GE IC694APU305 Pulse I/O Module RX3i

IC694APU305 GE Fanuc RX3i Pulse I/O Processing Module

Product Introduction

The IC694APU305 is a specialized pulse I/O processing module from GE Fanuc, designed for the RX3i PacSystems platform. This module excels at handling pulse train signals from devices such as flow meters, motion encoders, and event counters. Notably, the IC694APU305 processes these signals without requiring external PLC or CPU intervention, freeing the main processor for other tasks. It provides DC power for most pulse metering devices connected to its inputs, though external encoders in motion control systems need their own power supply. Both inputs and outputs use positive logic with optical isolation, protecting the module from overcurrent and short-circuit damage. Furthermore, the IC694APU305 imposes no limit on how many units you can install per RX3i system, making it highly scalable for applications with numerous pulse signals.

Technical Specifications

The IC694APU305 operates on a 5V DC supply drawn from the RX3i backplane. Its current consumption is 360 mA plus an additional 10 mA for each faceplate output that is powered on. For isolation, this module provides 1500V peak isolation (1 second) and 30V AC/DC steady-state isolation between field I/O and logic circuits. The input type is positive logic and optically isolated, with a typical input impedance of 4300 Ohms and a hysteresis of 250 mV. Outputs are also positive logic and optically isolated. The maximum supply voltage for field devices is 30V DC. A replaceable 5A fuse (5 x 20 mm) protects all outputs collectively. The IC694APU305 supports high-speed counting at up to 30 kHz with absolute encoders and up to 200 kHz with Quad B encoders. For reliable operation, use shielded wiring with a maximum length of 30 meters for all input connections.

Pulse Signal Processing Capabilities

The IC694APU305 shines in applications requiring fast and accurate pulse processing. Its high-speed counter handles count rates up to 200 kHz when using Quad B encoders, which suits high-resolution motion feedback systems. For absolute encoders, the module supports 30 kHz, still adequate for most flow metering and counting tasks. The IC694APU305 processes these pulse trains independently, so the main CPU does not need to dedicate scan cycles to counting operations. This architecture improves overall system performance, especially in large installations with many pulse inputs. Additionally, the module's positive-logic design simplifies wiring for standard industrial sensors and switches. The optical isolation on both inputs and outputs ensures that electrical noise or voltage spikes on field wiring do not affect the backplane or other modules.

Power Supply and Field Device Support

The IC694APU305 offers a convenient feature: it can supply DC power to most pulse metering devices connected to its inputs. This eliminates the need for separate power supplies for devices like flow meters and proximity sensors. However, external encoders used in motion-controlled systems require their own external power source – the IC694APU305 does not provide encoder power. For output circuits, the module uses a common 5A fuse (5 x 20 mm, replaceable) to protect all outputs from overcurrent conditions. Should the fuse blow, you can replace it easily without changing the entire module. The maximum supply voltage for field I/O is 30V DC, so ensure your external devices operate within this limit. The IC694APU305 draws 360 mA from the backplane, plus 10 mA per active output, so calculate total power consumption when planning your system.

System Scalability and Installation

One standout feature of the IC694APU305 is its unlimited module count per RX3i system. You can add as many modules as needed to monitor all pulse signals in your application. This flexibility makes the IC694APU305 ideal for large-scale systems with hundreds of flow meters, encoders, or counters. Installing the module is straightforward: insert it into any available slot on the RX3i backplane and secure it with the retaining screws. The IC694APU305 draws its 5V power from the backplane, so no external power connection is required for the module itself. For field wiring, always use shielded cables to minimize noise and interference, and keep cable lengths under 30 meters to maintain signal integrity. The IC694APU305 supports both panel and DIN rail mounting through the RX3i rack system.

Input and Output Characteristics

The IC694APU305 features optically isolated inputs and outputs with positive logic. Input impedance is rated at 4300 Ohms with 250 mV hysteresis, providing noise immunity for reliable signal detection. The input circuits can accept signals from a variety of sensors, including proximity switches, photoelectric sensors, and encoder outputs. For outputs, the module drives loads within the 30V DC maximum supply voltage. All outputs share a common 5A fuse, which protects against short circuits and overcurrent events. The IC694APU305 provides field power for most input devices, simplifying wiring and reducing external power supply requirements. When using the IC694APU305 in motion control systems, remember that external encoders need their own power source. The optical isolation ensures that any faults on the field side remain contained, protecting the backplane and other modules from damage.

Count Rate and Performance

Performance-wise, the IC694APU305 delivers impressive counting speeds. With a Quad B encoder, it handles up to 200 kHz, making it suitable for high-speed motion feedback and positioning systems. For absolute encoders, the maximum count rate is 30 kHz, which still covers most flow metering and event counting applications. These rates are processed by the module's dedicated hardware counters, independent of the CPU's scan cycle. Therefore, the IC694APU305 does not degrade system performance even with high-frequency signals. The module supports both up/down counting and quadrature counting modes, offering flexibility for different encoder types. When wiring encoders, remember to use shielded cables and keep lengths under 30 meters to preserve signal quality at high frequencies.

Wiring Guidelines

Proper wiring is essential for reliable operation of the IC694APU305. Always use shielded cables for input connections to protect against electromagnetic interference. The maximum recommended cable length is 30 meters – longer runs may introduce noise that affects counting accuracy. For output wiring, ensure that the total current does not exceed the 5A fuse rating. The IC694APU305 provides field power for most input devices, but if you connect multiple devices, verify that the total power draw stays within the module's capacity. When connecting external encoders that require their own power, use a separate supply and ensure common grounding with the IC694APU305. Follow the terminal labeling on the module faceplate carefully to avoid miswiring. After completing wiring, test each input and output individually before putting the IC694APU305 into full operation.

Common Application Scenarios

The IC694APU305 serves a wide range of industrial applications. Flow metering systems use this module to count pulses from turbine or magnetic flow meters, providing accurate totalization and rate measurement. Motion control systems employ the IC694APU305 for encoder feedback, enabling precise position and speed control. Event counting applications, such as part counting on conveyor lines, also benefit from its high-speed capabilities. Additionally, the IC694APU305 works well in packaging machines that need to track product counts and detect jams. Its unlimited module count makes it suitable for distributed systems where multiple pulse sources are spread across a facility. System integrators often choose the IC694APU305 for its ease of use, optical isolation, and independent processing, which simplifies both hardware design and software development.

Packaging List

Your shipment of the IC694APU305 includes:

• One GE Fanuc IC694APU305 pulse I/O processing module

• One 5A fuse (5 x 20 mm) installed in the fuse holder

• One spare 5A fuse (5 x 20 mm)

• One printed quick-start guide

• One anti-static protective bag

This package does not include shielded cables, external power supplies, encoders, or mounting hardware. Those items must be sourced separately. Additionally, no calibration certificates or warranty documents are enclosed in the box – these are available digitally upon request.

Shipping Information

All IC694APU305 orders ship via premium global couriers: FedEx, UPS, and DHL. Each module receives ESD-protective packaging to prevent static damage during transit. Tracking numbers are sent within 24 hours of order dispatch. Standard international delivery takes 3 to 7 business days, depending on the destination. Express shipping options are available for urgent projects. Please confirm your shipping address is accurate to avoid any delays. All shipments are insured for the full product value.

Frequently Asked Questions

Q1: Can the IC694APU305 power external encoders directly?
No. The IC694APU305 provides DC power for most pulse metering devices on its inputs, but external encoders in motion control systems require their own external power supply. The module does not supply encoder power.

Q2: How many IC694APU305 modules can I install in one RX3i system?
There is no limit. You can install as many IC694APU305 modules as your RX3i system can physically accommodate, as long as your power supply can handle the total current draw (360 mA + 10 mA per active output per module).

Q3: What is the maximum cable length for inputs on the IC694APU305?
The maximum recommended input cable length is 30 meters. Use shielded wiring to minimize noise and interference, especially for high-frequency signals like encoder outputs.

Q4: What happens if the output fuse on the IC694APU305 blows?
The IC694APU305 uses a replaceable 5A fuse (5 x 20 mm) common to all outputs. If it blows, replace it with an identical fuse. Always investigate the cause of the overcurrent before replacing the fuse to avoid repeated failures.

Q5: Does the IC694APU305 process pulse signals independently of the CPU?
Yes. The IC694APU305 handles pulse train processing using dedicated hardware counters. This means the main CPU does not need to manage counting tasks, preserving scan time for other logic operations.