The energy module enables up to 3 three-phase motor powers to be measured per module.

The energy module consists of:

  • 3 times 3 inputs for current transformers
  • 3 inputs for the grid voltage 400 V
  • 1 input for a PT100 temperature probe
  • 1 input for a 4-20 mA low-pressure sensor
  • 1 Modbus RS485 for communicating with a GTC
  • 1 set of jumpers for the addressing
  • 1 second bus for communicating with the DNI

 

The module can be parametrised from the DNI and it is possible to install other modules, for example, to measure the power consumed by 5 compressors and the condenser fans. We preferred this procedure over the approximation using the polynomial calculation of the powers of the compressors that do not allow the variations in power due to the dispersion of charge of the cylinders, the variable speed drive or the systems with screw compressors to be taken into account.
With this module, we can take into account the consumptions of the condenser fans as well as the power consumed by the pumps in indirect systems. The 4-20 mA low-pressure sensor, along with the PT100 temperature probe, allow the overheating of the compressors to be measured and the enthalpy in the intake to be calculated. You have understood properly. It is now sufficient to connect an ultrasound debimeter* to determine the mass flow of the system. The DNI will calculate the instantaneous cooling power as well as the real COP.
All of these values are directly accessible in a table in the DNI display, in which we can view the readings of the active, reactive or apparent powers. From Sentinelle, it is possible to generate a graph of powers (absorbed/cooling) with the exterior temperature, integrating the real COP.

CONDITIONING :
Before conditioning, it is possible to install a DNI with one or two energy modules and a debimeter in order to monitor the powers and the COP. After conditioning, from Sentinelle it will be easy to compare the COP of the two fluids thanks to the relational databases. It is therefore possible, for example, to guide the COP at an exterior temperature of between 15 and 20°C for both coolants.

 

* Available early 2016

Installing a DNI is MEASURING, MONITORING and REDUCING the direct (leakage) and indirect emissions, thus reducing the energy consumption.