Biamp with fire alarm

Jubal

i have a project that the fire alarm sound is connected to a biamp. once the alarm play, other sound should be off. my problem is they didnt give us a trigger so i know the alarm is playing. they only lay down a speaker cable going to the biamp input 6.

so my question is there any command that i can do to detect if the alarm is playing already?

pdabrowski

What Biamp DSP product is being used?
Nexia, Audia or Vocia?

The main problem I see with their gear (we have about 50 audiaflex units here!) is that there is no unsolicited feedback, so having the presence of audio or not is difficult to monitor successfully without clogging up the message queue on both the AMX master and the Biamp device.

If you only have an audio input for the fire alert I would expect that the presence of audio on that input should kill all other inputs and a ducker is the DSP block component inside the DSP file that would do the job.

The only real way for the AMX master to successfully detect the presence of a fire alert is to leverage the logic output of that ducker which can then trigger a relay on a control card like the logic box (if you are uisng AudiaFlex http://biamp.com/products/audia/controls.aspx ). Other Audia devices have similar controls and may have relays integrated but the AudiaFlex does not unfortunately.

Jubal

pdabrowski wrote: »

What Biamp DSP product is being used?
Nexia, Audia or Vocia?

The main problem I see with their gear (we have about 50 audiaflex units here!) is that there is no unsolicited feedback, so having the presence of audio or not is difficult to monitor successfully without clogging up the message queue on both the AMX master and the Biamp device.

If you only have an audio input for the fire alert I would expect that the presence of audio on that input should kill all other inputs and a ducker is the DSP block component inside the DSP file that would do the job.

The only real way for the AMX master to successfully detect the presence of a fire alert is to leverage the logic output of that ducker which can then trigger a relay on a control card like the logic box (if you are uisng AudiaFlex http://biamp.com/products/audia/controls.aspx ). Other Audia devices have similar controls and may have relays integrated but the AudiaFlex does not unfortunately.

im using Biamp audia solo 8x8. i think it's hard to have setup like this if there's no contact closure to monitor the current state of the fire alarm

pdabrowski

Jubal wrote: »

im using Biamp audia solo 8x8. i think it's hard to have setup like this if there's no contact closure to monitor the current state of the fire alarm

The contact closure comes in the form of using the logic out box connected to the remote bus triggered from the ducker logic out terminal inside the DSP

You could send level requests to a meter and monitor whether there is signal or not, but as I said earlier you'd be risking clogging up the queues in both the master and the DSP.

I have no idea of what country you are in, but if the evac/fire alarm standard there doesn't require triggers such as the +24VDC circuits as specified in AS2220 (Australian) you don't have much of an option except to choose between constant level requests or adding a logic box to the install to trigger an IO on the master.

kennethk

When you already have logic from the ducker you can trigger a string out on the serial port (or am i wrong??).

Done this with Nexia, controlling stuff with serial, based on logic in dsp.

This reminds me of the fact that after reboot the Nexia sends out alot of characters, causing the Endeleo UDM (the device nexia was controlling via serial), to "freeze/crash"! ( 2 years ago that story is).



Kenneth K

pdabrowski

kennethk wrote: »

When you already have logic from the ducker you can trigger a string out on the serial port (or am i wrong??).

You're probably right, I havent played around with that myself - but reading the spec for the "command output" block I was left confused as to where the message ended up - ie; Biamp doesn't tell you where

Don DeLong

I can speak from experience that the 'Command String' logic triggered block in Audia/Nexia does send the string out the serial port. It WILL NOT send it over telnet unfortunately, which has kept me from using IP control of the Audia in many cases. This is how I would approach this system: Have a ducker in line with each input or output (whichever you're using fewer of), and connect the fire alarm signal to the 'S' (sense) input on each ducker. Use the logic out of one of the ducker blocks to connect to a command string block, and enable the logic out of the ducker block. Enter a unique string into the command string block, and have your Netlinx listen for that string on the serial port. See screenshot below:



In this example, I set the string to "'FIRE!'" but you could use whatever you wanted. In some cases, I have used the same strings as Audia responds with when polled, for instance when controlling the telephone interface, if I poll the hook state, or the hook state naturally changes (like someone hangs up on the far end of a call) I get the same feedback and update variables the same way.

A caveat of using the 'Command String' block in Audia/Nexia: it only sends the string on a change from low to high. In other words, if your Netlinx reboots and there is already a signal coming from the fire alarm, until the signal stops, then starts again, you won't know. Of course the ducker is still going to duck the program signal, but your control system won't have proper feedback. A way around this is to use a logic state block, and an AND gate to enable/disable the logic line before the 'Command String' block. Then, periodically, or on bootup, toggle the 'Logic State' from one to zero and back to one, to generate a rising edge to trigger the command string. See attached picture:



I've used this method with over 100 individual command strings to get unsolicited feedback from AudiaFusion amp channel status, while also allowing polling.

Something else to ponder: In a multi-unit Audia/Nexia system, whatever unit the 'Command String' block is allocated to is the one that outputs the serial string. You could potentially have different strings coming out of the ports of each unit if you found the need, and still send normal ATP strings to any of the units to control the system since the blocks are addressed individually by device ID.

Hope this helps,
Don