• mA, V, RTD, TC, NPN/PNP, potentiometer, & AC inputs
  • 0 or 4 to 20mA or 0 to 10V output optional
  • Optional 4-digit display
    • Useful for commissioning & fault finding
  • 24 to 250VAC or 19.5 to 250VDC power supply
  • Program using free Define ToolBox software download
    • Requires a USB Bridge Key
  • 35mm DIN rail mount casing (IP20 rated)
  • Designed for harsh EMC environments
  • CE approved & 5-year guarantee


The Define Instruments Sentry trip amplifier accepts analog inputs from a range of industrial sensors, including: process, temperature, flow, frequency, and voltage. Inputs are electrically isolated form the output and the power supply, avoiding the potential for signal degradation from earth loops. It is designed to monitor input signals and switch its relays on and off to provide control and alarm functions.

With the optional analog output it can convert weaker signals into standard signals such as 4 to 20mA that can transmit longer distances and interface with PLCs and SCADA systems.

The Sentry features a universal power supply for both AC mains and 24VDC applications. This means no stocking high and low voltage versions or worrying whether you've taken the right one with you to the job. It can produce 22V excitation, enough to power common sensors two-wire and transmitters.

The Sentry is simple to setup and calibrate with the help of Define's ToolBox software, which explains all the Sentry's functions and features. It has an extensive library of pre-calibrated ranges and linearization tables for advanced scaling.

In Stock

Part Number Price Available
$249.00 8 in stock
$299.00 2 in stock

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