Eaton DS7 Manual page 104

4 Operation
4.4 Potentiometer settings
4.4.1.3 t-Stop
100
In the industry, the t-Stop stop ramp is used predominantly for applications
involving pumps, conveyor belts, and belt drives. For example, it can be used
to prevent goods being conveyed from toppling over (e.g., bottles on a
conveyor belt), V-belts from slipping, and water impact caused by valves
being closed from occurring.
With all other applications, the parameter t-Stop can also be set to zero in
order to prevent any unnecessary temperature rise in the motor.
A soft stop ramp has the same temperature characteristics as a start. It also
therefore causes the heating of the soft starter and motor, and must be
taken into account when determining the starting frequency. The stop ramp
terminates at a set value of U-Start. A correct setting will cause the minimum
torque to be generated at which the motor still turns. At lower voltages
(torques), the machine remains at standstill due to losses or friction.
The stop ramp is activated when the start command is turned off (low signal
on control signal terminal +A1). The drive then moves with the set stop time
(t-Stop) to the value of the start voltage (U-Start). When this is reached, the
soft starter switches off the output. If the motor still is still turning, it will
perform an uncontrolled stop from this point. The soft stop time is default set
to 0 s, in other words the motor performs an uncontrolled stop.
①
+A1 (Start)
RUN
U
out
U-Start
n
Motor
Figure 72: Operation with ① and without ② soft stop
a With stop ramp (+A1 = OFF, t-Stop > 0)
b Without stop ramp (+A1 0 OFF, t-Stop = 0 s) or via control signal terminal EN
(in the case of sizes 3 and 4) or via SmartWire-DT with t-Stop = 0
DS7 Soft starter 09/16 MN03901001Z-EN www.eaton.com
+A1 (Start)
t-Stop
n
②
RUN
U
out
Motor