Product Overview

SITRANS TH420 combines perfect measurement and intelligence at any temperature and condition, ensuring high availability with its dual sensor input including 4-wire sensor connection and hot backup function. In case of a sensor failure, the transmitter automatically switches to the second sensor, and the values continue to be recorded seamlessly and without loss.

Benefits

• High availability during measurement by hot backup function.
• High reliability and long-term stability – sensor trim (Callendar-van-Dusen) and sensor drift detection for high accuracy and accelerated calibration time.
• Avoidance of production stop because of measurement failures.
• Best cost-benefit ratio for facility management.
• Cost reduction through anticipatory maintenance.
• Withstanding safety-critical environments - Extended temperature range down to -50°C and SIL2/3 approvals (HART only).

Technical Specifications

Specification	Value
Input	Resistance thermometers, thermocouples, resistance-type sensors, DC sources
Output	HART, Profibus PA
Operational temperature	Standard: -50 … +85 °C (-58 … +185 °F) SIL: -40 … +80 °C (-40 … 176 °F)
Approvals	ATEX, IECEx, FM, CSA, EACEx, NEPSI, Inmetro
Certificates	SIL 2/3 certification (HART only)
Special Features	Dual sensor input with hot backup, sensor trim, sensor drift detection