Procedure
- In the Setup/Progress tab of the Box Flow Test screen, click Read Results.
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Click the Results tab.
Notes:
- If the test is still in progress, the State column displays Test in Progress. Wait until the test completes and read the results again.
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You can also read the results from the previous time the box flow test was performed. Click Read Results before performing the test to view the results of the last performed box flow test.
If there are errors, the error appears in the State column and the result summary appears in the Results Summary column.
The following are the possible results:-
Large dP Offset: Set if the absolute value of the Percent dP Offset is greater than or equal to the dP Offset Tolerance. This indicates that an auto calibration was performed when the damper was not fully closed. This is often a symptom of a stuck or reversed actuator. This error is evaluated on input change while the test state is Test in Progress or No Test Data. The error is reset when a test begins and the absolute value of the current Percent dP Offset input is less than the dP Offset Tolerance.
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Flow Not Reliable: Set if the Flow input Reliability is not reliable. This error is evaluated on input change while the test state is Test in Progress or No Test Data. The error is reset when a test begins and the Flow is currently reliable. This error indicates one or more of the Flow readings is not reliable.
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Damper Command Not Responding: Set if the Damper Percent Cmd input did not reach the Step Position (within 1%) for one or more of the test steps. This indicates the application is being controlled by higher precedence logic.
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Poor Flow Response: Set if (Max Flow - Min Flow) <= (Rated Box Flow * Flow Tolerance / 100). The Min Flow and Max Flow refer to the minimum and maximum of the recorded flow values.
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Insufficient Flow: Set if (Max Flow) < Rated Box Flow * (100 - Flow Tolerance) / 100.
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Excessive Flow: Set if (Max Flow) > 1.5 * Rated Box Flow.
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Non-Increasing Flow: Check all steps (other than the starting position) against previous step to verify flow is moving in direction expected. Considered an error if moving opposite expected direction (by more than half the tolerance) for any of the steps or if the flows at the fully open or closed positions are not within the tolerance of the max or min flows, respectively.
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Excessive Hysteresis: Evaluated only if Check Hysteresis is True. For all positions that have a pair of flow values (all steps except the end stop opposite the starting position), set error if flows differ by more than the tolerance.