We had an enquiry from a customer who needed to bring an RTD reading into their PLC, but the raw resistance signal from the sensor wasn’t something the controller’s analog input card could accept directly – and running that resistance signal any distance risked measurement error from the lead wire itself.
This looks simple, but before picking a part number we’d need a few details. Which RTD type are you using – Pt100Ω, JPt100Ω, Pt50Ω, or Ni508.4Ω – and over what temperature range? What output signal does your PLC or DCS accept – 4~20mA, 0~10V, or another range? And do you have 24VDC or 12VDC available on site? The MTT MS3002 covers all four RTD types, but the exact order code depends on your specific sensor type, output, and power combination.
In actual application, the MS3002 is a terminal block type transmitter that mounts on DIN rail right where your RTD wiring terminates, converting the resistance signal into an isolated DC output before lead-wire resistance or electrical noise has a chance to affect the reading (rated for lead wire resistance up to 200Ω per wire). Input, output, and power are all isolated from each other, zero and span are field-adjustable, and response time is 170ms standard, with a 10ms high-speed version available if your process needs a faster reaction. It runs on 24VDC or 12VDC power (the 12VDC version isn’t CE marked).
From our experience, before we quote this, we would normally check your RTD type, the temperature range you’re measuring, your required output signal, your available power supply, and your lead wire length/resistance. Hope this helps.
