Emergency Stop Switch: Functions, Regulations & Key Differences Explained

Table of contents

1. What is an Emergency Stop Switch?
2. How Does an Emergency Stop Switch Work?
3. What is the Function of an Emergency Stop Switch?
4. Emergency Stop vs. Emergency Halt – What’s the Difference?
5. Types and Designs of Emergency Stop Switches
6. How to Connect an Emergency Stop Switch
7. IDEC Emergency Stop Switches: Safety with a System
8. When Can an Emergency Stop Be Omitted?
9. Standards & Regulations: DIN EN ISO 13850
10. Safety at the Push of a Button with an Emergency Stop Switch

What is an Emergency Stop Switch?

An Emergency Stop switch (also called an E-Stop switch) is a safety device manually activated in an emergency to immediately stop machines, equipment, or entire processes. Typically, it’s placed in a highly visible location and is easy to use, for example, as a red button with a yellow background.

How Does an Emergency Stop Switch Work?

When an Emergency Stop switch is pressed, the circuit is interrupted or a safety relay is activated, which immediately halts the machine’s operation. In most cases, the switch remains locked and must be manually reset to restart the machine. Some switches, such as the key-operated Emergency Stop switch, require authorized access for resetting – a critical measure to prevent unauthorized reactivation.

What is the Function of an Emergency Stop Switch?

The primary function of an Emergency Stop switch is to respond quickly to life-threatening situations or machine malfunctions. Key functions include:

• Rapidly stopping dangerous movements
• Preventing injuries and accidents
• Protecting production equipment
• Ensuring compliance with legal safety requirements

Emergency Stop vs. Emergency Halt – What’s the Difference?

Although these terms are often used interchangeably, there are clear technical distinctions:

Types and Designs of Emergency Stop Switches

Depending on the application and safety requirements, various types of Emergency Stop switches are available:

• Classic E-Stop: The most common type, featuring a large red button on a yellow background for easy identification and activation.
• Pull Cord Switches: Ideal for conveyor belts or large machines. A cord allows activation over long distances.
• Key-Operated Emergency Stop Switches: These switches can only be reset by authorized personnel, enhancing operational safety.
• Contactless Systems: Modern variants with sensor-based activation, offering a hygienic and wear-free option.

How to Connect an Emergency Stop Switch

Connecting an Emergency Stop switch should always be done by qualified personnel. The standard procedure includes:

• Integration into the control circuit: Interrupting the power supply upon activation.
• Incorporation into safety relays or safety controllers: Enhancing safety and enabling diagnostic functions.
• Compliant labeling: Colors and symbols must adhere to the relevant standards (red and yellow, with the “mushroom” symbol).

Symbols & Circuit Diagrams

In circuit diagrams, the Emergency Stop switch is typically represented by a stylized circle with a horizontal bar, or by an abbreviation like “S1”. It’s important that these symbols are clearly recognizable as safety functions. The symbol for Emergency Stop is standardized according to DIN EN 60617.

Placement & Labeling

The placement of the Emergency Stop switch is crucial:

• It must be clearly visible and easily accessible at all times.
• Do not place it near start/stop buttons.
• Ensure it is not obstructed.
• Additional labeling is usually not necessary.

Resetting & Restarting

After activation, the switch remains locked. Resetting is done by:

• Turning (for classic e-stop buttons)
• Pulling (for pull cord switches)
• Or using a key (for authorized models)
• The machine can only be restarted after a controlled reset.

The XW Series from IDEC: Innovation for Maximum Safety

The Emergency Stop switches of the XW Series from IDEC set new standards in safety technology. Based on the revolutionary “Safe Break Action” technology, they offer a unique protection concept: Unlike conventional Emergency Stop switches, which rely on spring force to keep contacts in a closed position, the XW Series uses spring pressure to reliably separate the contacts in case of damage. Even if the switch is damaged or the contact blocks are detached, the circuit is reliably interrupted – preventing injuries and machine damage.

The XW models also stand out for their particularly compact design: With an installation depth of only 48mm behind the control panel and up to four secure contacts, they are perfect for high-safety applications (Level 4).

Another key feature is the new smooth button option, which prevents dirt accumulation – ideal for hygiene-sensitive environments like food, beverage, and pharmaceutical industries.

Practical features such as a visible green status indicator for remote monitoring and flexible reset options (via turning or pulling) make operation more intuitive and safe. The robust, IP65-rated switches are certified to international standards such as ISO 13850:2015, IEC60947-5-1, and UL NISD, and can withstand extreme conditions in emergency situations.

The IDEC XW Series offers cutting-edge safety technology – thoughtful, reliable, and versatile.

When Can an Emergency Stop Be Omitted?

An Emergency Stop switch is not mandatory in every case. According to standards, it can be omitted if:

• There is no risk to people or machines.
• The system only performs non-dangerous movements.
• Alternative safety measures (e.g., mechanical separation) are in place.

Important: In such cases, a documented risk analysis is essential.

Standards & Regulations: DIN EN ISO 13850

The DIN EN ISO 13850 standard is the key regulation for Emergency Stop devices. It covers:

• Color and form (red on yellow)
• Accessibility and reachability
• Locking mechanisms
• Manual resetting
• Requirements for function and design

It ensures that Emergency Stop switches function consistently and reliably worldwide.

Safety at the Push of a Button with an Emergency Stop Switch

An Emergency Stop switch is much more than just a red button – it’s a central element of modern machine safety. Whether as a classic e-stop button, pull cord switch, or contactless system: Knowing the differences, adhering to DIN EN ISO 13850, and using high-quality products – like those from IDEC – creates a safe working environment for both people and machines.