Thermo Scientific 61-12C, Operating And Service Manual

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Thermo Fisher Scientific REC 3449 Rev M 3-1
Chapter 3
Operation
Overview
The speed sensor element employs a brushless, pulse generator which
produces a stream of pulses, each pulse representing a unit of belt travel.
The frequency of the pulse stream is proportional to true belt speed. The
pulse output signal is fed to the Integrator/ Totalizer.
Model 61-12 C
The Model 61-12 C supplies the output of the generator directly to the
totalizer for high speed operation (20-200 RPM).
The rotor consists of a 50-slot permanent magnet that is rotated in the
stator. The 61-12 C puts out 50 pulses per revolution; the output
frequency is therefore the product of RPM x .8333. The output signal is a
+5.6 volt pulse. The 61-12 C does not require an external power source to
operate.
Figure 3-1. Method B Installation