How energy efficiency is improved
Protected, intelligent solution for optimal energy use.
Areas of application
As a bi-directional receiving station for the signals from the analogue LRT410 room thermostats and the digital LRA420 and LRA450 room operating units, the LET4*** is used as a single-room controller for every channel and for activating thermal actuators in underfloor heating control systems. The individual controllers communicate using a bi-directional signal. The pulses of the radio thermostats can be individually assigned to the corresponding channels.
Properties
- Intelligent bi-directional wireless controllers for heating/cooling
- Reception frequency: 868.3 MHz
- Versions with or without LAN connection
- LEDs for the functions, communication and operating modes
- One LED per channel for visualisation and confirmation of the channel assignment
- Emergency function when there is no signal reception
- Individual configuration for every channel accessible from the outside
- Integrated pump logic and potential-free output contact
- With heating/cooling input and potential-free and configurable output
- Input for monitoring the supply temperature
- Input for monitoring the relative humidity
Technical description
- Black housing (RAL9005) with transparent cover
- Versions with 4, 8 and 12 channels
- Including a transformer for the 24 V version
- Monitoring of the inputs and state of the controller with LEDs
- 24 V version with triac outputs for thermal actuators
- 230 V version with relay outputs for thermal actuators
- Automatic connection terminal, depending on the channel, 1 or 2 actuators/channel
- Maximum number of thermal actuators with 12-channel version: 16
- SD card for software update accessible from the outside