Delta Electronics VFD-EL manual 10.27, Reserved, 10.33

Chapter 4 Parameters

Example: suppose that the set point of constant pressure control of a pump is 4kg, Pr.10.22 is set to 5%, Pr.10.23 is set to 15 seconds, Pr.10.24 is set to 25%, Pr.10.25 is set to 3% and Pr.10.26 is set to 0.5 seconds. It means that offset is 0.2kg (4kgX5%=0.2kg), i.e. when feedback value is higher than 3.8kg for a time exceeding 15 seconds, the AC motor drive will decelerate to stop (this deceleration time will act according to Pr.01.12). When the feedback value is less than 3.8kg, the AC motor drive will start to run.

Status 1: Suppose that the AC motor drive is in the constant pressure status and the feedback change value is less than 0.12kg within 0.5 seconds. The AC motor drive won’t run until the feedback value is decreased by this proportion to the value less than 3kg.

Status 2: When the AC motor drive is in constant pressure, it won’t run until the feedback change value is less than 3.88kg (4-4kgX3%=3.88kg) for a time exceeding 0.5 seconds.

10.27

Reserved

10.33

4-108 Revision August 2008, 2ELE, V1.02