Technical Instructions
Document No. LV5‐1000
For information on what VSD standardizing is or how to perform standardization, see Section 5.
The standardized speed can be viewed using the following menu path:
Params & Display > VSD Module > Configuration > Speed > StandardizedSp
For a 3600 RPM motor, the standardized speed is typically 3500 +/‐ 100 RPM. If this is the case,
the standardization was successful. If the VSD does not standardize successfully, check the
following:
1. The VSD cannot standardize if the safety loop is open. Check that the safety loop is closed
by making sure there is 120 VAC on terminal X3‐03.1. If there is not, check the limits in the
safety loop and the burner flange to see which limit is open.
2. Ensure that the LMV52 is not in alarm. If so, reset the fault and attempt to standardize
again.
3. Verify the speed wheel is installed on the blower motor correctly and the gap between the
speed sensor and the speed wheel is correct (about 1/16"). Also, use Section 2 to verify
that the wiring from the speed sensor to the LMV52 is correct. The yellow LED on the back
of the speed sensor should blink every time a speed wheel "finger" passes by the nose of
the sensor. If it does not blink, the sensor is wired incorrectly, the sensor is mounted too far
from the speed wheel, or the sensor is defective.
4. Check to ensure that the air damper opens when the standardization is activated.
If this does not happen, set the air actuator to "air influenced" using the following menu
path:
Params & Display > RatioControl > Gas/Oil Settings > AirActuator
5. Check the ramp times on the LMV52 and the VSD.
The ramp times on the VSD must be faster (shorter) than the ramp times on the LMV52.
The LMV52 ramp times can be found using the following menu paths:
Params & Display > RatioControl > Times > OperatRampMod
Params & Display > RatioControl > Times > TimeNoFlame
In general, the VSD ramp times should be set about 5 seconds faster (shorter) than the
LMV52 ramp times.
Section 7
Unsuccessful VSD Standardization
Page 20
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