Allen Bradley1771-IBDDC Input Module, 16 Point, 10-30 V DC Sink, 1771 I/O Chassis

Product Description

What this part is

Allen-Bradley 1771-IBD discrete input module. Product Type: high-density 10 to 30 V DC digital input module for the 1771 I/O platform. Points: 16. Input Voltage: 10 to 30 V DC. Input Configuration: sink. Backplane Current: 130 mA at 5 V DC. Mounting Type: 1771 I/O chassis, single slot. Unit Quantity: 1 Pc.

Decoding the designation

1771 — the Allen-Bradley 1771 I/O platform, the rack-based I/O family served by PLC-2, PLC-3 and PLC-5 processors.

IB — the 10 to 30 V DC input group within that platform.

D — the double-density execution, giving 16 points in one slot where the plain 1771-IB gives 8.

Electrical data

Points: 16. Input Voltage: 10 to 30 V DC. Minimum On-State Voltage: 10 V DC. Maximum Off-State Voltage: 5 V DC. Input Current: 4.5 mA minimum at 10 V DC, 15 mA at 30 V DC. Minimum Off-State Current: 2.0 mA at 5 V DC. Backplane Current: 130 mA at 5 V DC, +5 percent. Power Dissipation: 7.3 W maximum, 1.0 W minimum. Thermal Dissipation: 24.7 BTU/hr maximum, 3.4 BTU/hr minimum.

Signal Delay: 1 ms off-to-on; 1 ms or 6 ms on-to-off, selectable.

What these specs mean in practice

Signal Delay: 1 ms off-to-on. That is fast for a discrete input card and it is what suits the module to counting, position sensing and other work where a 15 ms filtered input would blur the edge.

Selectable Off Delay: 1 ms or 6 ms. The 6 ms setting adds noise immunity on a long or electrically busy field run; the 1 ms setting keeps the response tight where the signal source is clean.

Points: 16. Double density doubles the field devices a chassis slot carries, which is the whole reason to fit an IBD over an IB where rack space is the constraint.

Input Voltage: 10 to 30 V DC. The band covers 12 V and 24 V control circuits on the same catalogue number, with a 5 V DC maximum off-state threshold giving clear separation between a true off and a true on.

Backplane Current: 130 mA at 5 V DC. That is the figure that goes into the chassis power budget when a 1771-P series supply is sized against a full rack.

Mounting data

Mounting Type: single slot. Chassis: B-series 1771 I/O chassis, including the 1771-A1B, 1771-A2B, 1771-A3B, 1771-A3B1 and 1771-A4B. Terminations: removable field wiring arm. Signal Type: discrete on/off.

Quantity and configuration

Unit Quantity: 1 Pc. One input module.

Interchange guidance

Manufacturer Status: discontinued. Part Number: 1771-IBD. MPN Variants: 1771IBD, 1771 IBD, 1771-IBD-B. The 1771-IB is the 8-point module on the same voltage and the 1771-IBN the 32-point, so those change the point count and the chassis power budget. The 1771-IV is the 12 to 24 V DC driver logic module, which differs in field wiring polarity and in filtering.