The Carel pCO2 and pCO3 controllers can be equipped by a Modbus communication card. It enables reading and writing variables prepared in the Carel controller. Some vars can be read only, some can be written – this is up to the Carel engineer. The output of the Carel delivery should be a table with three types of variables, which is used as source for SoftPLC IDE enfineering.
Carel uses three variable types: Analog, Integer, and Boolean. Analog is so called HVAC integer, i.e. signed integer with one decimal position: 201 actually means 20,1.
Analog: read Modbus function F03, write F06. All is Hi-Lo, Signed.
Addressing starts at 2, 3, 4, 5… up to 127 (?). Quantity of inputs (bytes): 2.
Set the KP parameter to 0.1, which gives the decimal point.
Integer: read Modbus function F03, write F06. All is Hi-Lo, Signed.
Addressing starts at 130, 131, 132, 133… Quantity of inputs (bytes): 2.
Boolean: read Modbus function F01, write F05.
Addressing starts at 2, 3, 4, 5… Quantity of inputs (bytes): 1.
Comm line parameters: at the Carel controller set the BMS address (Modbus slave address), Modbus protocol, and comm speed. Tested at 19200, 8, N, 1, no flow control.
The Carel controllers are used by Lennox, labeled as Climatic 50.
Any idea about Carel proprietary protocol??? I`d like to interface IR33 with microcontroller and make a small web server
According to http://www.carel.com/carelcom/web/eng/catalogo/gamma_dett.jsp?id_gamma=39&id_tipologiaProdotti=55&id_mercato=3 , it is possible to use a customized driver to interface directly the Carel internal bus. However, considering the effort – what about to use Carel configured for Modbus/RS485 and a MiniPLC as an excellent example of embedded web server, with free tools and support?
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The Domat FCR015 zone controller with UC015 room controller for CO2-based heating, cooling and air flow control comes with new firmware. It was developed mainly for more flexible manual output re-adjustment. More interesting in terms of DID control is the possibility to assign logically output sequences from PI controllers for heating, cooling and air volume. A very powerful tool is the use of combinations of these sequences.
The problem of monitoring today is not to get data, but to quickly evaluate it and take appropriate action in technology. Where is the interface between what is better left to the system and what the operator should do?
This year’s last expedition of goods will take place by December 23, 2019
This training will be a basic introduction to the Merbon IDE.
This training is marked as an ongoing training to basic Merbon IDE training.
The training is for designers of building control systems with Domat components. We will focus on the most common mistakes, the connection of analogue sensors, surge protection, powering, etc.