Rockwell Automation T6200 Compressor Anti-Surge and Capacity Controller - Manual (Page 15)

Input/Output Circuit Description
2-3
INPUT/OUTPUT CIRCUIT
DESCRIPTION
Each control board in the T6200 Controller incorporates the
µP, memory, communications and I/O
circuitry. Separate I/O modules are not required.
Analog Voltage Inputs
Up to 20 channels in the T6200-C Controller can be configured with field changeable jumpers for
voltage inputs. In reference to Figure 2-1, the input amplifier does not have galvanic isolation but it
appears to have it in most applications because of its high common-mode voltage and its high input
resistance. The 100 volt transient absorbers on each input will allow up to 100 volts dc or 75 volts
ac (rms, sine wave) continuously or up to 104 volts impulse voltage to enter the amplifier. The
amplifier will continue to operate with up to 200 volts on its inputs.
Each input has a separate input amplifier. The output of each of these amplifiers passes to the
analog switch. Only one of these inputs is selected at one time. The selected signal continues to the
programmable gain amplifier (PGA). The microprocessor selects the optimum gain setting for the
PGA. The possible input full scale ranges that can be selected are 0.625, 1.25, 2.5, 5, and 10 volts.
Inputs may be either polarity.
The voltage input configuration can be used as a current input by putting a resistor between the “+”
and “-” input terminals. Use a 250 ohm resistor for a 4 to 20 milliampere loop and a 100 ohm
resistor for a 10 to 50 milliampere loop.