• Intrinsically Safe Humidity and Temperature Transmitter
• Electrical equipments for use in potentially explosive atmospheres
• Potentially explosive atmosphere
• T311xEx transmitters are intrinsically safe
• The principle of intrinsic safety equipment

Programmable transmitters T3110Ex, T3111Ex, T3113Ex with 4-20 mA outputs are designed for measurement of relative humidity and temperature in potentially explosive environments.

Electrical equipments for use in potentially explosive atmospheres Special devices that can be a source of potential danger. Such devices must be designed, installed, operated, and maintained so as to not cause an explosion in potentially explosive atmosphere. The basic information about equipments intended for use in the potentially explosive atmosphere contains 94/9/EC (ATEX) Directive.

Potentially explosive atmosphere

An area, in which could be present a mixture of air and flammable substances (gas, vapor, mist, combustible dust) in such concentration, that it may catch fire. Explosion may be initiated by a spark or hot surface.

T311xEx transmitters are intrinsically safe

It is a way of equipment protection, which is based on the limitation of energy (electrical and thermal) at a level lower than the level that could cause ignition of a specific hazardous atmospheric mixture.

The principle of intrinsic safety equipment

Lies in limitation of the amount of electric energy supplied to electric circuits from power source and energy accumulated into parts of electric circuits. Intrinsically safe zener barriers and intrinsically safe isolation amplifiers are elemental types of intrinsically safe interfaces designed to protect electrical circuits installed in potentially hazardous areas.

Hazardous and Safe Area

A programmable temperature and humidity transmitter are equipped with temperature and relative humidity sensors.

Measured values are also converted to other humidity interpretations - dew point temperature, absolute humidity, specific humidity, mixing ratio, or specific enthalpy. Degrees Celsius and Fahrenheit are user selectable.

The transmitter contains microprocessor-based control circuitry in a durable plastic case with connection terminals and sensors in a filter with stainless steel mesh. Humidity transmitters are equipped with two galvanic isolated 4-20mA outputs. Configuration of outputs and output range is user adjustable. Large dual-line LCD for simultaneous display of T+RH or other humidity interpretation is an advantage. The display is possible to switch off. The computerized design ensures temperature compensation of the humidity sensor and fails indication. State-of-the-art capacitive polymer sensor ensures excellent calibration long-term stability, inertia against water, and condensation. Transmitters are designed for use in non-aggressive environments.