1785-LT3

Product Overview

1785-LT3 is an Allen-Bradley Classic PLC-5 programmable controller designed for reliable industrial automation and process control applications.

Electrical Characteristics

• Backplane Current: 2.5 A

Environmental Conditions

• Operating Temperature: 0° to 60°C (32° to 140°F)

• Storage Temperature: -40° to 85°C (-40° to 185°F)

• Relative Humidity: 5% to 95%, non-condensing

Mechanical Durability

• Vibration (Operating & Non-Operating): 1 g @ 10–500 Hz, 0.012 in peak-to-peak displacement

• Shock (Operating): 30 g peak acceleration for 11 ±1 ms

• Shock (Non-Operating): 50 g peak acceleration for 11 ±1 ms

Timing & Clock Accuracy

• Time-of-Day Clock Variation @ 60°C: ±3 min per month

• Typical Variation @ 20°C: ±20 s per month

• Timing Accuracy: One program scan

Performance

• Typical Discrete I/O Scan: 1 ms per local I/O rack

• Remote I/O Communication: 10 ms per adapter @ 57.6 kbps

I/O Compatibility

• Supported Modules: Bulletin 1771 I/O (8-, 16-, 32-point, and intelligent modules)

• Hardware Addressing:

• 2-slot: Mix of 8-pt modules; 16-pt must be paired; no 32-pt modules

• 1-slot: Mix of 8- or 16-pt modules; 32-pt must be paired

• 1/2-slot: Any mix of 8-, 16-, or 32-pt modules

Communication

• DH+ Network: Up to 3,048 m (10,000 ft)

• DH Connection: Via 1785-KA module

Installation Details

• Mounting Location: Left-most slot of 1771 I/O chassis

• Keying Positions: Between 40–42 and 54–56

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