Connecting to cooling controller Danfoss AK-CC 550
Increasing demand for the refrigeration quality ( keeping optimal product storage temperature) and efficiency (minimizing power consumption) enforces introduction of the scada/monitoring systems which would helped to track malfanctions in time, detect abnormal situation and operation modes, provide analityics for resousrce consumption, or even optimize resource consumption using different strategies.
For now, almost every vendor for the cooling equipment provides web-based solution for monitoring and control, but their main drawback is that they focused only on their cooling controllers - and they have to be integrated into a higher level facility monitor & management system.
With only one WebHMI it is possiblle to integrate all cooling, ligting, HVAC and other equipment into a single facility management system and link it to the upper dispatching level.
Danfoss АК-СС 550 refrigeration controllers are very popular devices applied in industrial cooling units, with some features of communication over Modbus:
- autosetup for baud rate - i.e. after the module detect 3 polls not matching own communication speed, it will change own uart's transmission rate to next option [9600, 19200, 38400]. Thus WebHMI connection may have one of these 3 speed in its settings.
- fixed data format - start bit, 8 data bits, parity bit (even), 1 stop bit
The module parameters in the user manual have an alphanumeric code, for example r14, u11. These codes are also displayed on the instrument display. The network address of the module is set in parameter o03. To obtain a Modbus parameter address, one have to subtract 1 from PNU number (Parameter number). A complete list of parameters and the corresponding PNU numbers is given in AK-CC550 Modbus Parameter Definitions document. This document is available on request . A fragment of the parameter table is presented below.
There is a video (in Russian language) with live demo of controlling Danfoss AK-CC 550, and FCS 51 frequency drive as well.
