NX-6 -- replace NX-408 with NX-458

[broadbandwizard]

I have a 2005 Caddx NX-6 with an NX-108, three NX-450 door sensors, three NX-487 Glass Break sensors and two NX-470 4 button keyfobs.  My 408 receiver seems to be losing sensitivity because my front door sensor causes the zone 1 light on my keypad to blink slowly after the door is closed if you leave the door open too long.  One night the alarm began to chirp while it was armed, and the zone 1 light was repidly blinking on and off.  I replaced the sensor batteries, but that only worked for a couple of weeks.  Last night, the zone 1 light started the rapid blinking again.  I made the decision to replace the receiver since a replacement door sensor did not help.  If this logic passes the sanity test, my problem is now how to replace the receiver and reprogram the system to accept the new board.  I also have picked up a 2 wire smoke, NX-521B that I want to connect to the system.

Does my diagnosis of a weak receiver make sense?  I have an NX-586 and have saved the programming with DL-900.  I am pretty sure that I can't reuse the same programming for the new receiver, so can anyone give me some guidance on how to safely switch receivers and add the new smoke?  I understand that there might be some switch settings and critical programming changes to enable the receiver to overlap hardwired zones.

I read the NX-6 thread by depak74 and Fostiras on Sept 24 - Oct 13, 2009, which was helpful but not what I need.   I have not been able to find anything specific.  Also, if the receiver is indeed weak, I noticed that GE says that they can be returned for repair.  Does anyone have any experience with this?

Thanks

[fostiras]

Hi and welcome to our forum,
I assume your problematic sensor is the one with the greatest distance from your receiver. I never experienced any sensitivity loss with the NX-408/416/448 receivers.
Some points to check:
*Check the power voltage on the receiver terminal (should be around 13 volts).
* If the receiver is installed inside the panel box check that both antennas do not touch the metal box as they come out through the holes. Also check the 2 screws that hold the receiver on the box. These screws do not only hold the receiver but serve as a ground plane for both antennas. So be sure there is continuity from the screw terminals (on the receiver) to the metal box. The box is painted and sometimes there is resistance on this connection.
*Did you put anything near the panel like a new wall or big furniture or metal shelves etc. ?

If you are going to replace the receiver with the same type (408) you can use the upload module function and upload the old NX-408 data from your PC (DL900) to the new one. Be sure to have the same dip switch address setting on the new receiver as the old one.

Waiting for your feedback
Regards
george

[broadbandwizard]

Hi George, thanks for the reply.

I have a few corrections for my original posting.  The system is probably a 2002 model, not 2005.  I was under the impression that the NX-408 was no longer available, so I purchased an NX-458 which was listed in my subject line but dropped when I had to retype my posting due to being logged out automatically.  When I retyped my post, I missed that detail.

You are correct, the problematic sensor is the one that is farthest away from the receiver, but it is only one floor and perhaps 20 to 25 feet (5 - 6 meters) line of sight.  I checked the voltage as you suggested, and it measures 13.69 volts.  The screws are shiny and clean and measure 000K ohms with the same digital volt/ohm meter.  I also verified that the antennas are not shorting out against the cabinet.  They are also shiny where they go into the jacks, and the plastic insulation is in perfect condition.

To the best of my knowledge nothing has been added to the house in the way of walls, furniture, or metal shelves that are near the panel or between it and the problem door sensor.    The panel was installed by a company with one antenna about  2 inches from a rectangular vertical steel support and the second antenna was (whatever the antenna spacing is) further from the pole.  The system worked correctly for perhaps 4 or 5 years.  When this problem started, I remounted the panel to get more spacing from the pole, but it is still less than 10 inches from either antenna, but the pole is not in the path to the problem sensor.

I did buy a NX-469 case to remount the receiver away from the panel, but I wasn't sure if I could relocate it without causing the antenna tuning to be different or whether I needed to add a ground plane.  Thanks, Bob
 

[fostiras]

Hi Bob,
5 to 6 meters is nothing compared to 4 stories steel/concrete buildings I use to install these receivers in. So in my humble opinion a reposition is not necessary.

Since we are talking about zone 1, what is connected on the zone 1 panel terminals ?
One way of testing if zone 1 is functioning correctly is to disable the transmitter inside the receiver's configuration and short/open zone 1 panel terminal with the nearby COM terminal with a 3,3K resistor.

If you pass the hardwired test successfully leave the resistor across zone 1 and COM and enable your transmitter. Now check the wireless portion of zone 1.


The enable/disable transmitter feature is option 1 of segment 1 of location 01 (for zone 1). Press :

* 8       enter program code
9713     default program code
                                            DIP switch     1       2       3  
  32 #      NX-408 address                     32 =   ON    OFF   OFF
                                                     33 =   OFF   ON     OFF
                                                     34 =    ON    ON     OFF
                                                     35 =   OFF   OFF    OFF
  01 #    enter location 01  for zone 1
            if zone light 1 is ON the transmitter is enabled, press :
  1        to toggle and disable the transmitter
  *        save the edit
  #        exit location 01
 EXIT     address 32 (or 33 or 34 or 35)
 EXIT     program mode

Wait 12 seconds for the system to enroll and clear the service light.
Use the same procedure to enable back your zone 1 transmitter.

Are you using any hardwired zones ?
Do you have an external hardwired contact sensor connected to your zone 1 wireless transmitter or are you using it's own contact ?

Waiting for your feedback
george

[broadbandwizard]

Hi George,

I am sorry to be late getting back to you, my Internet connection has been down a lot for some reason.  I am working on getting some kind of back up connection.

Good to know that my distance it not marginal, which seemed logical since the system has worked well for 4 - 5 years until this started to happen.

My system has no hardwired zones.  I bought the previously mentioned NX-521B smoke detector to add it, and more later if I was successful in avoiding problems. 

My receiver has four switches instead of three as you mentioned.  I just assume that it is an NX-408 because I recall looking it up once when we talked last year.  All four of the switches are off.

After I did the things you mentioned to test for power and ground connections, I have not had any light blinking problems.  I wonder if something was not making a good connection either in the ground screws or the antennas.  I wiggled and poked plus pulled the antennas out and reinserted them to verify that they were not corroded as you said to do.

I do have another question, however.  If this is indeed an NX-408 receiver and I have four NX-450 door sensors (I found another one on an unused door about 12 meters away and it was also marginal), three NX-487 Glass Break sensors and two (possibly three) NX-470 4 button keyfobs.   I mention these again because they total more than 8. Thanks, Bob

[broadbandwizard]

George, I spoke too soon.  The zone one light is blinking again.  Whatever was wrong is still wrong.  Messing with it and checking the antennas for shorts, etc, did not fix anything.

I do have 2.6ghz routers on my computer network, but the sensors work at 319 mhz so I don't expect them to be a problem, or should I??
Bob

[fostiras]

I just mentioned 3 of the 4 DIP switches because the forth switch is irrelevant to the addressing of the receiver.

If you have more than 8 wireless zones ten you have probably an NX-416 receiver (although the NX-6 is a 6/12 hardwired zones panel it gets a 16 wireless zones panel with the NX-416 receiver).

If you only use wireless disable - in programming - all hardwired zones.

You can't fully delete a transmitter through keypad programming.

I suggest you do a full reset of the receiver (clearing all learned transmitters).
Take off all batteries from the transmitters - except the key fobs.
Put back one battery at a time and learn one transmitter at a time to the receiver.
Learn the entrance door transmitter to another zone, like say zone 16.
Even if you finally have to replace your receiver, you will need to be familiar with the above steps. Don't use DL900 for the learning process - use the keypad.

george