Adding a third keypad to a Caddx NX-8, wiring help requested!
Aug 17, 2005 69 Replies
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Robert L Bass
Most likely you screwed up the connection or broke the conductor, causing the initial problem. There is no benefit to using stranded wire (unless you have trouble stripping wire without cutting the core).
That's a Caddx keypad problem -- not a wire problem.
Regards, Robert L Bass
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The house we purchased has a CADDX, NX-6 system. It appears that the previous...
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Karl Magnus
Perhaps not in this case, but on many systems by a certain mfg., using solid wire for the keypad run invites nightmares.
KM
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Karl Magnus
ITI Caretaker + and SX-V panels with alpha kp. The reason given from engineering:
The electron "flow" in twisted wire has a better chance of "spinning off" or keeping away, inducted interference, where sold wire (not twisted) has no "spin" and picks up interference easier.
I have seen installs where a very long keypad run with solid wire would work, but intermittently fail (false keystrokes) and replacing it with stranded/twisted never failed to fix the problems.
Of course, they could be full of s*it, but it worked. Every time.
KM
J
joe
ie. Ademco's APEX Destiny 6100 [musta been where I came up with the idea as I have one in my house], 2100, along with some boat and RV systems and gate/perimeter systems, Lenel Command keypads, IEI 232iLM keypad, etc.
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cctvbahamas
it "reduces" it, but doesn't get rid of it. Run a piece of cat5 close enough to a florescent light, connect a couple passive baluns and a camera, and watch it "scroll" :-)
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Robert L Bass
Please be specific. Which manufacturer is that?
Regards, Robert L Bass
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Karl Magnus
I guess you are smarter than the team of engineers at ITI who developed the keypad data protocol then.
(Snicker)
Foam Duck you are!
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Robert L Bass
Whoever told you that is almost as FOS as Olson. It's utter nonsense.
You're mistaken. If there was a difference it was due to some other change of which you were not aware.
They are.
You probably had a bad connection. When you ran the new wire you made it better.
Regards, Robert L ass
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Robert L Bass
The idea is pure nonsense, regardless where you came up with it.
Regards, Robert L Bass
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Karl Magnus
Other types of wire you may need to know about include shielded, twisted, and stranded. Shielded wire traps and drains (among other things) RF interference and AC induction away from sensitive data circuits. Remember to ground only one side of the shield to an earth ground connection. Grounding both sides to the ground creates a giant dipole antenna and introduces damaging interference instead of draining it away. Twisted wire reduces the amount of interference, but just not as effectively as shielded.
from:
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I guess they are also lying when they say this. "Twisted wire reduces the amound of interference...."
F
Frank Olson
When-ever Robert's confronted regarding his outrageous behaviour in Usenet, he frequently resorts to posting nonsense like this. Doug L.'s classic post bears repeating here:
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joe
tell it to Ademco, smartbAss I'm sure the engineers who designed the system will run out and change their installation instructions when they find out you think it is nonsense. NOT
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Robert L Bass
Nope, but certainly smart enough to recognize that the so-called "recommendation" is pure BS. No team of engineers at ITI or anywhere else ever said that. There is no keypad data protocol that requires stranded wire instead of solid and the story about electrons spinning better on stranded cable is absolute drivel.
Indeed
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Robert L Bass
Use shielded cable for keypads *only* if the manufacturer specifies it. Some systems are actually made worse by using shielded cable. In most cases it is not recommended by the manufacturers.
What's an "amound" of interference?
You're confusing stranded wire with twisted pair cable. I said nothing about TP cable. However, now that you mention it, there are also some systems commonly installed by alarm companies which are better off using parallel (non-twisted) cable.
By the way, the guy who wrote the page you cut and pasted above isn't an engineer. He's just an installer who wrote an article for an online magazine.
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Robert L Bass
The suggestion is for 4-conductor, stranded wire. It says nothing about electrons spinning better than on solid or any other such nonsense.
You're confusing the statement about your junk science BS with a condemnation of stranded wire. I only said that the story about electrons was pure BS.
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joe
Thanks you for agreeing with me that that is what Ademco recommends.
It says
Neither did I.
You seem to be confused. I never said anything about electrons. Just stated what Ademco recommends. Now just so you won't be confused, this is what I say: Solid wire is better at higher frequencies and for back bone applications. Stranded is more flexible and better for patch cords, its use should be kept to a minimum in comm circuits because of its greater attenuation characteristics. Have a nice day:)
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Russell Brill
Tech support for the GE Networx line of panels stated; "Never use shielded cable for any data bus device"..... That's the only wiring restriction for their keypads....
Regards, Russ
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Karl Magnus
And neither did I. I never said "electrons spin better"...try again foam duck!
Can un-twisted wire be used?
Some customers have successfully used un-twisted wire at short distances. NVT does not recommend it due to its interference susceptibility.
The point is (and always was), that twisted wire provides better resistance to interference.
I have personally witnessed at least 10 keypads that would do very strange things when using solid wire. Things that can't be caused by "bad connections" as you try to spin it.
ie: Fire alarm panic button keypresses being registered at the panel, user codes that work 80% of the time on the first try.....
Plus, you are lying when you say ITI engineers never said that. I was there, you were not. (Also, the president of ITI and VP of Dealer Sales were there...didn't see you!)
Oh yea, ITI has a policy of not hiring felons....so I guess I can give you a break, you had no way of being there.
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Karl Magnus
Twisted pair cabling is a common form of wiring in which two conductors are wound around each other for the purposes of canceling out electromagnetic interference known as crosstalk. The number of twists per meter make up part of the specification for a given type of cable. The greater the number of twists, the more crosstalk is reduced.
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petem
"Karl Magnus" a écrit dans le message de news: vuBNe.37819$ snipped-for-privacy@bignews1.bellsouth.net...
Twisted mean twisted pair or wire like in a cat5 cable each pair of wire is twisted together..
this is not stranded wire..by the way,stranded wire is more flexible then solid wire and that's the only difference.. on a same gauge of wire stranded or not there is no difference in how the current/voltage of the signal in it will react..up to a certain frequency..
but the frequency where the difference start to be a problem is in the high uhf band..
I know about this cause I work a lot with transmission line in my hobby(ham radio)
the way twisted pair works,that helps sending data on long run,is simple...if you run 2 wire side by side for long,there will be capacitive effect that will form.the capacitance will affect the signal sent by distorting it..
Now if you introduce the twisting of the pair will had a coiling effect,in electronics class we learn that capacitance and inductance are inverse and fighting each other...so the twisted pair cable will have a tendency to have a controlled impedance what ever the length,that's in theory but it is working a lot better then straight wire when sending data..
of course you have to be careful about the uses of twisted pair wiring..cause its been known to engineer that build control panel that simple JKT induce capacitance so they build there circuit to compensate it..(adding inductance to it)
you can learn about capacitance here:
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for inductance here:
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you can learn about the way current/voltage/frequency will react together here: (reactance)
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