Device Compatibility - Tec Trek Web Site

Tip of the Week

NOW FOR THE NEWSLETTER

Its not you, its me, we are just not compatible!!


Based on a recent situation offshore, I was called out to resolve a system problem that I wanted to share with you. I can say that after many years in the field, I thought that I had seen it all, well surprise.

Upon arrival, the situation I witnessed was the Fire Alarm Control Panel was in trouble and the panel alarm reset would not work after an individual added a thermal detector to the system.  Process of elimination led me to believe that the addition of the thermal was causing problems, considering everything was fine prior.

After looking at the addressable fire control system and the conventional thermal detector that was added, I bowed my head, said a small prayer and then went outside for a breath of fresh air.

The tech stated that after he connected the detector to the system, everything was fine, the devices indicator light was flashing, this indicating power was applied correctly, however when he tested the device, the red indicator on the device illuminated, but failed to produce an alarm at the FACP, but  then the panel when into immediate trouble and pressing system reset, the device remained in alarm and  would not clear and the panel remained in trouble.

On the signaling line circuit (SLC) of an addressable panel, which is the power and communications link from devices to panel, there is usable voltage to power up the device, however when testing the alarm function, the conventional device is designed to short across the circuit, this would cause a conventional panel to alarm, but would short out the communications loop (SLC) on the addressable, hence your trouble.  

The alarm reset on a conventional system will temporarily drop power to the devices, which functions as a end device reset.  However, on the addressable system, the power on the (SLC) loop is always constant, non-resetting, unless you were to power down the entire system.

So, in a nutshell, all Fire Control Systems have a documented compatibility sheet which lists devices that will work and are approved for the system.  Should it be necessary to add a device not manufactured by the same company, all addressable systems make monitoring modules that will work with a dry contact closure or if you have existing conventional devices, that require power like smoke or thermal detectors. Again view the compatibility sheet to verify that these monitoring modules are supported for these type conventional detectors.

The compatibility sheet provided by the Fire Control System Manufacture is the CYA (Cover ur a**) legal liability, so take note if its not on the list, do not use it.


If you require more information regarding the terms and explanations above, contact me by email or phone for assistance.

The above information is covered in the following Tec Trek class segments: Awareness Training (FG-01A), Basic Technical Training (FG-01)

For more information regarding training schedules and course curriculum, please visit our Web Site at www.tectrek.org

or Contact Todd Olivier at (337) 298-7959.

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Email: todd@tectrek.org