RJ12 cables.

Hornby use 3 wire, 6 contact RJ 12 plug and wire cables. To correct
the polarity each end is fitted with it's plug inverted. Does anyone
have any idea why a similar plug with full 6 wire connections produces
a fault? In my book redundant wiring should not pose any problems.
Reply to
Sailor
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Without knowing which pins are actually in use, from your description of 'inverted', I would suspect that the 3 active wires are actually going to unused pins at one end.
Consider the case where pins 1 to 3 are in use, and at the other end pin 1 will go to 3, 2 to 2 , and 3 to 1. Now if you invert all 6 wires then 1 will go to 6, etc, and no connection will be made!!
As I say without a fuller description of the pins in use, it might be the answer.
Regards Jeff
Reply to
Jeff
That is simple to answer -- alternating pins are used. Say 1,3 &5. As the distant plug is inverted it puts the sequence in the correct order in order to enter it into the next unit or combining socket. This is why I wonder at the fault situation.
Reply to
Sailor
Are you saying that only pins 1,3 & 5 are used at both ends??
If that is the case then my assumption is correct; if you reverse the wires to all 6 pins and keep the sequence in the same (but reversed) colour order then pin 1 would go to pin 6 (not used), 3 to 5 (wrong pin), and 5 to 2 (not used)!!!!
Regards Jeff
Reply to
Jeff
But if you can check the colours then you know the pins are in the correct sequence. Then you can check pin to pin connectivity and know your cabling is correct. Then you know you have misunderstood the connections. ;-)
Cheers, Simon
Reply to
simon
Indeed, but so far no one has actually posted the pin to pin sequence for each end!!
All that has been said is that the connections are 'inverted'; unfortunately this can mean different things.
If the colour sequence is kept the same at both ends but 'inverted' then pin 1 will go to pin 6 etc. with finally pin 6 going to pin 1.
Is that the same sequence as when only 3 wire are in use???
Regards Jef
Reply to
Jeff
There are 6 pins. The plugs are identical with a locating/locking tab which ensures correct entry. The departing plug (pin1 to the right) uses 1 red 3 green & 5 blue. At the other end the plug is inverted (this is RJ12 language). Regarding this plug in the same orientation as the departing one shows the same sequence. Each device whether Elite or Select has skts with the same orientation. This is the reason for the inversion. A similar but 6 wire cable is used to branch in the power booster unit (if used). The 3 wire unit is described by Hornby as a 4 wire unit -- my magnifying glass says otherwise!
I have emailed Hornby and await a reply.
Regards
Reply to
Sailor
It is the use if the word 'inverted' that is causing a problem (it is not RJ12 language, RJ12 cables normally come as straight through or cross-over).
You have explained which pins are in use at the 'departing' end, but missed the critical bit of which pins are used at the other end!!! Which pins do the red, green and blue wires go to at the far end in a 3 wire cable?
Your post says "Regarding this plug in the same orientation as the departing one shows the same sequence". By that do you mean that the red wire is on pin 1, green on 3 and blue on 5? If so in what way is this 'inverted', as it is wired pin to pin; ie straight-through!!
Regards Jeff
Reply to
Jeff
A straight through cable reverses the sequence such that pin 1 depart will arrive at pin6 of the other end ( which is also facing in the other direction from the departing plug. By rotating the distant plug through 180=B0 the wires are now set at red to 1! My catalogues for UK Aus & US refer to reversed or inverted for such an arrangement. Straight through does indeed reverse the sequence. Hornby uses parallel connectors for extension leads which also leaves you with a live plug exposed(very unprofessional). I have through cable joiners which could be used with a straight through cables provided that the other one was "reversed".
Regards
Reply to
Sailor
A straight through cable reverses the sequence such that pin 1 depart will arrive at pin6 of the other end ( which is also facing in the other direction from the departing plug. By rotating the distant plug through 180° the wires are now set at red to 1! My catalogues for UK Aus & US refer to reversed or inverted for such an arrangement. Straight through does indeed reverse the sequence. Hornby uses parallel connectors for extension leads which also leaves you with a live plug exposed(very unprofessional). I have through cable joiners which could be used with a straight through cables provided that the other one was "reversed".
Regards
============================== Curious, in computing terms - presume these come from there - there is crossover and straight through. Crossover was to swap send and receive so pin 2 went to 3 and 3 to 2. Straight through was as expect, 2 to 2 and 3 to 3.
Cheers, Simon
Reply to
simon
=3D=3D=3D=3D=3D=3D
I wonder if I have bored the crap out of people yet!
A straight through flat cable has two formats ( hence the confusion).
1. Each plug has it's locating tab uppermost and the cores run parallel. This has the effect of reversing the sequence at the receiving end.
2. The cores are not run parallel but crossed over enroute. This produces a receiving plug with the identical format to the sender.
The normal way to make up the second is not to mess with internal crossovers but to simply rotate the receiving plug axially through 180=B0 (the locater is now pointing down (not up like the sender). This is the Hornby cable format.
I had read the Hornby Forum posting and queried the data as I can see only 3 cores in use (red, green and blue).
My fastest remedy will be to carefully destroy two of my commercial straight through extention connectors and make it into a test unit to determine the configuration.
Why should I be fussed? The R8266 cable has disappeared from the online market place. My supplier in Toulouse will make up any configuration I desire - once I know what it is!
Reply to
Sailor
Surely the fastest way would be to use a test meter (or a psu and a light bulb) and determine exactly which pin connects to which in a working cable!!!
As I said in my previous posts what is missing is the pin to pin layout of the cable.
Regards Jeff
Reply to
Jeff
I wonder if I have bored the crap out of people yet!
A straight through flat cable has two formats ( hence the confusion).
1. Each plug has it's locating tab uppermost and the cores run parallel. This has the effect of reversing the sequence at the receiving end.
2. The cores are not run parallel but crossed over enroute. This produces a receiving plug with the identical format to the sender.
The normal way to make up the second is not to mess with internal crossovers but to simply rotate the receiving plug axially through 180° (the locater is now pointing down (not up like the sender). This is the Hornby cable format.
I had read the Hornby Forum posting and queried the data as I can see only 3 cores in use (red, green and blue).
My fastest remedy will be to carefully destroy two of my commercial straight through extention connectors and make it into a test unit to determine the configuration.
Why should I be fussed? The R8266 cable has disappeared from the online market place. My supplier in Toulouse will make up any configuration I desire - once I know what it is!
=================================================== Nope not bored cos intend to get cable myself. My goodness, you must have been in france too long, its very complicated the way you describe things ;-)
Can we start from .... If you look at the connectors end on next to each other and at the same orientation ....if was d connector then
|) |)
the pins are numbered in an identical sequence even if one is male and the other female. Could you describe if crossover or straight through from this ?
Cheers, Simon
Reply to
simon
In 'normal' speak a straight-through cable is wired pin 1 to pin1, pin 2 to pin 2, etc.
A cross-over cable is wired so that it will function when plugged in a a certain application, and does not always mean that the pin numbering is just simply reversed, such as a null-modem cable where for example tx and Rx data pins are swapped, but others such as Ground are not.
The complication with RJ12 and the like are that connectors are available that allow flat cable to be used and still be wired 'straight-through' pin to pin. The attaching of the cable to the connector may be 'inverted' but the pin connections are not!!!
Reagrds Jeff
Reply to
Jeff
.
=3D=3D=3D=3D=3D=3D=3D
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D
OK! RJ12 plugs (free plugs which connect to flat or round cable ) are all male. Sockets are female and generally live in an equipment enclosure.
In this case (Hornby) they have used the lenz arrangement so that all equipment ( Elite, select and power boost module) uses identical sockets.
Now , if you have two RJ12 plugs and a length of flat wire and you number pins from left to right when looking into the plug from the free end and then repeat this at the other end (locating lugs being both upwards) then the pin1 of the left plug will appear at pin 6 of the right. This to me and US & French suppliers is called "through connected". Every conductor will have appeared on a different pin.
The way this is overcome is to rotate one plug axially thriugh 180=B0 thus the plug still faces away from the cable but the locking tab is now downwards. The conducter leaving on No1 pin now arrives on No1 pin the other end. If you have an Elite unit there should be an R8266 with it (4 core) . The R8236 is 6 core for the R8239 power booster.
Now I have to butcher my through connectors because I neither have prods small enough or eyes good enough to fart about inside of an 8mm wide aperture containing 6 contacts 0.2 mm apart! I notice that the 8266 has reappeared on the Hornby site!
What is much easier is for someone to come up with an answer! It is so much cheaper on the open market 1=8025 compared with 5.5 GBP.
Reply to
Sailor
OK! RJ12 plugs (free plugs which connect to flat or round cable ) are all male. Sockets are female and generally live in an equipment enclosure.
In this case (Hornby) they have used the lenz arrangement so that all equipment ( Elite, select and power boost module) uses identical sockets.
Now , if you have two RJ12 plugs and a length of flat wire and you number pins from left to right when looking into the plug from the free end and then repeat this at the other end (locating lugs being both upwards) then the pin1 of the left plug will appear at pin 6 of the right. This to me and US & French suppliers is called "through connected". Every conductor will have appeared on a different pin.
The way this is overcome is to rotate one plug axially thriugh 180° thus the plug still faces away from the cable but the locking tab is now downwards. The conducter leaving on No1 pin now arrives on No1 pin the other end. If you have an Elite unit there should be an R8266 with it (4 core) . The R8236 is 6 core for the R8239 power booster.
Now I have to butcher my through connectors because I neither have prods small enough or eyes good enough to fart about inside of an 8mm wide aperture containing 6 contacts 0.2 mm apart! I notice that the 8266 has reappeared on the Hornby site!
What is much easier is for someone to come up with an answer! It is so much cheaper on the open market 1?25 compared with 5.5 GBP.
===============================================
Sorry, but this is a uk newsgoup so you must use the uk convention :-) Actually am suprised US is different as most of the PC/Comms stuff for computing comes from there .....
Anyway, checked spec on lenz site - manuals.
formatting link
Scroll down to the diagram. You can see its quite specific with 4 connected wires and straight through, not a crossover in sight (in uk description terms). Actually it seems US describes same as straight through !
Note the description for data wires :- "One must pay particular attention to the orientation of the A and B-lines. Exchanging these leads will result in no data communication"
Although it doesnt say it, you shouldnt cross ground and 12 volts for obvious reasons.
Cheers, Simon
Reply to
simon
...
=3D=3D=3D=3D=3D=3D=3D
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
Thanks for the Lenz data ;
they run from DIN to RJ12. Interestingly they show a 6 core with unused 1&6.
Now that I have managed to check my R8266 4 core flat cables I find that they are in fact 6 core R8236s (sold as 8266). The two that I have in use work fine ( with the exception that the handheld units seem to have direct speed control rather than the incremental acc & decc of the main unit. The new cable is identical to the Hornbys in every way but shows every evidence of a reversal of lines 3&4 despite the normal power up and the fact that my testset says it is not reversed.
An 6P4A RJ cable is rightly an RJ11. My Toulousian expert has now gone to great lengths to explain that a cable with a male RJ at both ends where the cores appear in the same sequence 1-6 is called tout droit (straight through) but the plugs are mounted one up and one down! The arrangement with both plugs in the plane is referred to as crois=E9 or crossed.
I still await a reply from Hornby regarding why merely plugging in one end of an RJ cable should block the comms. Reading back through several forums produces a long list of DIY chaps who have hit snags ,sometimes due to terminology but more often to equipment intolerance.
Reply to
Sailor
=3D=3D=3D=3D=3D=3D
That's RS232 wiring, a completely different beast. In that case the cables were as described but the equipment could be either DTE or DCE. A lot of people ignore that and end up with crossover cables or "null modem" or "gender bender" connectors.
MBQ
Reply to
manatbandq
That's RS232 wiring, a completely different beast. In that case the cables were as described but the equipment could be either DTE or DCE. A lot of people ignore that and end up with crossover cables or "null modem" or "gender bender" connectors.
MBQ
====================================
Very true, but then from the lenz description it seems these are the same apart from physical side of course.
Cheers, Simon
Reply to
simon

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