LS ELECTRIC XSR Series Safety Relay User Manual

Safety Relay

Model: XSR-ES2C, XSR-ES2S

Description: The XSR-ES2 Safety Relay monitors two inputs from safety gates, safety guards, or similar (two-channel electromechanical safety switches).

Key Features:

• Compatible with international safety standards: SIL3 (IEC61508), SILCL3 (IEC62061), Category 4 (ISO 13849-1).
• Compact size for space saving.
• User convenience functions: Input for safety gate/guard, selectable manual/automatic restart, 2 N.O. outputs with guided contacts, 1 system monitor PNP output, 1 external contactor feedback input.

Safety Instructions

Warning:

• Read this manual carefully before installing, wiring, operating, servicing, or inspecting this equipment.
• Keep this manual within easy reach for quick reference.
• Safety instructions should always be observed to prevent accidents or risks.
• Instructions are separated into "Warning" (serious injury or death) and "Caution" (slight injury or product damage).
• Symbols on the product and manual indicate potential danger or electric shock.

Warning: Safety Instructions when designing

• Install protection circuits on the exterior of the RELAY to protect the control system from external power errors.
• Install applicable protection units to protect the system from physical damage.
• If a system error is detected during CPU operation, the output is designed to turn off. However, if the CPU error is not detected on the output device itself, the output may remain on, potentially causing serious problems. An additional circuit to monitor output status is recommended.
• Never connect overloads exceeding the rated capacity or allow output circuits to short circuit, as this may cause a fire.
• Ensure external power for the output circuit is not turned on earlier than RELAY power to prevent abnormal operation.
• Install interlocks in the sequence program for data exchange between computers or other external equipment and the RELAY to protect the system from errors.

Caution: Safety Instructions when designing

• Wire I/O signal lines at least 100mm away from high-voltage cables or power lines to prevent abnormal output or operation.
• Use the RELAY only in the specified environment.
• Before installing, ensure the RELAY power is off to prevent electric shock or damage.
• Ensure all modules are securely fastened to prevent abnormal operation, errors, or dropping.
• Ensure I/O or extension connectors are securely fastened to prevent electric shock, fire, or abnormal operation.
• If significant vibration is expected, avoid direct vibration to the RELAY.
• Prevent metallic foreign materials from entering the product.

Warning: Safety Instructions when wiring

• Prior to wiring, ensure RELAY and external power are turned off.
• Before powering on the system, ensure all terminal covers are securely closed.

Caution: Safety Instructions when wiring

• Install wiring correctly after checking voltage ratings and terminal arrangements.
• Secure terminal screws tightly with specified torque. Loose screws can cause short circuits or fire.
• Use Class 3 ground wire for PE terminals. Incorrect grounding can cause abnormal operation.
• Prevent wiring waste or foreign materials from entering the module during wiring.

Warning: Safety Instructions for test-operation or repair

• Do not touch terminals when powered.
• Before cleaning or tightening terminals, turn off all external power, including RELAY power.
• Do not recharge, disassemble, heat, short, or solder batteries, as this can cause injuries or fire.

Caution: Safety Instructions for test-operation or repair

• Do not remove the PCB from the module case or remodel the module.
• Before installing or disassembling, turn off all external power, including RELAY power.
• Keep wireless devices or cell phones at least 30cm away from the RELAY.

Caution: Safety Instructions for waste disposal

• Product or battery waste must be processed as industrial waste.

Caution: Precautions for Building a Safety System

• Ensure all tasks related to building a safety system are conducted by trained technicians.
• Use products that meet required safety levels and category specifications for safety functions.
• Conduct a test run before operationalization to ensure all safety devices function correctly and complete safety verification.
• Do not operate the system without safety verification, as compromised safety functions pose a risk of severe injury.
• Confirm that the calculated safety response time meets specifications.
• Do not use non-safe signals and data for controlling safety-related functions.
• Do not use the LED of safety modules for controlling safety-related functions.
• The customer is responsible for compliance with the established safety system.

Chapter 1 Introduction

1.1 How to Use this User's Manual

This user's manual provides information on the specifications, performance, functions, and operation required for using the XSR Series Safety Relay. The manual is structured as follows:

1.2 Features

The XSR-ES2 Safety Relay offers the following features:

• Monitors two inputs from safety gates, safety guards, or similar (two-channel electromechanical safety switches).
• Compatibility: Meets international safety standards including SIL3 (IEC61508), SILCL3 (IEC62061), and Category 4 (ISO 13849-1).
• Compact Size: Innovative compact design saves space.
• System Configuration: Includes user convenience functions such as inputs for safety gate/guard, selectable manual/automatic restart, 2 N.O. outputs with guided contacts, 1 system monitor PNP output, and 1 external contactor feedback input.

1.3 Terminology

Key terms used in this document include:

Chapter 2 General Specifications

2.1 General Specifications

The general specifications for the XSR series are as follows:

Notes:

• IEC (International Electrotechnical Commission): An international organization promoting standardization in the electric/electronic field.
• Pollution degree: Indicates the operating environment's pollution level, affecting device insulation performance. Degree 2 typically means non-conductive pollution, but temporary conduction due to dew may occur.

Chapter 3 Safety Relay Module

3.1 Performance Specifications

The performance specifications of the XSR-ES2 are presented below:

3.2 Part Names and Functions

Front View:

• (1) IN1 LED: Green ON: Input contact 1 CLOSED; Green OFF: Input contact 1 OPEN.
• (2) IN2/FAIL LED: Red ON: Fault detected; Green ON: Input contact 2 CLOSED; OFF: Input contact 2 OPEN.
• (3) GUARD/BREAK LED: Red ON: Output relays opened; Red blinking: Number of blinks indicates FAIL type (only with red FAIL led ON); Green ON: Output relays closed; Yellow ON: Input ON; Yellow OFF: Output OFF, waiting for Restart.

Top View:

• (4) IN/Out Connector: DC 24V power supply terminal block for the Safety Relay (+24V, 24G, PE). In/Out Port terminal block for the Safety Relay. Product model name varies by connector type: C: Clamp type, S: Screw type.

3.3 IO Port Pinout and Functions

3.4 LED Indicator

Diagnostic Operation LED Indicator:

3.5 OPERATING MODES

3.5.1 AUTOMATIC MODE

This mode is activated by connecting the RESTART (terminal 4) directly to 24VDC.

• In Automatic Mode, the outputs of the safety module follow the status of the safety relay inputs (terminals 7, 8) coming from the safety guard.
• With the safety relay inputs active, the relay outputs are active.
• With the safety relay inputs not active, the relay outputs are de-activated.

Diagram: Figure 1 - Automatic operation with K1 K2 relays (shows wiring connections for automatic mode).

• Manual mode (start/restart interlock activated) is mandatory when the safety device controls access to a danger zone, especially if a person might remain undetected. Failure to comply can result in serious risks.
• If K1-1 and K2-1 N.C. control contacts are not used, terminal 11 (K1 K2 FBK) must be connected to terminal 12 (SYS STATUS).

3.5.2 MANUAL MODE

In Manual Mode, the safety relay outputs are activated only if the safety relay inputs (terminals 7, 8) are both active and a RESTART signal is sent via a push-button or a specific command on the RESTART input (terminal 4).

• The RESTART command is active with a 24VDC voltage.
• If the RESTART signal is permanently connected to 24VDC, the safety module operates in automatic restart mode.

Diagram: Figure 2 - Manual operation with K1 K2 relays (shows wiring connections for manual mode). Note: If pin 4 is permanently connected to 24VDC, the module works in automatic restart mode.

3.5.3 SIMULTANEITY CHECK

The XSR-ES2 Safety Relay module monitors two inputs from a safety gate, safety guard, or similar (two-channel electromechanical safety switch). Short circuits between channels or to 24VDC are detected via OUT TEST1 and OUT TEST2 signals. A simultaneity check between the two channels is performed within 1 second.

• If simultaneity is not respected, the system remains OFF with alternating flashing of the IN1 and IN2/FAIL LEDs. To reactivate outputs, INPUT1 and INPUT2 must be opened and closed again simultaneously.

Chapter 4 IO Port SIGNAL

4.1 INPUT

4.1.1 RESTART command

The RESTART command allows the XSR-ES2 to manage manual operation. It must be installed outside the danger area, with a clear view of the danger area and work area, and unreachable from within the danger area.

• The RESTART command is sent by connecting terminal 4 to 24VDC.
• The contact used for the RESTART command must switch 24VDC and 10mA, with a closing time greater than 100ms.
• The total SYSTEM RESET TIME is the sum of the reset time of external contactors K1-K2 and the reset time of the XSR-ES2.

Diagram: Shows the timing for the RESTART command.

4.1.2 K1K2 FEEDBACK input

For K1 and K2 auxiliary safety contactors with guided contact safety type, connect +24VDC to K1 K2 FBK through the K1-1 and K2-1 N.C. control contacts in series.

• The correct switching of K1 and K2 is controlled with a 300ms delay.
• If required, verify the response time of external contactors with an additional device.
• If K1-1 and K2-1 N.C. control contacts are not used, connect terminal 11 (K1K2 FEEDBACK) to terminal 12 (SYSTEM STATUS).

4.2 OUTPUTS

4.2.1 SYSTEM STATUS output

The SYSTEM STATUS output reflects the condition of the output safety relays:

• When output relays are open, SYSTEM STATUS reports 0VDC.
• When output relays are closed, SYSTEM STATUS reports +24VDC.

1. Characteristics of the output circuit:

• The safety relay module uses two guided contact safety relays.
• Relays are rated for voltage and current values above those in the technical data. Protect each output line with an appropriate fuse.

2. Use of K1 and K2 auxiliary contact elements:

• For loads with higher voltage and current characteristics, use auxiliary external relays or contactors.
• K1 and K2 auxiliary contactors/relays must be of the guided contact safety type.
• Pay attention to the configuration of control contacts on terminal 11 and the use contacts.

• Control contacts K1-1 and K2-1 (terminal 11) must switch 10mA at 24VDC.

Chapter 5 Installation and Wiring

5.1 Installation

5.1.1 Environment

The product offers high reliability regardless of environmental conditions. However, to maintain reliability and stability, observe the following:

1) Environmental conditions:

• Install in a waterproof and dust-proof cabinet.
• Avoid continuous impact or vibration.
• Avoid direct sunlight.
• Avoid rapid temperature changes that may cause dew formation.
• Ambient temperature: 0~60 °C.
• Relative humidity: 5~95%.
• Avoid corrosive or flammable gases.

2) Installation Work:

• Protect the MODULE from foreign materials during installation and wiring.
• Select a position suitable for operation.
• Do not install in the same panel as high-voltage devices.
• Maintain at least 50 mm space between wire ducts and adjacent modules.
• Ground the MODULE to a point with a favorable noise environment.

3) Control panel heat dissipation design:

• Consider heat generated by the MODULE and other devices within a sealed control panel.
• If using vents or fans, install filters or use a sealed heat exchanger to prevent dust, gases, or contaminants from affecting the system.

5.1.2 Cautions for handling

• Do not drop or shock the unit.
• Do not separate the PCB from the case.
• Protect the module from debris during wiring; remove any foreign material.
• Do not connect or disconnect the module while power is on.
• Use standard cables with lengths not exceeding the maximum allowable length.
• Keep communication lines away from surge and induction noise from AC lines.
• If cables are laid in conduits, ground the conduits.
• Grounding of conduits is necessary when wiring using conduits.

5.1.3 Cautions for wiring

• Do not lay AC power lines and external signal lines close together; maintain at least 100 mm distance or use conduits.
• Select wires considering ambient temperature and allowable current, with a minimum size of AWG 12-30 (UL).
• For power source monitoring, twist wires densely and keep paths short (max. 15m).
• Keep wires away from heat sources, oil, or harmful materials to prevent short circuits.
• Keep wires away from high voltage and power lines to avoid induction interference.
• Total wiring length for safety inputs and test pulse outputs should be less than 100m.
• Wiring length between safety outputs and output devices should be less than 100m.

5.1.4 Installation and removal of module

To install the Safety Relay unit on a 35mm DIN rail:

1. Fasten the Safety Relay to the rail, pressing gently until it snaps into place.
2. To remove, pull down the locking latch on the back of the unit with a screwdriver and lift upwards.

Diagrams: Illustrate the installation and removal process.

5.1.5 Cautions for installation

• General precaution: The Safety Relay turns off output if any problem is detected. Configure external circuits to cut off power to the load when the output is turned off to prevent accidents.
• When changing data, program, or status, provide an interlock circuit for safe operation. Read the manual carefully and determine the operating sequence. Prepare countermeasures against communication errors for PC control.
• If a safety function is activated and output is cut off, use a reset button interlock to prevent unauthorized manual restarting.
• If the temperature inside the operation panel may exceed the allowable range, install a heat exchanger to control temperature. Using a ventilation fan may introduce dust.

Installation Checklist:

5.2 Wiring

5.2.1 Power supply

• Use a power source with low line-to-line and line-to-ground noise. Use an insulation transformer if noise is high.
• Separate power supplies for the MODULE, input/output devices, and power devices.
• Twist power cables tightly and connect them at the shortest distance.
• Keep DC24V cables at least 100mm away from main circuit cables (high voltage, high current) or input/output signal cables.
• Use a surge absorber for protection against lightning and other surges.
• Use an isolation transformer or noise filter if noise interference is a concern.
• Twist input/output power wiring tightly. Ensure shielding transformer or noise filter wiring does not pass through ducts.
• Use the same ground connection (OVDC) for all system components.

Diagram: Shows wiring with a Lightning Surge Absorber.

Notes:

• Separate the grounding (E1) of the surge absorber from the grounding (E2) of the MODULE.
• Select a surge absorber that does not exceed the maximum allowable voltage during maximum voltage rise.

5.2.2 Input/Output Device Wiring

• Wire size range: AWG 12-30 (solid/stranded) (UL).
• Separate input and output wires.
• Wire input/output cables at least 100mm away from main circuit cables with high voltage and high current.
• If separation is not possible, use a combined shielded cable and ground the MODULE side.
• Ensure conduits are properly grounded when wiring through them.
• Terminal tightening torque: 5-7 lb-in (0.6-0.7 Nm).

5.2.3 Grounding circuit

• The MODULE has sufficient anti-noise measures; grounding is not necessary unless the system is subject to high noise levels. If grounding is needed, consider the following:
• The ground circuit should be exclusive if possible. Grounding work shall be Class 3 (resistance ≤ 100 Ω).
• If exclusive grounding is unavailable, use a common grounding circuit (acceptable). Avoid common grounding (unacceptable).
• Ground wire shall be at least 2 mm². Grounding point should be as close to the MODULE as possible.

Diagrams: Illustrate exclusive, acceptable common, and unacceptable common grounding.

5.2.4 wire specification

• Wire size range: AWG 12-30 (solid/stranded) (UL).
• Use 60/75°C copper (Cu) conductor only.
• Use separate power supplies for the Safety Relay and other electrical equipment (motors, inverters) or disturbance sources.
• Cables for connections longer than 50m must have a cross-section of at least 1mm² (AWG16).

Chapter 6 Maintenance

6.1 Inspection and Maintenance

Daily and regular maintenance are crucial for maintaining the Safety Controller in optimal condition. The expected lifetime is about 20 years, but environmental impact can cause damage.

The following items should be inspected 1-2 times per half year:

6.2 Daily Inspection

Daily inspection items:

6. 3 Regular Inspection

Check the following items biannually and take corrective actions as necessary:

NOTE:

• Comply with instructions for daily and regular inspections as specified in each device's manual, including all devices configured in the safety application.
• During daily/regular inspections, ensure all safety functions operate correctly as intended.

Chapter 7 EMC Compliance

7.1 Requirements Complying with EMC Specifications

EMC Directions aim to prevent emission of strong electromagnetic waves and influence from external electromagnetic waves. This chapter summarizes how to structure a system using XSR Relay to comply with EMC directions. The data presented are summarized for requirements and specifications of EMC regulation. However, it does not guarantee that every system manufactured according to this description meets the specifications. The method and determination to comply with EMC directions should be finally determined by the system manufacturer.

7.1.1 EMC specifications

The EMC specifications affecting the PLC are as follows:

Notes:

• *1: QP: Quasi Peak, Mean: average value
• *2: PLC is a type of open device (installed on another device) and to be installed in a panel. For any applicable tests, the system is tested with the system installed in a panel.

7.1.2 Panel

The Safety Relay is an open device and must be installed in a panel to prevent electric shock and attenuate noise. The panel specifications are as follows:

1) Panel:

• The panel for PLC should be installed and manufactured as follows:
• Panel material: SPCC (Cold Rolled Mild Steel).
• Plate thickness: 1.6mm or thicker.
• Power supply to the panel should be protected against surge using an insulated transformer.
• The panel structure should prevent electric wave leakage. The door should be designed as a box, and the main frame covered by the door to restrict radiating noise.
• The inside plate of the panel should have proper conductivity, with plating of the bolt used for mounting on the main frame eliminated to secure electric contact with the frame.

Diagram: Shows a typical panel structure with door and main frame.

2) Power cable and grounding cable:

• The panel should be grounded with a thick wire for low impedance, even at high frequencies.
• LG (Line Ground) terminal and PE (Protect Earth) terminal allow noise inside the PLC to flow to the ground.
• Use a wire with low impedance.
• Keep grounding cables thick and short to prevent them from acting as an antenna.

7.1.3 Cable

• Fixing a cable in the panel: Extension cables should be installed 1cm or more away from the metallic panel to prevent direct contact. This spacing helps prevent the metallic plate from shielding noise while also preventing the cable from acting as a noise source or antenna. Fast signal cables and extension cables require proper spacing from the panel.
• Ferrite core: Recommended for use when cables are exposed outside the control panel and cable shielding is insufficient for noise reduction.

Appendix 1 PFH Value

PFH values for different load conditions:

Appendix 2 Dimensions

Dimensions are in mm:

Diagrams: Show front, top, and side views with dimensions.

• Overall Height: 113.50 mm
• Width: 22.50 mm
• Depth: 99.00 mm

Warranty and Environmental Policy

Warranty

1. Warranty Period: The product is guaranteed for 36 months from the date of manufacturing.

2. Scope of Warranty:

• Initial fault diagnosis is conducted by the customer's company. LS ELECTRIC or its service network can perform this for a fee. If the fault is due to LS ELECTRIC, the service is free.
• Warranty applies only if the product is used under normal conditions as described in the handling instructions, user manuals, catalogs, and caution labels.
• Paid repairs apply in the following cases, even within the free warranty period:
  1. Replacement of consumable and life-limited parts (e.g., relays, fuses, capacitors, fans, LCDs, batteries).
  2. Failures or damage due to improper storage, handling, negligence, or customer accidents.
  3. Failures resulting from customer's hardware or software design.
  4. Failures due to modifications without LS ELECTRIC's consent.
  5. Failures that could have been avoided if safety devices required by legal regulations or common industry standards were incorporated into the customer's equipment.
  6. Failures that could have been prevented if maintenance and replacement of consumable parts were performed normally according to instructions.
  7. Failures and damages caused by using connected equipment or inappropriate consumables.
  8. Failures caused by external factors like fire, abnormal voltage, force majeure, and natural disasters (earthquakes, lightning, salt damage, wind, flood).
  9. Failures due to reasons not predictable with scientific and technical standards at the time of shipment.
  10. Other failures, damages, or defects recognized as the customer's responsibility.

Environmental Policy

LS ELECTRIC Co., Ltd. supports and observes the environmental policy:

• Environmental Management: LS ELECTRIC considers environmental preservation a preferential management subject, and all staff endeavor for environmental preservation.
• About Disposal: The LS ELECTRIC PLC unit is designed to protect the environment. For disposal, separate aluminum, iron, and synthetic resin (cover) from the product as they are reusable.

Contact Information

LS ELECTRIC Co., Ltd.

Headquarter: LS-ro 127(Hogye-dong) Dongan-gu, Anyang-si, Gyeonggi-Do, 14119, Korea

Seoul Office: LS Yongsan Tower, 92, Hangang-daero, Yongsan-gu, Seoul, 04386, Korea

Tel: 82-2-2034-4033, 4888, 4703 Fax: 82-2-2034-4588

E-mail: automation@ls-electric.com

Website: www.ls-electric.com

Disclaimer of Liability: LS ELECTRIC has reviewed the information in this publication for consistency with the described hardware and software. However, LS ELECTRIC cannot guarantee full consistency or be responsible for damages, as variances cannot be precluded. Please check the publication version before use. LS ELECTRIC Co., Ltd 2015 All Rights Reserved.