Series D12 Digital Gas Transmitter
from Analytical Technology

Loop Powered with HART - For plants operating with HART protocol communications systems, the D12 can be supplied with this option. Our HART output supports both 4-20 mA and constant current mode of operation.

Transmitter with Integral Relays - For systems requiring local alarm functions, or systems where discrete outputs are desired, the D12 can provide 3 relay outputs. Relays are assignable to any alarm set point or fault condition and are fully programmable for set point, hysteresis and time delay.

Transmitter with MODBUS - When RS-485 communication is desirable, D12 transmitters with alarm relays can be suppled with a MODBUS interface. Software supports up to 247 unique addresses for large system use.

Password Protection: Program settings stored in the transmitters may be protected by a user selectable 4-digit password. Operators may still review all functions, but changes may only be made by authorized personnel. Modular Electronics: The D12 electronic assembly plugs easily into the power supply board in the base of the enclosure. Transmitters can be removed for wiring and quickly replaced in the event of a fault condition. Explosion Proof Enclosure: Transmitters are designed for operation in hazardous areas. The case aluminum housing for the D12 transmitter is rated for Class 1, Division 1, Group B, C, D locations and is UL, FM and CSA certified. Scalable 4-20 mA: The output range for a particular sensor is programmable within the range boundaries set in that sensor.

• Three Internal Alarm Relays: Optional relay outputs can be used for local alarm functions. All relays are programmable for set point, hysteresis, on-delay, off-delay and other variables. Even a remote reset feature is provided for in the transmitter design.
• Analog Output Simulation: Transmitter analog output can be set to user definable values. This provides for complete loop testing without the need to apply gas to the sensor.
• Relay Output Simulation: Alarm relays may be activated on command to allow testing of local alarm devices. Any combination of relays may be activated based on operator selection. Output and alarms may also be inhibited for maintenance and calibration.
• Serial Communication Interface: The transmitter is available with either HART or MODBUS protocol. The Hart protocol supports the HART Universal and Common Practice Commands at 1200 baud using the Bell 202 FSK modem standard. The MODBUS protocol supports 9600 baud access to concentration and status information and supports alarm setup and many other functions on either RS-485 or RS-232(software selectable). Comes with a register/tag database on a 3 1/2" diskette.

Sensor Flexibility No matter which style of transmitter you choose, your D12 transmitter includes features that enhance performance and provide operational flexibility, starting with out own advanced electrochemical sensors. Interchangeable Sensors: Every toxic gas transmitter will accept up to 46 different sensors, greatly reducing the need for multiple transmitter models. The self aligning sensor holder simply plugs in, with automatic sensor recognition and verification when contact is made.

• Smart Sensors: Plug-in sensors store calibration data, allowing sensors to be calibrated separately from the transmitter. This allows bench calibration (or factory calibration) of sensors to reduce the necessity for carrying calibration gas around the plant. Sensors are even interchangeable with ATI's C16 PortaSens II portable gas detector.
• Calibration History: Each time a sensor is zeroed or calibrated, the data is stored in sensor memory. Calibration history can be recalled and sensor condition reviewed by operating personnel whenever necessary.

Sensor Response Verification

For many toxic and combustible gases, ATI offers a unique sensor response testing system unmatched by any competitive transmitter. Even outdoors in high wind conditions, the Auto-Test system provides reliable response checks to insure system integrity.

• Electrochemical Gas Generator: Sensor response is verified with an actual gas sample, generated on demand. Electronic sensor and circuit tests just cannot provide the same level of confidence.
• Plug-in Smart Generator: Auto-Test gas generators are easily installed and removed when necessary. Generators store run time information accessible to operators and are automatically tested for compatibility with the installed sensor.
• Auto-Test Log: Systems using the Auto-Test generators store a testing log indicating the number of tests performed as well as test results. This data is stored in individual sensor memory for later review.