Triconex 3721 Analog Input Module

Triconex 3721 Analog input module

Technical parameters

Input voltage: 0 to 5VDC or -5 to + 5VDC, ±6%.

Number of input points: 32 differential, DC coupling.

Input update rate: 10ms.

Resolution: 12-bit or 14-bit programmable.

Accuracy: Within the range of 0°C to 60°C, less than 0.15% of the full scale (FSR).

Common-mode suppression: -85dB (DC - 100Hz).

Power-off resistance: 140kΩ (DC), typical value.

Isolation between branches: 420kΩ, typical value.

Input out-of-range protection: 150VDC/115VAC continuous.

Diagnostic indicator lights: Equipped with PASS (pass), FAULT (fault), ACTIVE (active), and FIELD indicator lights.

Practical application case:

Petrochemical industry: In a certain large-scale ethylene production facility, the Triconex 3721 module is used to collect analog signals such as the temperature and pressure of the reactor and the flow rate in the pipeline. By accurately transmitting these signals to the control system, operators can monitor the key parameters during the production process in real time. Once any parameter is abnormal, the system can respond promptly, such as adjusting the feed rate or starting the cooling system, to ensure the safe and stable operation of the ethylene production process and effectively avoid equipment damage and safety accidents caused by parameter loss of control.

Power industry: In thermal power plants, the Triconex 3721 module can be used to monitor parameters such as water level, steam pressure and temperature of boilers. For example, the analog signal of the boiler water level sensor is connected to the 3721 module. The module converts the signal and transmits it to the distributed control system (DCS) of the power plant. The DCS controls the start, stop and speed of the feed water pump based on these data to maintain the boiler water level within the normal range, ensuring the safe operation of the boiler and preventing water shortage or full water accidents. This further ensures the stable power supply of the entire generator set.

Natural gas processing industry: In a certain natural gas processing plant, the Triconex system is used to build a safety instrument system, and the 3721 module is responsible for collecting analog data such as pressure, flow rate and temperature in the natural gas pipeline. These data are crucial for monitoring the transportation and processing of natural gas. By monitoring these parameters in real time, situations such as pipeline blockages and abnormal pressure can be detected promptly, ensuring the safety and efficiency of natural gas processing and transportation. At the same time, they also provide accurate data support for subsequent metering and dispatching.

Metallurgical industry: In the blast furnace ironmaking process of steel plants, the Triconex 3721 module can be used to collect analog signals such as the temperature distribution inside the blast furnace, the top pressure of the furnace, and the hot air temperature and flow rate of the hot blast stove. Based on these signals, the control system can adjust the distribution strategy, blower volume and other operational parameters of the blast furnace, optimize the blast furnace ironmaking process, improve the quality and output of molten iron, reduce energy consumption, and at the same time ensure the safety and stability of the blast furnace operation.