Wiring diagrams, Use of variable frequency drives – COOK CPL User Manual
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Wiring Diagrams
7
1
6
7 8 9
4 5 6
1 2
3
Low Voltage
208/230 Volts
High Voltage
460 Volts
8
2
4
9
3
5
L1
L3
L2
L1
L3
L2
3 Phase, 9 Lead Motor
Delta-Connection
4 5 6
1
7
2
8
3
9
L1 L2 L3
4 5 6
7 8 9
1 2
3
L1 L2 L3
Low Voltage
208/230 Volts
High Voltage
460 Volts
3 Phase, 9 Lead Motor
Y-Connection
Fan
Motor
Damper
Motor*
Second
Damper
Motor
Transformer**
Transformer**
L3
L2
L1
Motor
1
2
3
4
5
6
Together
High Speed
Line
L1
L2
L3
1
2
3
4
5
6
Open
Low Speed
Line
L1
L2
L3
Motor
When ground is required, attach to ground A or B with no. 6 thread forming
screw. To reverse, interchange T-1 and T-4.
Single Speed, Single Phase Motor
To reverse, interchange any 2 line leads.
When ground required, attach to ground A or B with No. 6 thread forming
screw. To reverse, interchange T-1 and T-4 leads.
2 Speed, 2 Winding, Single Phase Motor
2 Speed, 1 Winding, 3 Phase Motor
To reverse, interchange any 2 line leads. Motors require magnetic control.
Single Speed, Single Phase, Dual Voltage
2 Speed, 2 Winding, 3 Phase
When ground required, attach to ground A or B with No. 6 thread forming
screw. To reverse, interchange T-5 and J-10 leads.
To reverse: High Speed-interchange leads T
11
and T
12
.
Low Speed-interchange leads T
1
and T
2
. Both Speeds-interchange any 2
line leads.
Typical Damper Motor Schematic
For 3 phase, damper motor voltage should be the same between L
1
and
L
2
. For single phase application, disregard L
3
. *Damper motors may be
available in 115, 230 and 460 volt models. The damper motor nameplate
voltage should be verified prior to connection. **A transformer may be pro-
vided in some installations to correct the damper motor voltage to the
specified voltage.
T-1
T-4
Ground B
L2
L1
Ground A
Line
Ground A
Ground B
T-1
T-4
Low Speed
High Speed
L1
L2
Line
Ground B
J-10
T-5
Ground A
Link A
Link B
Low Voltage
Line
L 2
L 1
Ground A
Link A & B
L1
L 2
Line
Ground B
T-5
J-10
Wiring Diagrams
Wiring -
Line reactors may be required to reduce over-voltage
spikes in the motors. The motor manufacturer should be
consulted for recommended line impedence and usage of
line reactors or filters, if the lead length between the VFD
and the motor exceeds 10 feet (3m).
Fan -
It is the responsibility of the installing body to perform
coast-down tests and identify any resonant frequencies
after the equipment is fully installed. These resonant fre-
quencies are to be removed from the operating range of
the fan by using the “skip frequency” function in the VFD
programming. Failure to remove resonant frequencies
from the operating range will decrease the operating life of
the fan and void the warranty.
connection with the terminal box at the end of the
motor. To remove motor, remove bolts securing motor
base to power assembly. Do not remove motor mounting
bolts.
Use of Variable Frequency Drives
Motors -
Motors that are to be operated using a Variable Fre-
quency Drive (VFD) must be VFD compatible. At a mini-
mum, this must be a Premium Efficiency motor with
Class F insulation. Motors that are not supplied by Loren
Cook Company should have the recommendation of the
motor manufacturer for use with a VFD.
Grounding -
The fan frame, motor and VFD must be connected to
a common earth ground to prevent transient voltages
from damaging rotating elements.