Sutter Instrument SmartShutter Lambda SC, Operation Manual

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LAMBDA SC OPERATION MANUAL – REV. 1.14C (20190606)
the number of steps selected. For a complete opening of 144 steps, the time to open and the
time to close will each be about 38 msec. The time required will be approximately
proportional to the number of steps, or about 2.6 msec per 10 steps.
7.3.3 Repetition Rates and Duty Cycle
Operation does not require over-driving the motor windings, so the motor windings are not
damaged by frequent opening and closing over long time periods. 25 mm (one inch) versions
can usually operate well at up to 20 Hz. 35 mm versions can usually operate well at up to 15
Hz. These shutters may be operated at higher rates up to 40 Hz, but there will normally be
specific frequencies in these higher ranges that will produce errors in motion of the shutter
blade. This is the result of resonances in the mechanical and electrical systems.
If the duty cycle is substantially different from 50%, errors in movement may occur at lower
frequencies. At 40 Hz the cycle time is 25 msec., with 12.5 msec. between open and close
commands. This is close to the absolute minimum time in either the open or closed state. If
you attempt to reduce the time in either state below 12 msec, the controller will not start to
change the shutter state until the 12-msec minimum period is over.