TOXALERT MODEL TOX-OXY2
GUIDE SPECIFICATION
OXYGEN DEPLETION DETECTION & CONTROL SYSTEM

The oxygen sensor(s) shall have a range of 0 to 25% and a linear 4 to 20 mA or 0 to 5 vdc output signal over its range. The sensor shall be housed in an industrial style explosion proof housing. The sensing element shall be electro-chemical diffusion barrier type and be designed for ten (10) year element life. Sensors with a one year plus or minus six *6) months expected life are not acceptable. The sensor shall be powered by low voltage and its 4 to 20 mA (0 to 5 vdc) output shall be directly proportional to the percent of oxygen being detected. When sensor fails it shall drive its output signal to zero indicating alarm condition.

The oxygen sensor shall have the following diagnostic light emitting diodes (LED's):

1. Power
2. Sensor Failure
3. LOOP UP (LED varies in intensity diciating 4 to 20 mA loop current to controller).

The controller shall be designed to be mounted outside of the mechanical room and shall have two modes of control. The first mode, "warning" shall light an amber warning lamp and start the mechanical room ventilation (or purge) system. The second mode, "alarm," shall light a red alarm light and sound the audible alarm. The audible alarm shall have momentary push button silence switch to silence the audible portion of the alarm. The audible alarm, after being silenced, shall automatically reset and sound again at the next alarm occurrence.

When the oxygen level drops to 19.5% the "warning" mode shall be activated. When the oxygen level drops to 18.5% the alarm mode shall be activated. Contact outputs shall be supplied for "warning" and "alarm" modes.

The controller shall have dry contacts on both the warning and alarm stages to interface to the facility EMS.

The controller panel front shall include the following labeled indicator lights and control switches:

1. Power to system light.
2. Labeled "warning" level indicator light for each sensor.
3. Labeled "alarm" level indicator light for each sensor.
4. Audible alarm & silence push button.
5. Purge switch to manually activate the mechanical room ventilation equipment.
6. Sensor malfunction light.

Note for specifying engineer: The following are options you may want to specify.

OPTIONS:

1. digital value display for visual indication of oxygen concentration
2. Red Alarm strobe light on top of controller
3. Remote Alarm Panel.

Provide LCD digital value display on the face of the controller for each gas being monitored. The display shall read in percent of oxygen.

Provide a remote visual and audible alarm and locate (where).
(Maximum 1000 feet away from control unit).