Figure 53 - Inverter Wiring; Table 26 - Ycal033 Vfd Low Ambient Option - Condenser Fan Control Operation; Ycal0033 Programming - York YCAL0019 Installation, Operation And Maintenance Manual

FORM 150.67-NM1
ISSUE DATE: 4/28/2017
WHT WHT
TO MICROBOARD (P4) TO MICROBOARD (P4)

FIGURE 53 - INVERTER WIRING

YCAL0033 PROGRAMMING

Condenser fan control type must be programmed un-
der both the OPTIONS and PROGRAM keys when an
VFD is installed on the chiller. Under the OPTIONS
key, FAN CONTROL must be programmed for DIS-
CHARGE PRESSURE CONTROL only. This will as-
sure the condenser fan control is solely by discharge
pressure with no ambient control.
Under the PROGRAM key, the FAN CONTROL ON
PRESSURE should be programmed for 425 PSIG and
the FAN DIFFERENTIAL OFF PRESSURE should be
programmed for 125 PSIG.
TABLE 26 - YCAL033 VFD LOW AMBIENT OPTION – CONDENSER FAN CONTROL OPERATION
FAN STAGE
FAN SPEED
IS A FUNCTION OF
1: DISCHARGE
VFD CONTROL PRESSURE.
(1 FAN WHEN THE LIQUID
VARIABLE LINE SOLENOID IS
SPEED) ENERGIZED. SPEED
INCREASES WITH
PRESSURE
2:
1 FAN VFD
CONTROL 425 PSIG,
2ND FAN BOTH FANS
FULL SPEED WILL BE RUNNING
UNDER FULL SPEED
CONTACTOR
CONTROL
JOHNSON CONTROLS
TB3
TB1 TB1 TB1
TB3 TB3
BLK BLK 152A 152A
TO PANEL 7M TO PANEL 7M
ON OFF
FAN WILL TURN
OFF OR TURN VERY
SLOWLY WHEN
PRESSURE DROPS
BELOW 260 PSIG.
DISCHARGE
PRESSURE
< 260 PSIG
(PRESSURE IS
< FAN CONTROL ON
PRESSURE OF
425 PSIG MINUS FAN
DIFFERENTIAL
PRESSURE OF 125
PSIG = 300 PSIG)
151A 151A
150A 150A
TO FAN #1 (EXISTING HARNESS) TO FAN #1 (EXISTING HARNESS)
Programming as suggested assures the chiller control
points for the second fan in the fan staging sequence
and the inverter control points are matched for opti-
mum control of the fans at reduced ambient tempera-
tures, assuring superheat and oil control is not compro-
mised. When the chiller and VFD fan control points are
programmed properly, the fans will operate as outlined
in Table 26.
CONTACTOR
SYS 1
7M
7M
&
8M
SECTION 8 – UNIT OPERATION
TB2 TB2 TB2
150 150 151 151 152 152
LD11302a
MICRO
FAN #
BOARD
SYS 1 SYS 1
TB7-3 1
TB7-3
& 3
TB7-10
8
195