Electra WNG 50 DCI Service Manual page 54

11.30 Compressor Frequency Control
Outdoor Unit NLOAD setting
11.30.1
The MSMP controller gets the NLOAD from each of the indoor units, and sends a
combined NLOAD to the outdoor unit control. The combined NLOAD is a
weighted average of the indoor units NLOAD.
The weight of the indoor units as a function of their nominal capacity:
Indoor Unit Capacity [kW] (kBtu/hr)
2.5 (9000)
3.5 (12000)
5.0 (18000)
7.2 (24000)
11.31 EEV (electronic Expansion valve) Control
EEV opening is defined as EEV = EEV
x
EEV
OL
frequency, operation mode, unit model and capacity.
x
EEV
CV
mode on the relevant indoor unit super heat and compressor temperature.
x
During the first 10 minutes of compressor operation EEV
11.32 System Mode Setting and Reversing Valve (RV) Control
The first indoor unit that is causing the system to be turned ON sets the system
mode.
Indoor Units Operation when Indoor Unit Mode is Different than
11.32.1
Outdoor Unit Mode
x
Open louvers according to user selection.
x
Indoor fan is forced to OFF.
11.33 Dry Contacts Control
Dry Contact
STBY
Night
A dry contact output for Alarm will be shorted when any failure exists in the system
Service Manual - WNG 50_60_80 DCI
is the initial EEV opening as a function of the compressor
is a correction value for the EEV opening that is based in cooling
Contact = Open
No Limit
No Limit
Revision Y05-02
CONTENT
Capacity Code
+ EEV
OL CV
Contact = Short
System is Forced to STBY
Outdoor fan speed reduced to low in cooling mode
CONTROL SYSTEM
1
1.5
2
3
.
= 0
CV
.
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