Service manual

12-4
CONTROL SYSTEM
SM CINCO 1-A.1 GB
12.2.3 Control Features
12.2.3.1 Compressor
DC brush less and sensor less motor inverter driven compressor.
12.2.3.2 Compressor Drive
DC inverter module to drive compressor.
12.2.3.3 Outdoor Fan
DC brush less motor(s) drive the outdoor unit fan(s).
12.2.3.4 RV
Reverse Valve set the direction of refrigerant flow in the system, thus setting the operation mode for cooling or
heating.
When the solenoid is powered, system will work in heat mode.
12.2.3.5 EEV
Expansion valve operated by step motor which controls the size of the orifice.
12.2.3.6 HMI
Consists of Four “7-Segments” + four push buttons for display, monitoring and setup features.
12.2.3.7 Dry Contacts
Dry contacts are used to interface the system with an external building management system (BMS).
12.2.3.7.1 ODU Dry Contacts
• Night input. Switches the system to night mode when closed. During night mode, the outdoor unit fan motor(s)
and compressor speed will be reduced in order to reduce the system noise level.
• SB input. System will be turned to Stand-by when the contact is closed.
• Power Shedding input. Limits the maximum power consumption when closed.
• Alarm output indicates a failure in the system.
Alarm output will be activated when an ODU Faults/Protections occure. Alarm output will be OFF when the
Fault/Protection is cleared.
12.2.3.7.2 IDU Dry Contacts
 Presence detector input.
12.2.3.8 Temperature Sensors
Action
CTT
OAT OCT OMT HST RGT RLT ICT RAT
Compressor Speed Cool P + + P P
Compressor Speed Dry P + + P +
Compressor Speed Heat P + P P +
OFAN Speed Cool P + + P
OFAN Speed Heat + + P
EEV Cool + + + + +
EEV Heat + + + + +
Deicing + + + P
Base Heater +
Cranck case Heater + +
Indoor load (NLOAD) +
IFAN Speed (Heat) +
Heating Element (Indoor) +
P – Sensor is acting only for protection
+ - Sensor is active part of the control.