Trane VUV Installation, Operation And Maintenance Manual page 63

Although the VelociTach™ motor control board ships with
settings that will work with most 0–10 Vdc outputs, calibration
should be performed to maximize response range and
controller authority. Typically, the only settings needed for the
VSP inputs are calibration of the signal to ensure that the
system obeys the following rules:
• The minimum output from the field supplied controller is
met with a positive fan response. That is, we do not want
vflr
the setting on the motor control board to be higher
than the minimum output of the field supplied controller, as
the motor control board will "ignore" a portion of the usable
range of the customer fan variable speed output.
• The minimum output from the field supplied controller is not
significantly greater than the floor setting
minimum output of the controller is significantly greater
than the floor setting, the first point that the motor will turn
AlM1
on will be above the
of motor control will not be fully utilized in this case, as the
motor will never reach the low speed motor analogue input
scaling value for Motor 1 and Motor 2 (
• The maximum output of the controller needs to be 10V, or
if lower, needs to be compensated using the analog input
Aisc
scaling value, to normalize the operational range.
As a default, the scaling value is set to 1.00 (so a voltage
of 5V will be graded as 5V); however, to compensate for
long runs or lower max voltages (i.e., lower than 10.00), the
scaling value can be increased accordingly to maximize
operational range.
For example, if the voltage is only reaching a value of 9.0V
at the adapter boards, then the
1.111
set to (10/9=) . If left un-calibrated, the unit will
never attain maximum speeds, defined as
AhM2
.
• The motor control board can accept slightly over-biased
inputs up to 12 Vdc, and the
to a value less than 1.0 to compensate.
VSP Setup Examples
Vflr
Figure 74. Example 1:
too high
UV-SVX005G-EN
vflr
floor. If the
AlM2
and value. The full range
AlM1 AlM2
and
Aisc
parameter should be
AhM1
and
Aisc
parameter can be set
AiSc
set too high and
Figure 75. Example 2:
correctly
Figure 76. Example 3:
correctly
)
Potentiometer/Rheostat For VSP
Hazardous Voltage w/Capacitors!
Failure to disconnect power and discharge capacitors
set
before servicing could result in death or serious
injury.Disconnect all electric power, including remote
disconnects and discharge all motor start/run
capacitors before servicing. Follow proper lockout/
tagout procedures to ensure the power cannot be
inadvertently energized. Verify with a CAT III or IV
voltmeter rated per NFPA 70E that all capacitors have
discharged.
ECM Overview and Setup
Vflr AiSc
set too high but
Vflr AiSc
set correctly and
WARNING
set
set
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