Filter
Top Products
EX2100 User’s Guide GEH-6632 Chapter 4 Terminal Board I/O and Equipment Connections
•
••
•
4-9
Field Current Feedback
The field current is measured across a dc shunt at the SCR bridge. This generates a
nominal 100 mV signal, which is input to a differential amplifier. The output voltage
from the amplifier ranges from –5 V to +5 V. A VCO produces a linear proportional
frequency of 0 to 2 MHz with an accuracy of 1% of full scale reading. These pulses
drive the LED in the optical isolator coupled to the fiber-optic cable.
Field Voltage Feedback
The bridge voltage is measured across the negative terminal of the bridge and the
positive terminal of the current shunt. After scaling the voltage with the jumpered
resistors, the signals are input into a differential amplifier which controls the voltage-
controlled oscillator (VCO). The VCO produces a linear proportional frequency of 0
to 2 MHz with an accuracy of 1% of full-scale reading. The pulses drive the LED in
the optical isolator coupled to the fiber-optic cable.