Allen-Bradley EtherNet/IP Absolute Encoders: Standard and CIP Safety Models

Summary of Changes

This publication includes updates to the title, introduction, technical specifications, product overview, and tables. Figures 5, 6, and 7 have been added, and the additional resources table has been updated.

Introduction

This document provides guidance for the proper installation of the EtherNet/IP™ encoder. It includes publication references, guidelines, product specifications, technical data, and cabling recommendations. Installation must be performed by qualified personnel in accordance with these instructions.

Technical Specifications

ATTENTION: Use appropriate screws, bolts, or nuts to mount the encoder flange to prevent tampering. Avoid over-torquing mounting hardware.

The 843ES encoder is designed for safety-related control systems. A risk assessment is required before installation to ensure suitability for the application's operational and environmental characteristics. Refer to Specifications for certification information and ratings.

Product Overview

The 843E/843ES encoders are absolute encoders, providing a unique digital output for each shaft position. This ensures true position availability even after power interruptions. They can be single-turn or multi-turn.

The 843ES model simplifies safety applications by enabling controller-based monitoring functions, facilitating the achievement of desired Safety Integrity Levels (SIL) or Performance Levels (PL) by allowing safety controllers (GuardLogix® 5580 or Compact GuardLogix 5380) to monitor position and velocity inputs.

Specifications

Table 1 - General Specifications

Table 2 - Mechanical Specifications

Table 3 - Resolution/Revolution Specifications

Approximate Dimensions

IMPORTANT: General tolerances according to ISO 2768-1, tolerance class m (medium), apply unless otherwise specified.

Figure 1 - Solid Shaft with Clamping Flange [mm (in.)]: This diagram illustrates the dimensions of a solid shaft encoder with a clamping flange. It shows the main housing diameter (Ø58 mm / 2.28 in.), shaft diameter (ØD f7), and overall length. Mounting hole patterns and specific dimension lines are indicated.

Figure 2 - Solid Shaft with Synchro Flange [mm (in.)]: This diagram shows the dimensions for a solid shaft encoder with a synchro flange. Key features include the housing diameter (Ø58 mm / 2.28 in.), shaft diameter (ØD f7), and mounting hole configurations.

Figure 3 - Solid Shaft with Square Flange [mm (in.)]: This diagram details the dimensions of a solid shaft encoder with a square flange. It highlights the housing diameter (Ø58 mm / 2.28 in.), shaft diameter (ØD f7), and the square mounting pattern.

Figure 4 - Hollow Shaft with Stator Coupling 63 mm (2.5 in.) Diameter [mm (in.)]: This diagram illustrates a hollow shaft encoder with a 63 mm (2.5 in.) diameter stator coupling. It shows the housing dimensions, shaft opening, and mounting points, including insertion depth specifications.

Figure 5 - Hollow Shaft with Stator Coupling 63 mm (2.5 in.) Diameter with Ø 6.35 mm (0.25 in.) Hollow Shaft [mm (in.)]: This diagram shows a hollow shaft encoder with a 63 mm (2.5 in.) stator coupling and a 6.35 mm (0.25 in.) hollow shaft. It details the housing, shaft opening, and mounting dimensions, with specific attention to the shaft insertion depth.

Figure 6 - Hollow Shaft Flange with 150 mm (5.9 in.) Torque Arm [mm (in.)]: This diagram displays a hollow shaft encoder featuring a 150 mm (5.9 in.) torque arm. It includes housing dimensions, shaft opening, and the torque arm mounting details.

Figure 7 - Hollow Shaft Flange with 150 mm (5.9 in.) Torque Arm and Ø 6.35 mm (0.25 in.) Hollow Shaft [mm (in.)]: This diagram illustrates a hollow shaft encoder with a 150 mm (5.9 in.) torque arm and a 6.35 mm (0.25 in.) hollow shaft. It provides housing dimensions, shaft opening, and torque arm mounting specifications.

Figure 8 - Application Requirements for Hollow Shaft Encoders: This diagram shows a cross-section of a hollow shaft encoder, indicating the mating shaft requirements. It specifies the material as Stainless steel and highlights the need for a specific surface finish (Ra 1.6) and a minimum insertion depth (25.5 mm / 1.0 in.).

Figure 9 - Flexible Shaft Couplings: This diagram illustrates the concepts of axial offset, radial offset, and angular offset when connecting encoder shafts to machine shafts using flexible couplings.

Encoder Installation

ATTENTION: Ensure the encoder slides freely onto the shaft. If resistance is met, do not force it. Check the shaft for any obstructions like gouges, burrs, rust, or incorrect sizing.

IMPORTANT: Do not stress the flex mount while tightening screws.

Mount with a Solid Shaft

IMPORTANT: For solid shaft encoders, use a suitable shaft coupling that meets the application's requirements.

1. Select the correct size flexible coupling clamp for the encoder shaft. Refer to publication 847-TD001 in Additional Resources for encoder accessories.
2. Determine encoder mounting hole locations using the Approximate Dimensions section.
3. Fasten the encoder using three M3 mounting screws (provided with the flange).
4. Tighten screws to 1 N·m (8.9 lb·in) and secure them to prevent loosening.
5. Check shafts for offset; permissible tolerances depend on the selected shaft coupling.
6. Connect the encoder and load shaft using a flexible coupling.
7. During assembly, protect the coupling element from excessive bending and damage.
8. Center the flexible coupling, screw it without preload, and secure it against loosening.
9. Rotate the machine slowly to verify the flexible coupling is not deforming beyond specifications.
10. Align the machine to its mechanical zero or home position.

Mount with a Hollow Shaft

IMPORTANT: For hollow shaft encoders, coupling elements (e.g., stator coupling or compensating torque stop) are factory-mounted.

• Verify the insertion depth of the load shaft into the hollow shaft encoder is ≥25.5 mm (1.0 in.).
• Verify the mating shaft is chamfered and grease-free.

1. Check shafts for offset. Maximum allowed shaft connection tolerances: Axial offset < ±0.25 mm (0.01 in.); Radial offset < ±0.20 mm (0.008 in.).
2. Slide the encoder onto the mating shaft until the flex mount rests on the machine surface. Minimum insertion depth for hollow shaft is 25.5 mm (1.0 in.).
3. Hold the encoder firmly and mark the two mounting holes. If mounting holes are present, proceed to step 6.
4. Slide the encoder off. Drill and tap the marked holes to accept M3 (or equivalent) screws.
5. Slide the encoder back onto the shaft until the flex mount rests on the machine surface.
6. Attach the encoder with two M3 (or equivalent) screws. Screw the stator coupling and torque stop without preload onto the drive flange. Tighten screws to 1 N·m (8.9 lb·in).
7. Tighten the clamping ring screw to 2.5 N·m (22.1 lb·in).
8. Align the machine to its mechanical zero or home position.

Electrical Installation

ATTENTION:

• Ensure the operating voltage is switched on or off simultaneously for the encoder and the downstream device.
• Electrostatic discharges at connector contacts or cable ends can damage or destroy the device. Take appropriate precautionary measures.
• Use a PELV supply voltage source according to IEC 60204-1, complying with the proper operating voltage and maximum permissible output current.

IMPORTANT:

• For encoder connection, refer to the operating and safety instructions of the external drive system/encoder evaluation system.
• When assembling a mating connector, follow the instructions provided with the connector.
• Verify all required cable wires/connectors are connected before commissioning. Insulate unused output signal ends individually to prevent short-circuits.

Route the encoder cable without tension to avoid applying additional force to the encoder. Consider the minimum bending radius of the connection cable.

Connectivity Considerations

ATTENTION: Before connecting or disconnecting the signal cable, always disconnect the power supply and secure it against accidental re-energization.

• Use the shortest possible lengths for both Ethernet and power cables.
• Run Ethernet cables separately from power cables and keep DC power cables away from AC power.
• Verify that no high-interference devices (e.g., frequency converters, solenoid valves, contactors) are connected to the same power supply as the encoder. Use suitable voltage filtering if necessary.
• Shielded twisted-pair cables are recommended for both Ethernet and power connections to mitigate disruptions from electrical noise, mechanical vibration, and shock. Follow recommended installation guidelines for shielded cables to avoid ground loops. Comply with maximum permissible connection cable length.
• For shielded Ethernet cables, an equipotential grounding network is required, overlaying the existing electrical grounding and bonding system for safety and fire prevention. If an equipotential ground cannot be provided and the second connection goes to a switch, install a patch panel to break the shield to the switch. Switches typically connect jack shields directly to the ground lug.

Diagnostics

After power-on, wait at least 10 seconds for the encoder to become ready for operation and communication. The encoder communicates via the digital interface after this period.

Module Status Indicator

Network Status Indicator

Encoder Status Indicator

Link 1/Link 2 Status Indicator (1)

(1) The Ethernet link status indicators (Link 1 and Link 2) display the status of the physical connection on the Ethernet interface.

Rotary Switches

• Set switches in the range 001-254 to set IP address 192.168.1.xxx (where xxx is the switch setting).
• Subnet mask: 255.255.255.0
• Gateway address: 192.168.1.1
• It is recommended to set rotary switches to a valid number before installing the module.
• If rotary switches are not set to a valid number, the encoder attempts to use a BOOTP/DHCP server to set the IP address.
• The encoder is shipped with: BOOTP/DHCP enabled; Rotary switches set to 999 (when applicable).

ATTENTION: The EtherNet/IP communication module must be assigned a fixed network address. The IP address must not be provided dynamically. Failure to comply can result in unintended machine motion or loss of process control.

Declaration of Conformity

For the Declaration of Conformity, visit rok.auto/certifications.

Additional Resources

To download publications, visit rok.auto/literature and search for the publication numbers:

Waste Electrical and Electronic Equipment (WEEE)

At the end of its life, this equipment should be collected separately from any unsorted municipal waste.

Rockwell Automation maintains current product environmental compliance information on its website at rok.auto/pec.