Troubleshooting - Greenheck vari-green Installation, Operation & Maintenance Manual

Operation and Wiring
- Potentiometer Dial and 0-10V Input
Part Numbers Covered in this Section
310359 311731 311377
312359 312360 312361
These motors have both a potentiometer dial on the
motor for speed adjustment AND have the ability to
accept a 0-10 VDC signal for remote speed control.
NOTE: The presence or absence of the 24V power
determines whether the motor uses the dial or the
0-10 VDC signal for speed reference.
There is a 4 second delay between the application of
power and the motor starting.
The motor is pre-wired at the factory and cannot be
changed inside the motor. Connect single-phase power
at the voltage listed on the nameplate. If remote control
is desired, connect the 0-10 VDC and 24V signal for
remote speed control.
Dial on motor – A small screwdriver can be used to
make the speed adjustment. To increase the speed,
rotate the dial clockwise. To decrease the speed, rotate
the dial counter clockwise. There is no need to connect
the control wires.
0-10 VDC signal – The dial on the motor must be
rotated fully clockwise to achieve the full speed range.
If this is not done, the dial will act as a maximum
speed limiter.
From 0-1.9V, the motor will be off, and will operate in
the 2-10V range. 24 VAC/DC power is also required for
operation. The motor will consume 0.7VA at 24 VAC
or 25mA at 24 VDC. A factory mounted transformer is
available to supply this voltage. See Fig. 1
A low voltage wiring harness is needed to supply the
0-10V signal to the motor. This harness is available from
the factory if conversion is necessary.
Type Use with Motor
3-pin 311731, 310359
312359, 311377,
311812, 311388,
9-pin
312360, 312361,
312362, 312619
The 9-pin connector on the motor contains 6 wires.
The red, black and white wires are used for the
external control signal and the other three are used for
factory initialization and programing.
®
311388 311812
312362 312619
18 in. long 36 in. long
384431 384432
384840 384805
NOTE
Factory Mounted Transformer
A factory mounted transformer is available to
supply 24 VDC power to the motor when the
0-10V signal is by others. This transformer has
the capability to power a remote device if desired.
The power available to a remote device is 400mA
at 24 VDC. If the remote device is powered by
a different source, connect the analog output to
the 0-10V and COM terminals of the transformer.
This will pass the signal through to the motor.
WARNING
Do not connect an external 24V transformer to the
control terminal labeled 24V. If the external device
providing the 0-10V signal is powered elsewhere,
this terminal can remain unused.
0-10V Analog input connection
Red
White
Black
* Common is shared between both 24V power
and 0-10V signal.
The impedance of 0-10V circuit is 12KΩ

Troubleshooting

Motor does not operate
1. Check all wiring connections to ensure they are
correct and secure.
2. Verify that all voltages are present at the motor,
including 24V and 0-10 VDC, if applicable.
3. Make sure that the fan wheel will rotate freely and
there are no foreign objects in the wheel. If fan wheel
does not rotate freely, disconnect power from the
motor and adjust the wheel or housing until the
wheel can freely rotate. Apply power and the motor
should restart.
4. If motor has both the dial on the motor and 0-10 VDC
control option, control wiring issues can be tested
by disconnecting the control wires from the motor.
The motor should then operate using the dial on the
motor for speed control.
Motor will not reach maximum speed
1. Make sure dial is rotated full clockwise, if applicable.
2. Make sure motor is receiving 10 VDC, if applicable.
3. There are some motor/fan combinations
where the motor may not reach nameplate
RPM. See Max RPM table on page 10 for the
maximum motor speed for your application.
(Fig. 1)
+ 0-10 VDC
Common*
+24 VAC/DC
Vari-Green Motor 3