McQuay MDS030AR Applications Manual page 48

Design & installation Guide For McQuay MDS Multi System
-48-
Model MDS260/280/300BR(Slave Unit)
380V/3N~/50Hz
R S T
KM1 KM2 KM3
OL1 OL2 OL3
18 19 20
T2 T2
T2
T1 T3 T1 T3 T1 T3
M M M
~ ~ ~
Shaft heater Shaft heater
Shaft heater
compressor 1 compressor 2 compressor 3
Description of components and parts :
Symbol Description Symbol
DB3A Phase-loss/reverse protector FU Fuse
4WV Four-way valve EXV1 System electronic expansion valve
KM Contactor EXV4 Over cooling electronic expansion valve 4
HP High-pressure switch OL Overload protector
LPT Low -pressure sensor TR Transformer
HPT High-pressure sensor
FU L
T 71
S DB3A
81
R N
KM4 KM5
OL4 OL5
21 22 23 24 25 26
M
~
Fan motor
Overload protection settings :
Description
OL1 OL2 OL3
14.0 14.0 14.0
DIP switch settings :
Model S1.1 S1.2
MDS260BR OFF OFF
MDS280BR OFF OFF
OFF OFF
MDS300BR
MDS320BR OFF OFF
LOW-I
HI-1 TH7 TH6 TH5
TR
V1+
BLACK
V1-
V2+
WHITE
V2-
FIX3-OL
OL2 12
FIX2-OL
13
OL1
MDS-P
FIX1-OL
14
OL3
DIG-OL
LP
L1 HP 15 OL4 OL5 17
16
HP
N
L
J18
J1
OL4 OL5
Notes:
3.3A 1.8A
1: -----------Field wiring
2: --------------
S2.1 S2.2 S2.3 S3.1 S3.2 S3.3 S3.4
3: S1.3~S1.8 set the number of indoor units. S2.1 sets the
OFF OFF ON ON OFF OFF OFF
OFF OFF ON ON OFF OFF ON
OFF OFF ON ON
OFF ON OFF
OFF OFF ON ON OFF ON ON
LPT HPT
1 2 3 1 2 3
TH3 TH12 TH11 TH10TH9 TH8 TH4 TH2 TH1 LOW-U
HI-U
MDS-M
Connecting the indoor unit
32
33 Connecting the master unit
S1 S2 S3
EXV1 EXV4
7
2 4 8 10 11
KM5 EXV1 EXV4
KM4
3 5
KM5 KM4 4WV KM2 KM1 KM3
Factory wiring
unit as a master/slave. For details of S2.4~S2.8.