The CAREL IR33 series electronic temperature controller has a supply voltage rating ranging from 115VAC to 230VAC. This controller has a width of 76.2mm and a height of 34.2mm device. It has 4 relay output digital refrigeration. This single relay is perfect for controlling the minimum ON or OFF times of output to protect loads. The protection avoids control swings for more consistent and reliable functionality. The controller has a simple user interface with a clear LED screen and large control buttons.
Auto tuning
Auto tuning within the controller gives vital accuracy during configuration. The auto-tune function uses rule-based calculations typically used by experienced engineers to configure the controller either at the set-point or whilst the load is being heated from the ambient temperature.
Supplied with a default factory setting, the PID parameters allow standard control functionality but are not optimised for the system that IR33 will control. Auto-tuning the controller is used to fine-tune the 3 control parameters involved to ensure that the controller is optimised for any application.
Real-time clock
The addition of a real-time clock (RTC) to the IR33 series aids in the management of working cycles within the controller as well as to support logging alarms. The RTC in the controller is a low power resource for accurate timekeeping and freeing up system power for accurate monitoring and control.
Working cycles controlled by the IR33 can rely on the internal clock for accuracy with the ability to remain timekeeping even when the main system power source is off or unavailable.
Real-time clocks are key to an accuracy within time-based controllers and should not be confused with hardware clocks governing digital information. Real-time clocks, unlike hardware clocks, count in human time units for relative control.
Optional expansion
Suitable for use with remote controls, the IR33 series can use an infrared remote control allowing access to all main functions as well for configuring system parameters. This allows easy setup and use of all IR33 controllers from a distance.
Find the IRTRUES000 IR33 remote control here: 745-7999
Programming keys are a simple and effective way to quickly program controllers both when on and also when not connected to a power supply. This disconnected programming function can reduce the risk of errors in the controller. A programming key allows for fast and effective technical service and can be used in just a few seconds for ease.
Find the IROPZKEY00 programming key here: 745-8002

2 independent control loops
Auto-tuning PID control
Infrared receiver and buzzer
Plug-in terminals
Programming key compatibility
Real-time clock
Relay or SSR output versions
Remote control option
Temperature input or universal input

CE certified
IP10 rated
IP65 rated