good category, for low current/voltage applications. Very reliable, all gold plated contacts.
 

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I just wanted to add to the wire gauge thing. I am a design engineer for automotive electronics. At one point in the not too distant pass, GM required a minimum of 18 gauge wire, regardless of amperage, simply from the standpoint of mechanical strength. That being said, my latest project, a set of road-following HID headlamps, are hooked up to 20 gauge a wiring harness. I went back to the GM spec, and can no longer find that requirement. I assume the weight nazi's finally trumped the durability nazi's.

Still, the 18 gauge requirement was a long standing one and I think a good one that I stick with.
 

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Discussion Starter #11
Awesome thread!

Part of my definition of "fulfillment" is when I'm able to gather the collective engineers at large and get them discussing one of my mods.
Thank you gentlemen! I am truly honored, and . . . humbled.


If I may add just a few "real world" notes, hints, allegations, and things left unsaid...

First of all, the wiring you see in the pics is 24 gauge. It came with the product. Had it been larger wire (or the current demand higher), I probably would not have used the RJ11 plugs. The wiring to your house supplying you with analog phone service (aka 'POTS' lines) supports 48V / 25mA all day long. Most modern inside cabling is 24ga twisted pair (CAT3 - CAT5e). Some of it is even braided copper fabric.

I also install a lot of Nortel Networks equipment. (Yes, I am trained and certified by NN.) Some of their digital products require the use of a Supplemental Auxiliary Power Supply (aka a "SAPS"). A Nortel SAPS is basically just a glorified AC "wall wart" that supplies 24V 0.25A. A 1/4 of an amp! Not just a few milliamp here. And guess what wiring supports this current? Yessir . . . 24gauge twisted pair into an RJxx plug.

So, can these RJ11s support a few LEDs (thus < 25mA)? I'm guessing so. And with the use of dielectric grease...I'm betting that the environment won't affect the performance of the connection either.

Thanks for your time and thoughts. I mean to belittle no one, just trying to contribute.
 

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All looks good to me Joe. Good idea and good discussion.

24ga wire's max current rate of .577A is well within the .25A draw your Nortel guys are using. I'd be quite surprised if any data farkle (radar detector, radios remote heads, GPS units) ran more than .25A as well.

One thing not mentioned here (kinda surprised), and what may well put anyone with any concern at ease, is to install a .5A fuse on any circuit with 24ga wire. That should help the UL testers be more comfortable. :up:

Something like what's offered here:
http://www.action-electronics.com/fuspico.htm

Be trivial to put a .5A fast blow pico-fuse on each line where it transistions from the stock wire harness to the 24ga (or even use a wire ga equel to the stock to lead to a more convienient fuse location). Use the .5A fues's axial lead to make the actual connection to the stock sized wires, put the 24ga on the other end. Does make changing fuses out a bit of a hassle, but you'll know your 'add ons' aren't going to create a problem for you. And even if the pico-fuse blows for some reason, you'll still have your stock signals. Not a trip stopper. (I'd bet your Nortel gear and the Valentine remote head already have such fuses on tehir RJ11 circuits. I know Motorolla and Kenwood tranceivers with remote heads do.)
 

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Just checked the 12V cigarette lighter adapter for my V1, and it has an 0.1A fuse in the tip.
 

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Zotter said:
(I'd bet your Nortel gear and the Valentine remote head already have such fuses on tehir RJ11 circuits. I know Motorolla and Kenwood tranceivers with remote heads do.)
Yep, either the cigarette lighter adapter or the remote power connector for the Valentine are fused. The Cig lighter adapter has the fuse in it, the remote power adapter has an inline fuse in it's power lead.
 

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Ken, Dave - I think you're both confirming that the device's power input is fused - and what I'd expect. An unfused power lead has no place on anything - well, only if you expect to call it 'right', that is.

What I'm expecting to find, though (and maybe what Dave said - inline, remote power fuse), is if someone opened up their device - say a V1 with a remote head - and looked at the connection to the remote head, there'd be another, lower rated fuse just for that remote connection. Likely real close to the RJ11 socket - maybe even have one in the remote head too. Often a pico-fuse is used, looks like a little, green grain of rice on the circuit board itself.

Of course, I don't expect anyone to go open up their farkle to look. Just commenting (and maybe suggesting?) that the idea of putting an extra, appropriately rated fuse to protect extender or remote head connector cords (like Joe's 24ga extensions to his LED mirror signals) isn't all that un-common. Idea is if the extender cord got pinched, crushed or damaged causing a short, instead of trashing the V1, it's remote head or causing a fire at a filling station, the pico-fuse would blow. BUT, since the main power fuse (the one in the cig plug, for example) wouldn't blow, the main unit itself would likely continue functioning. Repair/replace the extension cord, replace the fuse on the PCB and the remote would again function too.

Yea, I'm a fan of fuses - the more the better. Helps to isolate damage - making diagnostics and repair easier as well foster a better understanding of where your power is going and how it's being used. I've seen enough fire damaged LT body parts to last me already. But they do support the junk parts business!
 
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