CHAPTER 7 - APPLICATIONS AND PROGRAMMING
133
7.1.6.7 Hydraulic pump load type
(P202=3)
Starting (P120=2 or P120=3):
1)
Before any setting, carefully read carefully the steps described in
Starting with Pump Control, item 7.1.5;
2)
If the pump control does not meet your requirements our if a
control with better performance is desired, use the torque control;
3)
With a linear torque ramp you can obtain a speed curve very
similar to the S-Curve with quadratic loads, as centrifugal pumps;
4)
Through the load curve you can set the torque 10% to 20% higher
than the load torque for the initial point P121, and 20% to 30%
higher than the load torque for the end point, P122;
5)
Even when the load curve is used, we recommend executing a
setting at the application field. For this, proceed as follows:
5.1) Set P121 to the torque required for the running pump;
5.2) Set P122 to 110% to 130% of the rated motor torque;
5.3) Set P102 initially to lower values, 10s to 15s, then increase this
setting.
7) The main purpose of the two above mentioned cases is maintaining
the pressure ramp as linear as possible, increasing it gradually;
8) As already described in the pump control, the use of a measuring
instrument is required for measuring this pressure and so obtaining
the best setting;
Figure 7.17
– Manometer showing the pressure increase, linear torque
6) If the load has a higher initial torque, could be used the quadratic
torque (P120=3 points);
Figure 7.18
– Manometer showing the pressure increase, quadratic torque
Tn(%)
Start
P121
0
P102
Maximum Time
Torque Control
Enable
Load Torque
Tn Nominal
Speed
P122
Tn(%)
Start
P121
0
P102
Torque Control
Enable
Load Torque
Tn Nominal
Speed
P122
P123
Maximum Time
P124
P120
=3
Torque
Control
P122
P123
P104
0
P124
P120
=2
P102
Torque
Control
P122
P121
P104
0
P126
P125
=1
P102
P121
P126
P125
=1
Phone: 800.894.0412 - Fax: 888.723.4773 - Web: www.clrwtr.com - Email: [email protected]
