Air/ Fan balance for ECM controlled direct drive units

Use guide for proper air flow, RPM and AMP draw stabilization

1. Command high speed on.

Find ECM board in the control box (Blue display board)

1. Find H1 setting on the sticker
2. Verify H1 RPM is being met, if so no other checks are needed.
3. Example: High speed setting is 1000 RPM, MTR1 scrolls to “MTR1 999, scrolls around again to 1000, scrolls around again to 998, scrolls around again to 999”.

NOTE: ECM board tries to maintain RPM setting to plus or minus 2%

If high speed RPM is not being met:

1. Example: High speed setting is 1000, MTR1 scrolls to “MTR1 950, MTR1 956, MTR1 961, MTR1 959”.
2. Record MTR 1 actual RPM value as the ECM board displays status (scrolling value).
3. Turn EHPT off
4. Calculate new high speed value. In this example set new MTR1 value for 940. (Roughly 2% less than your highest RPM reading).
5. Change H1 and any other high speed RPM settings to this new value. (Possible values to change: H1, E1M1, E2M1, AHM1).

NOTE: E1M1 and E2M1 values will require EHPT turned off.

After fan is balanced:

1. You will be able to verify airflow by the fan curves located in the catalog.
2. You will lower and stabilize the AMP draw of the motor. NOTE: clamp on meters can vary widely. Use “In series” AMP measurement for more accurate results.
3. You will feel confident that the motor and fan are set to maximize airflow and efficiency.