A question about coding

This question might sound stupid to everybody who actually works on fire alarm systems, but since I can only watch YouTube videos and make comments, I need a question answered.

Say you have a system that has many old horns and newer horns, but that newer horn can’t be set to code-3 by itself. Is there any way you can panel code just that the newer alarms to make them code-3 while the older horns stay on a continuous tone, or would the whole system have to be changed to code-3 to get the newer alarms to sound on code-3?

It is possible on nearly all panels to have one NAC do continuous and another do code 3. The only one I think of where it is “one or the other but not both” is the Simplex 2001. (btw, there was a Code 3 retrofit card made for the 2001 after it was discontinued)

If the newer horn/strobes are not capable of coding themselves in Code 3 then that means they are either old horn/strobes made before self-coding signals were invented (such as a Gentex GMS or Simplex 4903), or Simplex TrueAlerts.

Provided the horn and strobe circuits are wired separately, which usually in these older systems they are not, then you could do it. However in certain situations I have heard of coding being grandfathered due to physical limitations of the circuits (if you code a strobe in code 3 it may not work properly depending on how the flashing circuit works).

Finally, there is also the chance that the newer signals were added to existing NACs with older horns… and in this case you couldn’t do it. Without seeing the system in person it’s hard to judge.

Normally you would just pull a new circuit or add an extender panel to drive the new devices. Usually there’s only 10 or so devices on a circuit, often its easier just to replace them all with newer devices if they are that out of date and the owner wants to upgrade to code-3. Each extender panel can be set up to do whatever you want it to do.

With strobes, mixing and matching old with new or different brands on the same circuit is a huge no-no because it causes sync issues. You’d only do this if you specifically know they use the same sync protocol, like an older wheelock device with the wheelock sync protocol works fine with a new one with the same protocol.

When I say extender panel/booster panel/remote power supply/NAC power supply/etc. what I mean is one of these activated by a relay or circuit from the fire alarm panel:
http://www.cooperindustries.com/content/public/en/safety/notification/products/life_safety_notification/wheelock_8-amp_powersupply.html

http://sbt.siemens.com/FIS/productdoc/catalogs/3362.pdf

Actually it was easy to wire a full size 2001-8001 panel for both continuous ring and coded (MT, temporal, etc.) signaling. The NAC modules for each signaling type had to be on different card racks. Continuous ring NAC modules closer to the control module rack and coded NAC modules on racks further down the panel. The wiring buss that drives the NAC relays could be separated in the 10 wire harness on the left side of the panel. A 2001-8023 expanded repack could also be split because there were jumpers on the motherboard that could separate the buss wiring on the upper and lower rows of card slots. The one row 2001-8021 was all one way or the other. However, a MT module could be installed to drive an off board relay for continuous ring horns and unsupervised incandescent flashing lights which were allowed in those years.

I have a pdf scan of the 2001-3053 Temporal Code 3 Module Description. The document is dated 8/84. The 2001 was in the sales catalog until 1988 when the first version of 4100 was introduced. Production continued for some time after that for existing orders that could not be upgraded to the 4100 or for audio systems which were not in 4100 version 1.

Could you panel code TrueAlerts or a singular TrueAlert to code-3 while keeping the rest of the horns on continuous?

Not if they were on the same NAC. You’d have to separate the coded horns and continuous horns to two different NAC’s.

Well if it was the Addressable line of TrueAlerts?

I think you may be able to do that using custom SMPL programming, but I can’t say for sure. The only use I can see for it might be a Canadian two-stage setup with zoned evacuation.

Would you need a separate panel?

No, as long as the panel can code each NAC separately, which most of them can.

Ahh this answers my question of why some 2901-9838/-9840s in my school do code 3 while the rest do continuous. Thanks!

Which ones do code-3?

Assuming you were talking to me, but I may be wrong. A few upstairs classrooms at the back of the school do code 3, while the rest of the school are on continuous. All indoor alarms are -9840s, all outdoor are -9838s, except for one replacement MT which is on continuous horn.