Kollmorgen M-ST-009-2031, Руководство по установке

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Danaher Motion Operation Information
34 SERVOSTAR
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SBD-Series ST/CT Product Family
The velocity loop monitors the tachometer feedback signal for an over-speed condition and is typically set
to detect speeds in excess of 120% of the motor’s rated speed. Resistor components 1* and 2* set the
reference trip voltage for the over-speed comparator. Considering the absolute tach signal is scaled for
8V=max speed, adjusting the voltage divider to provide a 10-volt trip point allows this circuit to perform
satisfactorily and is established using 1.2k ohms for 2* and 7.2k ohms for 1*. The tachometer must also
be scaled for the over-speed circuit using resistor component 13* calculated as follows:
R13*(in Ohms) = (Tachometer Voltage (V/KRPM) * Rated Speed * 1.2) - 1150
Current Clamps
The current to the motor is clamped according to 3 separate signals as shown in the above figure (Torque
Limit pot, External Current Limit Input, and the Horsepower contour circuit). All clamps work on the
following fundamental scaling: Full speed is 8V and peak drive current is 8V. The clamp circuits work to
limit the current command voltage signal to something less than 8V.
Torque Limit Pot
The torque limit pot allows an adjustment of maximum allowable current. When set clockwise, the pot
allows peak rated current of the drive to the motor. Turning the pot counter-clockwise clamps the
maximum current to less than the drive’s peak rating.
External Current Limit
The external current limit is a user input at connector J2. Tying this input to common activates the
limiting circuit. The limit that is asserted when this input is low is a proportion of the drive’s peak current
limited by the Torque Limit pot and established by the value of component (23) on the comp card.
Component (23) is a resistor whose value is determined from the following chart.
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