Tuning – Davey Speedman Dual Pump Variable Speed Pump Control System User Manual
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Minimum Frequency or Shutoff Head
The minimum frequency is the lowest setting at which a pump will begin to contribute to the system pressure.
This value is expressed as a percentage.
This is the minimum frequency at which the Speedman determines that a pump is to be stopped as at this
speed it is not contributing flow.
There are two ways to setup the Minimum Frequency,
“Fixed” or “Calculated”; this is selected by editing the “Min Freq Mode” option in the Configuration Menu.
Fixed - a fixed valve is selected for all set points.
The pump minimum frequency (Hz) can be found in your pump’s data sheet.
Divide this minimum value by the maximum speed of the pump (Hz) and
multiply the result 100 to get minimum frequency (%). Enter this value
Calculated - The Shutoff Head of the pump is entered and the Min Frequency
is then calculated based on the Shutoff Head value and the current set point.
The actual calculated minimum pump speed is shown on the right hand side of
the display.
Response Rate (Proportional)
The response rate is a figure used to set the speed of reaction of the system.
It is expressed as a percentage ranging from 0.1 - 100.0.
0.1 is the slowest response and 100.0 the fastest.
The current pressure reading is also displayed to assist while tuning – Shown above as “nn”
Acceleration
The acceleration of the VSD can be limited by this figure. It is designed to
Brake the PID control. It is used in cases where the Acceleration needs to be
dampened. The figure is input in %/second.
High Pressure Restarts
This setting allows the operator to set the number of times that the system can
shutdown and automatically restart after a High Pressure Shutdown.
The range is from Off to 1-250.
”Off” - the system shuts down after the High Pressure delay timer trips (default).
“Automatic restart” – (per hr) The Speedman will allow “X” restarts in an hour commencing from the first
High Pressure Fault. A message “New Fault” appears on the main screen on each restart and is logged in the
fault log.
Min Frequency
XX.X %
Shutoff Head
XXXX (XX.X%)
Response Rate
XXX.X % (nn)
Acceleration
XXX %/Sec
HiPress Restarts
XXX
TUNING
Minimum Frequency
%
0.0 - 100.0
45.0
Shutoff Head
Unitless
0 - 9999
1924
Response Rate
%
0.1 - 100.0
2.0
Acceleration
%/second
1 - 100
20
High Press Restarts
number
Off, 1 - 250
Off
Standby Boost
% of Setpoint
10 - 250
20
Standby Flow Min
/Sec
0 - 9999
200
Error Correction (I
seconds
Off, 0.1 - 100.0
3.0
Overshoot Elimination (D
%
Off, 0.1 - 50.00
15.0
RP(P) EC(I) OE(D
number
-1000, 1000
display