Carel IR33B9MR20 Universal Process Controller

Overview

The Carel IR33B9MR20 is a panel-mounted universal PID controller from the Carel IR33 series. It operates on 24 VAC/DC power supply and supports universal sensor inputs including NTC, PTC, Pt1000, thermocouple J/K and 4–20 mA analog signals. This unit is equipped with one relay output and one 0–10 V analog output, plus digital input terminals for remote enable or alarm functions. The integrated buzzer and IR receiver support local alarm notification and infrared remote operation. It is widely used for refrigeration cabinets, chillers, drying skids, HVAC and general thermal process control, and supplied as spare replacement for original Carel control systems.

Features

The Carel IR33B9MR20 is an IR33 universal PID controller for refrigeration and thermal processes.IR33B9MR20 accepts multi-type universal sensor input for flexible sensor matching. Hybrid output configuration: relay contact and 0–10 V analog modulating output. Built-in buzzer alarm and infrared receiver for remote parameter operation. Digital display and front panel keys for local setpoint adjustment and fault checking. Panel cutout installation, compact 76.2 × 34.2 mm form factor. Front panel IP65 protection against dust and splashing water. Compliant with CE, RoHS and industrial EMC standards.

Specs

Device Type: Universal PID Process Controller Model: Carel IR33B9MR20 Brand: Carel Series: IR33 Power supply: 24 V AC / DC Input: Universal NTC / PTC / Pt1000 / TC J-K / 4–20 mA Output: 1 x relay, 1 x 0–10 V analog Extra function: Buzzer, IR receiver Mounting: Panel cutout Front protection: IP65 Status: Obsolete legacy spare controller

Principle

The Carel IR33B9MR20 samples the measured value from temperature or process sensors, compares it with the setpoint and calculates PID output. It drives relay contacts for on/off control or 0–10 V analog signal for continuous modulation of actuators such as electronic expansion valves, heaters and fans, stabilizing temperature and process value.

Applications

The Carel IR33B9MR20 is used for temperature control of refrigerated display cases, chillers, drying ovens, reaction skids and HVAC equipment. The IR33B9MR20 is stocked as spare replacement for Carel IR33 control loops.