The EVD evolution driver can control an electronic expansion valve in a refrigerant circuit with Digital Scroll compressor, if integrated with a specific CAREL controller via LAN.
In addition, it features adaptive control that can evaluate the effectiveness of superheat control and if necessary activate one or more tuning procedures. Together with superheat control, it can manage an auxiliary control function selected between condensing temperature protection and “modulating thermostat”.
As regards network connectivity, the driver can be connected to either of the following:
• a pCO programmable controller to manage the controller via pLAN, tLAN and RS485/Modbus®;
• a PlantVisorPRO supervisor via RS485/Modbus®. In this case, On/Off control is performed via digital input 1 or 2, if suitably configured.
As well as control start/stop, digital inputs 1 and 2 can be configured for the following:
- optimised valve control after defrost;
- Valve forced open (100%);
- control backup;
- control safety;
- optimised defrost management.
EVD evolution comes with a LED board to indicate the operating status, or a graphic display (accessory) that can be used to perform installation, following a guided commissioning procedure involving setting just 4 parameters:
- pressure probe
- type of main control (chiller, showcase, etc.).
The procedure can also be used to check that the probe and valve motor wiring is correct.
Once installation is complete, the display can be removed, as it is not necessary for the operation of the driver, or alternatively kept in place to display the significant system variables, any alarms and when necessary set the control parameters.