Allen-Bradley 1734-IA4 120V AC Input Module

1734-IA4 Product Introduction

The Allen-Bradley 1734-IA4 discrete input module offers a practical solution for monitoring 120V AC field devices within the POINT I/O architecture. This module provides four (4) non-isolated sinking input channels, making it suitable for applications that require multiple AC signal inputs in a compact footprint. Specifically, the 1734-IA4 connects directly to sensors, pushbuttons, and selector switches that operate at standard AC line voltages. Its sinking wiring configuration ensures compatibility with common field devices. Meanwhile, the module's small size allows installation in tight spaces, and the individual LED indicators on each channel give operators instant visual confirmation of input status. Additionally, the 1734-IA4 integrates seamlessly into networks such as EtherNet/IP, DeviceNet, and ControlNet through compatible POINT I/O adapters.

Technical Specifications

Understanding the electrical parameters of the 1734-IA4 is essential for proper system design. First, this module operates at a nominal input voltage of 120 Volts AC, with a full operating range from 85 to 132 Volts AC at 47 to 63 Hertz. The module requires a minimum On-state voltage of 65 VAC and accepts up to 132 VAC maximum. Its On-state current ranges from 4.0 mA at 65V AC to 8.5 mA at 132V AC. Conversely, the maximum Off-state voltage is 43 VAC, with a corresponding Off-state current of 2.7 mA. Moreover, the 1734-IA4 draws a backplane current of 75 mA at 5V DC, which aligns with the standard POINTBus power budget. The nominal input impedance is 10.6 kiloohms, ensuring proper loading for most AC sensors.

Furthermore, the Allen-Bradley 1734-IA4 provides robust isolation between the field side and the system. The continuous isolation voltage rating reaches 240 Volts AC, and the module passes a dielectric test of 3250 Volts DC for 60 seconds. This isolation protects the control system from voltage transients and ground loops. Power dissipation is rated at 0.50 W at 132V AC, while thermal dissipation measures approximately 1.71 BTU/hour. These efficient thermal characteristics help maintain lower temperatures inside control cabinets, contributing to overall system longevity.

Mechanical and Mounting Requirements

The 1734-IA4 module offers compact dimensions that facilitate flexible installation. Its physical size measures 56.0 x 12.0 x 75.5 millimeters (2.21 x 0.47 x 2.97 inches), and it weighs only 30.9 grams (1.09 ounces). This lightweight design minimizes stress on mounting hardware and DIN rails. Importantly, the 1734-IA4 requires a compatible terminal base for proper operation. The module mounts onto any of the following bases: 1734-TB, 1734-TBS, 1734-TOP, or 1734-TOPS. These bases provide the physical connection points for field wiring and the backplane interface. Additionally, the module features an open-style enclosure with no specific IP rating, so it should be installed within a protected control panel. The compact form factor allows mounting in either horizontal or vertical orientation, giving engineers flexibility during panel layout design.

Installation Guidelines

Proper installation of the Allen-Bradley 1734-IA4 ensures reliable and safe operation. Begin by attaching the chosen terminal base (1734-TB, 1734-TBS, 1734-TOP, or 1734-TOPS) to a standard DIN rail. Next, snap the 1734-IA4 module firmly onto the base until it locks into place. Wire the external AC power supply to the terminal base, observing the correct connections for the 85-132 VAC supply source. For the input channels, connect field devices according to the sinking wiring configuration. Each input channel accepts one AC signal wire, with the common return shared among all four channels. After completing all wiring, set the key switch to the appropriate position for addressing. Then, apply power and verify that the module status LED turns green. Finally, test each input channel by energizing the connected field device and confirming that the corresponding I/O status LED illuminates. Always follow local electrical safety codes when working with 120V AC circuits.

Packaging List

When you receive your Allen-Bradley 1734-IA4, the package contains the following items:

• One 1734-IA4 120V AC discrete input module

• One removable terminal block (depending on base variant)

• One set of labeling strips for channel identification

Please note that the terminal base (1734-TB, 1734-TBS, 1734-TOP, or 1734-TOPS) is not included with the module and must be ordered separately. Additionally, the package does not include cables, power supplies, or network adapters. All components are shipped in anti-static packaging to prevent electrostatic damage during transit.

Shipping Information

We ship all orders using reliable express courier services. Specifically, we dispatch via FedEx, UPS, or DHL, depending on your location and shipping preferences. Every shipment includes a tracking number so you can monitor delivery progress online. Typically, orders placed before 2:00 PM local time are shipped on the same business day. For international destinations, please allow extra time for customs clearance and local handling.

Frequently Asked Questions

1. Is the 1734-IA4 compatible with DC input signals?
No. The 1734-IA4 is strictly designed for 120V AC input signals. Applying DC voltage or lower AC voltages may result in incorrect readings or permanent damage to the module. For DC applications, consider modules such as the 1734-IB8 or 1734-IB16.

2. What terminal bases work with the 1734-IA4?
The 1734-IA4 mounts onto 1734-TB, 1734-TBS, 1734-TOP, or 1734-TOPS wiring base assemblies. These bases provide the physical and electrical connections for the module and its field wiring.

3. Can I install multiple 1734-IA4 modules in one system?
Yes. You can install multiple 1734-IA4 modules in a single POINT I/O bank, subject to the power budget and I/O capacity of the host processor. The POINTBus current of 75 mA per module helps you calculate the total load.

4. How do I know if the 1734-IA4 input is active?
Each input channel on the 1734-IA4 has a dedicated LED indicator. When the channel is energized with a valid AC signal (above 65 VAC), the corresponding LED turns on. A dark LED indicates that the input is de-energized or below the On-state threshold.

5. Does the 1734-IA4 provide isolation between input channels?
No. The 1734-IA4 features non-isolated inputs. All four channels share a common return path. However, the module does provide isolation between the field side and the system backplane, rated at 240V AC continuous.