1771-LC3B

The Allen-Bradley 1771-LC3B Single Loop Controller Module is a microprocessor-based controller which monitors and directs various application processes. It communicates using the DH-485 serial communication line and features 8 configurational keypads, and LCDs with a 2-line alphanumeric display, a graphics display with 50-segment bar graphs, and status indicators. The controller has an accuracy of 0.1% for analog and frequency inputs. The 1771-LC3B accepts frequency and discrete and analog inputs and it can accommodate a maximum of 4 DC current inputs (4-210mA), 1 thermocouple input, 2 frequency inputs (1 to 9999Hz), and 1 Resistance Temperature Detector input (RTD).

The 1771-LC3B transmits both discrete and analog output signals with 4-20mA at 500 ohms analog signals specifically for control and 1-5V DC (2Kilo ohms) signal for the interface. It also has 2 open collector transistor switches with contact ratings of 50V DC at 250mA. The 1771-LC3B has a 120V AC power requirement at 47-63Hz with 30VA apparent power and has a transmitter power supply rating of 25V DC (nom) with 250 Ohms resistor which power for 2 (4-20mA) transmitters. It has 3bB at 3Hz (with a 5% amplitude signal) frequency response with loop update time of 100ms for normal operation and 200ms in the EXACT mode with output limiting of -2-102%. The 1771-LC3B has 5-50°C (40-120°F) working temperature range, within an ambient humidity range of 5-95% without condensation.