Vacon CX, Руководство пользователя

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Vacon Plc
Phone: +358-(0)201 2121 Fax: +358-(0)201 212 205
Service: +358-40-8371 150 E-mail: vacon@vacon.com
Page 42 V V V V Vacon acon acon acon acon Multi-purpose Control Application II Multi-purpose Control Application II
Multi-purpose Control Application II Multi-purpose Control Application II
Multi-purpose Control Application II
7. 9 7. 9 7. 9 7. 9 7. 9 Motor thermal protection, breakpoint frequency Motor thermal protection, breakpoint frequency Motor thermal protection, breakpoint frequency Motor thermal protection, breakpoint frequency Motor thermal protection, breakpoint frequency
The frequency can be set between 10—500 Hz.
This is the breakpoint of thermal current curve. With frequencies above this point
the thermal capacity of the motor is assumed to be constant. Refer to the figure
6-26.
The default value is based on the motor's name plate data, parameter 1
..... 11. It is 35
Hz for a 50 Hz motor and 42 Hz for a 60 Hz motor. More generally it is 70% of the
frequency at field weakening point (parameter 6
..... 3). Changing either parameter 1 .....
11 or 6 ..... 3 will restore this parameter to its default value.
105%
par. 7. 5
Θ
= (I/I
T
)
2
x (1-e
-t/T
)
I/I
T
UMCH7_92
Trip area
Motor temperature
Time
Motor temperature
Time constant T
*)
*)
Changed with motor size and
adjusted with parameter 7. 8
Trip/warning
Motor
current
Parameters 7. 10— 7. 13, Stall protection Parameters 7. 10— 7. 13, Stall protection
Parameters 7. 10— 7. 13, Stall protection Parameters 7. 10— 7. 13, Stall protection
Parameters 7. 10— 7. 13, Stall protection
General
General
General General General
Motor stall protection protects the motor from short time overload situations like a stalled shaft.
The reaction time of stall protection can be set shorter than with motor thermal protection. The
stall state is defined with two parameters, 7.11. Stall Current and 7.13. Stall Frequency. If the
current is higher than the set limit and output frequency is lower than the set limit, the stall state
is true. There is actually no real indication of the shaft rotation. Stall protection is a type of
overcurrent protection.
Figure 6-27 Calculating motor temperature.
7. 10 7. 10
7. 10 7. 10
7. 10 Stall protection Stall protection
Stall protection Stall protection
Stall protection
Operation:
0 = Not in use
1 = Warning
2 = Trip function
Tripping and warning will display the same message code. If tripping is set on, the
drive will stop and activate the fault stage.
Setting the parameter to 0 will deactivate the protection and will reset the stall time
counter to zero.