The Allen-Bradley 1771-IA2 module reliably connects field devices to your PLC-5 control system. This module works specifically with AC/DC proximity switches, though it also handles pushbuttons and limit switches effectively. It converts high-voltage input signals into logic-level signals that the processor reads. Consequently, it updates the corresponding bits in the PLC data table in real time.
Additionally, this module includes the 1771-WA wiring arm. This removable terminal block allows you to pre-wire field devices before installation. You can quickly disconnect the arm during module replacement without touching the field wiring. Therefore, you minimize downtime and significantly reduce installation errors.
The Allen-Bradley 1771-IA2 offers eight discrete input channels for both AC and DC power sources. The AC operating voltage spans 87 to 138 Volts, while the DC operating voltage ranges from 97 to 138 Volts. This voltage flexibility makes the module a versatile choice for many industrial environments.
Moreover, the module features clearly defined signal delay characteristics. For AC inputs, the typical ON and OFF signal delay is 24 milliseconds (±10 ms). For DC inputs, the ON delay is faster at 10 milliseconds (±4 ms), and the OFF delay is 20 milliseconds (±9 ms). The module draws a backplane current of only 75 mA. Additionally, it has a maximum off-state current of 2.8 mA, which prevents false triggering from residual voltage.
Physically, the 1771-IA2 measures 3.5 x 6.5 x 2.0 inches (89 x 165 x 51 mm). It occupies a single slot in any 1771 series I/O chassis, such as the 1771-A1B through 1771-A4B. This compact, space-saving design helps you maximize I/O density in your control cabinet.
Furthermore, the front panel includes eight orange status LEDs. These indicators give you immediate visual confirmation of each input's ON/OFF condition. This feature simplifies troubleshooting and speeds up system diagnostics significantly. The module also incorporates optoelectrical isolation and built-in input filtering. These features protect the system from electrical transients and reduce noise. Therefore, the module delivers stable operation even in electrically harsh industrial settings.
Installing the 1771-IA2 requires careful attention to slot assignment and keying. First, insert the module into any empty slot in the PLC-5 chassis. Ensure the backplane connectors align correctly. Next, verify that the power supply has enough capacity for the module's 75 mA load.
Second, proper keying is vital for safety. You must install the provided keying bands between pins 10 and 12 on the upper connector. You also need to place them between pins 4 and 6 on the lower connector. This physical keying prevents the insertion of incompatible modules. As a result, it protects both the module and the backplane from potential damage.
Your shipment for the Allen-Bradley 1771-IA2 module includes the following:
(1) Allen-Bradley 1771-IA2 Digital Input Module
(1) Pre-installed 1771-WA Field Wiring Arm
(1) Product Installation and User Guide
All components come securely packaged for safe transit. We dispatch all orders using trusted carriers such as FedEx, UPS, and DHL.
1. What is the difference between the 1771-IA and the 1771-IA2?
Both modules offer 8 channels with 120V AC/DC operation. However, the 1771-IA2 works specifically with AC/DC proximity switches and is a Series A module. The standard 1771-IA is a Series C module for broader general-purpose use.
2. Can this module operate with a 230V AC power supply?
No, the 1771-IA2 only supports 120V AC/DC operation. The maximum AC input voltage is 138 Volts. Connecting it to 230V will cause permanent damage to the circuitry.
3. What role does the 1771-WA wiring arm serve?
The 1771-WA is a removable wiring arm that terminates all field signal wires. It lets you detach the wiring from the module without disturbing the field connections. This design makes module replacement fast and error-free.
4. How can I tell which input channel is active?
Each of the eight input channels has a dedicated orange status LED on the front panel. When a valid signal appears on a channel, its corresponding LED turns on, giving you instant visual feedback.
5. What keying bands does this module require for installation?
To ensure correct slot placement, install keying bands between pins 10 and 12 on the upper connector. Additionally, place them between pins 4 and 6 on the lower connector of the chassis backplane.
| Brand Name | |
| Model No. | 1771-IA2 |
| Product Type | Digital Input Module |
| hasMerchantReturnPolicy | Adjust according to reality |
| Shippingdetails | Adjust according to reality |
