Bosch 2000, shared Zone inputs, Monitor Zone state, possible?


I have a relatively new Bosch 2000 alarm system that I'd like to add some smart functionality to, while keeping it "independently" functional. The Bosch 2000 is an 8 Zone system, however there are only 4 physical zone inputs - each physical zone input manages 2 zones which are differentiated through the use of different resistors (3K3 for one zone and 6K8 for the other zone).

So, the zone configuration looks as follows:

• Z1 PHYSICAL INPUT = Zone 1 (3K3 Resistor) and Zone 5 (6K8 Resistor)
• Z2 PHYSICAL INPUT = Zone 2 (3K3 Resistor) and Zone 6 (6K8 Resistor)
• Z3 PHYSICAL INPUT = Zone 3 (3K3 Resistor) and Zone 7 (6K8 Resistor)
• Z4 PHYSICAL INPUT = Zone 4 (3K3 Resistor) and Zone 8 (6K8 Resistor)

I am currently using 5 of the allocated Zones:

• Zone 1 = Front Door sensor
• Zone 2 to 5 = PIR motion sensors
• Zone 8 = External siren box tamper sensor

I'm considering buying a 12 Zone interface kit because I'd like to be able to (i) monitor each of the zones sensors and use their state to trigger home automations (in Home Assistant), (ii)  monitor alarm state (on/off) and (iii) arm/disarm the system remotely, (iv) receive alerts if the alarm is going off.

I've tried to read as much as I can, but I'm still unsure of several things, namely:

1. Can the Konnected interface kit handle the shared/split Zone arrangement of the Bosch alarm systems?
2. Can I independently monitor the state of 2 Zone sensors connected to the one physical zone input terminal?

Any advice or information anyone can provide would be greatly appreciated.

Cheers, Rich

  • Based on my experience, it won't distinguish the sensors when you put your jumper wire into the terminal (as you use zone-doubling). However, an idea come up into my head... Let's take zone 1 and 5 as an example, I'm thinking what would happen if you pull out zone 1 & 5 wires and put them into the interface module first (into two seperate zones), then join them together back to the PHYSICAL ZONE 1. Would Konnected system pick up two zones seperately? 

  • Would love to know the answer on this one :) I assume with some twiddling you could tune two zones on the interface module to be sensitive to the different double zone resistances when one or the other triggers. Might give that a try and report back.

  • @Brendon Please do, whether or not the interface board can handle this will be what makes or breaks my decision to buy a konnected setup

  • It kind of worked but not 100%. There are 4 possible states when there are two sensors and I could get 3 of them working. I forget which state didn't work. I don't think the pots on the interface board are sensitive enough to be able to tune for the resistance differences between each state. I certainly wouldn't get the Konnected board if you have a lot of doubled zones. I ended up being able to split the two tamper zones because the Solution 3000 has an on-board tamper zone that wasn't being used. You could look at forking for a Solution 3000 instead which supports 8 zones plus a tamper? Alternatively you could ditch the Solution 2000 and just use the Konnected unit as the main alarm. All that you lose is the keypad and perhaps your RF remotes, though the phone app largely takes care of that and Siri makes triggering things pretty easy.

    I've persisted with the integration mostly out of curiosity and challenge, and it certainly has been challenging! :D

  • I’m in this situation at the moment trying to get the zone doubling to work on my interface board and Bosch sol 16+. I can think of a way to test which I believe will work. Connect your sensor lines with EOLR resisters to the Interface board directly and individually. Then run a line back from each of the inputs on the Interface board back to your Bosch panel and double zone it back, but this time add a Diode from each of the lines before joining them to the Bosch zone inputs - that way neither signals can interfere with each of the sensor lines or Interface inputs. Will try this out today.
  • Update, the Bosch faults using the diode as it thinks its an open circuit. I have the interface hooked up doubling the zones as per the Bosch, sharing zones - which is acceptable to me. Ie bedroom 1/entry door status is as one. I have many other zones sharing aswell. I may reconfigure some zones so they reflect the multiple entry door rather than combining with motion sensors.. this will suffice until I’m ready to replace the Bosch entirely with the Konnected pro panel.
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