Beijer Electronics BFI-H2 V1.12 - Manual (Page 45)

User Guide Revision 1.12
45
The execution time for both the sleep and wake boost functions (P6-11 and P6-12) include the time taken to accelerate to the boost speed (P2-
07 and P2-08) but not the time to accelerate or decelerate once the boost function ends. This is shown in the timing diagrams.
When boost on sleep in activated the drive will automatically run the boost on sleep function whenever the drive is stopped / disabled. When
boost on wake is activated the boost on wake function is automatically run whenever the drive is started / enabled.
8.3. Application Example
Using the drive to control pressure in a simple pump system
The diagram for the pump system is shown below.
The drive is to maintain pressure at the output of the pump to the set-point value and to maintain that set-point as different output values are
opened and closed.
Firstly the Pressure sensor is connected to the drive second analog input (terminal 10). The following parameter changes are made to
configure the HVAC unit to accept the feedback signal from the sensor.
 P3-10 = 0 (default): Sets the PID feedback source as analog input 2

P2-33 = t 4-20: Sets analog input 2 to accept a 4-20mA reference and to trip on loss of signal.
Next the set-point signal from the control system is connected to drive analog input 1 (terminal 6). The following parameter changes are made
to configure the HVAC unit to accept the set-point signal from the control system.

P3-05 = 1: Sets the PID set-point source as analog input 1
 P2-30 = U 0-10 (default): Sets analog input 1 to accept a 0-10V reference
Lastly active PID control on the drive, configure and tune the PID settings.

Set P1-12 = 3: Sets the drive control to PID mode (enables the PID controller)
 Set P3-04 = 0 (default): Select Direct control mode. As the feedback signal falls (pressure drops), the speed of the pump is increases
and vice versa.
 Starting from the default values suitable value for the P-gain, I-gain and D-gain are adjusted to give best performance in P3-01, P3-02
and P3-03 respectively.
Adding Sleep and Wake thresholds to the pump system
With the pump system shown above the design of the pump is such that it is performing very little useful work when run below 20Hz. The
drive is required to shut off the pump if pump speed falls below 20Hz for longer than 1 minute. The pump must start up again when the
feedback error increases above 10%. The following settings are made to the drive.
 P3-14 = 20Hz: Standby level. Standby function is activated when the drive goes below 20HZ for longer than the time set in P2-27

P2-27 = 60s: Standby timer. Standby function is activated when the drive goes below P3-14 for longer than 60 seconds.

P3-13 = 10%: Drive will wake when PID error increases beyond 10%.