11-3
CONTROL SYSTEM
SM YAZDCI 1-A.1 GB
11.2.7 Dry
Contacts
Dry contacts are used to interface the system with an external building management system
(BMS).
Night
input. Switches the system to night mode when closed.
During night mode, the outdoor unit 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.
Forced Mode
input. Used to force the operation mode of the system
Alarm
output indicates a failure at the system.
Alarm output will be activated when there in the following ODU Faults/Protections
1 to 7, 11,13 to19, 24 to 26, 28 to 29, 311.
Alarm output will be OFF when the Fault/Protection is cleared.
11.2.8 Temperature
Sensors
CTT – Compressor Top Temperature
OAT – Outdoor Air Temperature
OMT– Outdoor middle coil temperature
OCT – Outdoor Coil (heat exchanger) Temperature
HST – Heat Sink Temperature
RGT11..4 – Indoor Unit 11..4 Returned Gas Temperatures
RLT 11..4 – Indoor Unit 11..4 Returned Liquid Temperatures
11.2.9 Base
Heater
Heating element designed to melt any ice that is accumulated on the outdoor unit base during
low heating operation.
11.3
General Operating Rules
11.3.1 Initialization
Initialization process is the first operation done each time power is up.
The targets of the initialization are:
Addressing of IDU’s
Identification of connected IDU’s
IDU Matching Check
EEV’s homing (reset position)
Restoring Parameters from EEPROM/Jumpers/Dipswitches
