JOHNSON CONTROLS
174
FORM 150.67-NM2
ISSUE DATE: 01/31/2019
SECTION 8 – UNIT OPERATION
TB3
TB1
TB2
TO PANEL 10M TO FAN #2 (EXISTING HARNES S)TO MICROBOARD (P7)
251250
252
250A
251A252A
WHT
BLK
TB3
TB1
TB2
TO PANEL 10M TO FAN #2 (EXISTING HARNES S)TO MICROBOARD (P7)
251
250
252
250A
251A252A
WHT
BLK
TB3
TB1
TB2
TO PANEL 7M TO FAN #1 (EXISTING HARNESS)
TO MICROBOARD (P4)
151
150
152
150A
151A
152A
WHT
BLK
TB3
TB1
TB2
TB3
TB1
TB2
TO PANEL 7M TO FAN #1 (EXISTING HARNESS)
TO MICROBOARD (P4)
151
150
152
150A
151A
152A
WHT
BLK
FIGURE 58 - INVERTER WIRING
LD11302
TABLE 28 - YCAL0043-0066 VFD LOW AMBIENT OPTION – CONDENSER FAN CONTROL OPERATION
FAN STAGE ON OFF
CONTACTOR MICROBOARD FAN #
SYS 1 SYS 2 SYS 1 SYS 2 SYS 1 SYS 2
1:
VFD Control
(1 Fan
Variable Speed)
Fan Speed
Is A Function Of
Discharge
Pressure.
When The Liquid
Line Solenoid Is
Energized, Speed
Increases With
Pressure
FAN Will Turn
Off or Turn Very
Slowly When Pres-
sure Drops Below
260 PSIG.
7M 10M TB7-3 TB10-9 1 2
2:
1 Fan VFD Con-
trol
2nd Fan Full
Speed Under
Contactor Control
425 PSIG, Both
Fans Will Be Run-
ning Full Speed
Discharge
Pressure
< 260 PSIG (Pres-
sure Is
< Fan Control ON
Pressure of
425 PSIG Minus
Fan Differential
Pressure of 125
PSIG = 300 PSIG)
7M
&
8M
10M
&
11M
TB7-3
and
TB7-10
TB10-9
and
TB10-
10
1
&
3
2
&
4