2-channel Thermocouple Module | Modbus RTU interface TST320

Dual-Channel Thermocouple | Modbus RTU Interface TST320

TST320 is a MODBUS RTU interface module with two thermocouple inputs. Engineered for diverse industrial applications, it delivers precise temperature measurements across various thermocouple types, making it an excellent choice for industrial temperature monitoring.

This module offers unparalleled compatibility with all thermocouples - J, K, T, N, E, B, R, and S - guaranteeing seamless integration into any setup. Equipped with a 24-bit ADC featuring DSP processing and boasting ±0.1% accuracy, it ensures exceptionally precise measurements. Additionally, its ±0.19% CJC accuracy maintains reliable readings.

With an RS-485 interface accommodating up to 63 nodes, it effortlessly communicates via the Modbus RTU protocol with existing systems. The integrated 120-ohm termination resistor optimizes signal integrity, simplifying installation.

Safety remains a top priority, with a remarkable working isolation voltage of 1500Vrms, ensuring secure operation in industrial environments.

The TST320 2-channel thermocouple module empowers engineers, technicians, and decision-makers with real-time temperature data, enhancing process efficiency, product quality, and system reliability.


  • 24-bit ADC with DSP processing
  • RS-485 interface supporting up to 63 nodes
  • LED indicator displaying communication status
  • Compatibility with all types of thermocouples
  • Integrated 120-ohm termination resistor
  • Firmware update capability via the interface

2-channel thermocouple module applications

  • Industrial temperature monitoring
  • HVAC system control
  • Laboratory and research applications
  • Food and beverage industry
  • Building management systems
  • Automotive industry

TST320 can be used with

  • Energy monitoring module TCW260
  • Industrial IoT module TCW242
  • Third-party MODBUS RTU master devices

Technical Properties:

  • Physical characteristics
  • Dimensions: 35x86x59mm (2 module enclosure)
  • Weight: 75g
  • Mounting: On 35 mm DIN top-hat rail
  • Environmental limits
  • Operating temperature range: -20 to 60°C
  • Operating relative humidity range: 10 to 90% (non-condensing)
  • Storage temperature range: -25 to 65°C
  • Storage relative humidity range: 5 to 95% (non-condensing)
  • Ingress protection: IP40 (connections IP20)
  • Power supply
  • Operating voltage range (including -15/+20% according to IEC 62368-1): 5 to 30VDC
  • Current consumption: 15mA@12V
  • Thermocouples
  • Thermocouple types supported: J, K, T, N, E, B, R, and S
  • Temperature resolution: 0.01°
  • ADC conversation accuracy (max): ±0.1%
  • CJC accuracy (max): ±0.19%
  • Input conversion rate for both channels: 1 sample per second
    With DSP (Digital Signal Processing) over 76865 samples for low-pass filtering and 50/60Hz notch filtering
  • Thermocouple break detection: Available
  • Interface
  • Protocol: Modbus RTU
  • Physical layer: RS-485 serial line
  • Number of bus transceivers: up to 63
  • Bus cable: Twisted, shielded, 2×0.5mm²
  • Response time ≤ 50ms
  • Master response time-out ≥ Response time + Answer time
  • The answer time depends on the number of bits and the baud rate.
  • Connectors
  • Type: 3.81mm pitch screwless pluggable for 28 to 16 (AWG) / 0.081 to 1.31 (mm²) wires
  • Isolation
  • Maximum working isolation voltage: 1500Vrms
  • Warranty
  • Warranty period: 3 years