Introduction; Advantages; Principle; Functions - Danfoss Optyma Plus User Manual

Introduction

Application
Condensing unit control

Advantages

• Condensing pressure control in relation to outside temperature
• Fan variable speed regulation
• On/off or variable speed regulation of the compressor
• Heating element control in crankcase
• Day/night controller operation
• Built-in clock function with power reserve
• Built-in Modbus data communication
• Monitoring discharge temperature td
• Oil return management control at variable speed control

Principle

The controller receives a signal for demanded cooling, and it then
starts the compressor.
If the compressor is controlled by variable speed, the suction pres-
sure (converted to temperature) will be controlled according to a
set temperature value.
Condenser pressure regulation is performed again following a
signal from the ambient temperature sensor and the set reference.
The controller will then control the fan, which allows the condens-
ing temperature to be maintained at the desired value.
The controller can also control the heating element in the crank-
case so that oil is kept separate from the refrigerant.
For excess discharge temperature, the liquid injection will be acti-
vated in the suction line.

Functions

• Control of condensing temperature
• Control of fan speed
• On/off control or speed regulation of the compressor
• Control of heating element in crankcase
• Liquid injection into economizer port
• Raising the condenser pressure regulation reference during night
operation
• Both internal and external start/stop cooling
• Safety cut-out activated via signal from automatic safety control
Regulation reference for condensing temperature
Reference
Night offset
The controller controls the condensing temperature in relation
to the ambient temperature. A set point is entered for how much
Set Point
higher the reference must be. The reference can be raised at night.
Tamb
Day/Night
The controller has an internal clock function which changes
Day Night Day
between daytime and night operation.
During night operation, the reference is raised by the 'Night offset'
value.
This day/night signal can also be activated in two other ways:
• Via an on/off input signal - DI2
• Via data communication.
2 User Guide RS8GD602 © Danfoss 2015-10 Optyma Plus
TM