Digital Solid State Soft Starter 48 - 1250A
3.1.3.b Automatic Reset
If Automatic Reset is necessary, change from Manual Reset to Automatic Reset
by using Function F005. (See Section 5 for details). In this mode, a 3-wire control
circuit will be capable of restart when the TD Series has reset itself after the cool
Two-wire control systems may restart without warning when Auto Reset
is selected. Extreme caution should be exercised. To prevent automatic
restarting with two-wire control systems, use external interlocking to
provide sufficient warning and safety to operators. A Warning Label (such
as the one provided in the packet with this manual) must be placed to be
visible on the starter enclosure and/or the equipment as required by local
MOTOR CONNECTED TO THIS EQUIPMENT MAY
START AUTOMATICALLY WITHOUT WARNING
3.2 NEMA Class Trip Curves
The TD Series Soft Starter provides six NEMA Class trip curve options: 5, 10,
15, 20, 25, and 30. Program the appropriate curve according to the characteristics
of your motor and load.
NEMA Class trip curves are based on a common tripping point of 600% of rated
current. Curves vary by the amount of time before the unit trips. As an example,
a Class 20 curve will trip in 20 seconds at 600%. The factory default setting of
Class 10 will trip in 10 seconds at 600%.
3.2.1 Dual Overload Trip Curves
The TD Series Soft Starter provides two separate Overload Trip Protection Curves,
one for starting and one for running conditions. Programming a higher NEMA
Class overload during start (ramp-up) will eliminate nuisance tripping in higher
inertia or high friction loads.
The starter's At-Speed detection circuit determines when the motor has reached
full speed based on closed loop feedback signals. When the At-Speed condition
is reached, the overload trip curve will shift from the Start to the Run level, as
programmed in Functions F003 and F004. See Section 5 for programming details.
TD - Series
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