Model 60-12F - Thermo Scientific 60-12 Operating And Service Manual

Figure 3-2
60-12C Output
Voltage
3.3

Model 60-12F

Speed sensor Model 60-12F is designed for use in low speed systems (3 to 30
RPM). The 60-12F outputs 200 pulses per revolution, and requires and external
power source of 15 to 30 VDC to operate. It contains a two-phase servo generator.
The rotor is a 50-slot permanent magnet that is rotated in the stators. This results in
two AC signals that are out of phase with each other. The output frequency is
determined by the follows: RPM x 3.33 = Hz. The output signal is approximately
equal to the supplied voltage at terminal 17. Operation is as follows.
1. Referring to Figure 3-4, the two AC signals are applied to R-1 and R-5 while the
2. The exclusive or gate that these two outputs feed into merely serves to combine
3. Due to the sensing of the signal level changes of the two phase generator, the
12
common is connected to 2-2, pin 1.Z-2, pin 1 supplies a center reference voltage
for Z-2 pins 9 and 13. As the voltage signal from the generator moves Z-2, pins
10 and 12 above and below the center reference voltage the outputs of Z-2, pins
8 and 14 switch from one state to the other. They are maintained in these states
by the action of the two feed back resistors, R-4 and R-8.
them. The portion of Z-2 connected to pins 1 and 2 of Z-1 serves to provide
some integration that will eliminate most signal jitter caused by vibration.
output of this model is increased/ RPM x 3.333 = Hz, or 200 pulses per
revolution.
REC 3016 Rev M