Model C12-17 Combustible Gas Transmitter from Analytical Technology
The Model C12-17 is a stand alone gas transmitter designed to detect potentially hazardous concentrations of combustible gases in ambient air. Gases and hydrocarbon vapors such as methane, propane, butane, gasoline, toluene, hydrogen and many others can be reliably monitored in process buildings, analyzer enclosures, pump stations and gas compressor stations. In fact, anywhere gases or vapors may build up to explosive levels can be readily monitored using this transmitter.
C12-17 Combustible Gas Transmitters are three wire transmitters, operating from 24 VDC power supplies and transmitting a 4-20 mA signal proprtional to 1-100% LEL (Lower Explosive Limit) of a particular gas or vapor. The transmitter is available either as a blind transmitter or with integral LCD display that provides local indication of gas concentration, visible through the glass window in the explosion proof housing.
Units supplied with the integral display also contain a single alarm setpoint and relay for local alarm purposes. This integral is a latching alarm that can be reset with a magnetic tool without opening the enclosure.
C12-17 transmitter can be connected directly to PLC, DCS or computer based alarm systems wihtout additional hardware. If complete alarm systems are needed, ATI can supply Series B14 modular alarm receivers or Series C14 multi-point scanning alarm units to provide all required alarm functions.
Sensor Operation
Combustible gas sensors are made up of two matched sensing elements, one active and one passive. Both are electrically heated and form tow legs of a Wheatstone bridge circuit. When combustilbe gas contacts the sensor, the active element catalyzes the oxidation of gas, heating the active element and changing it's resistance. The passive element remains unchanged, resulting in a change in the bridge circuit thaqt is proportional to the gas concentration.
Explosion proof sensor assemblies are made of 316 stainless steel for maximum corrosion protection. A sinter bonded glame arrestor provides the gas diffusion path to the sensing elements while maintaining the flame proof integrity of the aseembly. Sensing elements are specially designed for maximum poison resistance and long life in harsh industrial environments, with sensor life typically 2 years or more.
Specifications
Gas Type
Calibrated for methane unless otherwise ordered
Display
3 digit LCD optional
Range
0-100% LEL
Response Time
T90 < 10 seconds
Accuracy
Generally +/-5% of value, but limited by available calibration gas accuracy
Electronic
Repeatability
+/-1%
Electronic
Lineraity
+/- 0.5%
Zero Drift
Less than 2% full scale per month
Span Drift
Less than 3% per month
Output
Powered 4-20mA, 675 ohms max at 24 VDC
Power
12-30 VDC, 100 mA maximum
Enclosure
Explosion proof, Class 1, Div 1, Groups B, C & D
Alarm
Optional single alarm available
Alarm Relay
SPDT, 5 Amp @ 220 VAC non-inductive latching
Sensor
316 stainless steel
Controls
Potentiometer zero and span adjustment
Potentionmeter alarm setpoint adjustment
Magnestic reset switch for latchning alarm relay
Operating
Temperature
-40 to 70°C
Weight
3 pounds
Ordering Information
For pricing, please call AFC International at 1-800-952-3293, 219-987-6825 or fax 219-987-6826 or email sales@afcintl.com.
AFC International, Inc.
PO Box 894, DeMotte, IN 46310
715 SW Almond St, Ste C, DeMotte, IN 46310
800-952-3293 219-987-6825 Fax 219-987-6826 eMail: sales@afcintl.com
