Safety Relay for Machinery Safety - Specifications and Verification

Product Specifications

Technical details and manufacturing context for Safety Relay

Definition

A safety relay is a critical component within a safety interlock circuit. It is responsible for monitoring the status of safety devices such as emergency stop buttons, safety gates, light curtains, or two-hand controls. When a safety device is triggered, the safety relay ensures the machine enters a safe state, typically by de-energizing power to hazardous functions, and prevents automatic restart until all safety conditions are manually reset. It is designed with redundant contacts, self-monitoring circuits, and forced-guided mechanisms to prevent failure modes that could compromise safety. This product is a component intended for integration into machinery control systems. It is not a standalone safety system and must be used in accordance with the manufacturer's instructions and applicable standards. The relay is available with a rated control supply voltage of 24 V DC, contact rating of 6 A (AC-15 at 230 V), and 3 normally open plus 1 normally closed safety contacts. Its response time is ≤30 ms, and it is suitable for safety functions up to SIL 3 per IEC 61508. Mechanical endurance is 10^7 operations, electrical endurance is 10^5 operations at rated contact current. Ambient operating temperature range is -25 to 55 °C, degree of protection is IP20, terminal type is screw (cage clamp optional), mounting is on 35 mm DIN rail, width is 22.5 mm, and approximate weight is 0.2 kg. All specifications are reference values and must be verified with the legal manufacturer for the specific model and application. Compliance with standards such as IEC 60947-5-1, IEC 61508, IEC 60529, and EN 60715 is a procurement reference and does not imply certification of this specific unit.

Working Principle

The safety relay operates by receiving input signals from safety devices. It continuously monitors these signals for faults such as short circuits, wire breaks, or contact welding. Using internal redundant and cross-monitored circuits, it processes the signals. If all inputs indicate a safe condition, it energizes its output contacts, allowing power to flow to the machine's control circuit. If any input indicates an unsafe condition or a fault is detected, it immediately de-energizes its outputs, cutting power to hazardous parts of the machine. Manual reset is typically required after a fault or safety device activation to restore operation.

Common Materials

Electrical Contacts (Silver Alloy), Coil (Copper Wire), Housing (Thermoplastic)

Technical Parameters

Parameter	Typical range	Notes & selection driver
Rated Control Supply Voltage	24 V DC	Other voltages available on requestIEC 60947-5-1
Contact Rating	6 A	AC-15 at 230 VIEC 60947-5-1
Number of Safety Contacts	3 NO + 1 NC	NO = normally open, NC = normally closed
Response Time	≤30 ms	Time from input signal to contact openingIEC 61508
Safety Integrity Level (SIL)	SIL 3	Suitable for safety functions up to PL eIEC 61508
Mechanical Endurance	10^7 operations	No load switchingIEC 60947-5-1
Electrical Endurance	10^5 operations	At rated contact currentIEC 60947-5-1
Ambient Operating Temperature	-25–55 °C	Non-condensing humidityIEC 60947-5-1
Degree of Protection	IP20	Terminals protected against finger contactIEC 60529
Terminal Type	Screw	Cage clamp optional
Mounting Type	35 mm DIN rail	Snap-on mountingEN 60715
Width	22.5 mm	Housing width
Weight	0.2 kg	Approximate

Ranges are indicative industry figures for RFQ preparation, not a supplier commitment. Confirm every value and standard with the legal manufacturer before ordering.

Components / BOM

Forced-Guided Contacts
Mechanically linked contacts that ensure if one contact welds shut, the opposing contact cannot close, maintaining a safe state.

Material: Silver Alloy, Thermoplastic
Monitoring Circuit
Internal electronic circuit that continuously checks for faults in the input signals and the relay's own operation.

Material: Printed Circuit Board, Electronic Components
Reset Circuit Part
Circuit requiring manual activation (via a reset button) to re-energize outputs after a safety shutdown or fault.

Material: Push Button, Electrical Contacts

Applied To / Applications

This component is essential for the following industrial systems and equipment:

Safety Interlock Circuit

View system integration details

Interlock Control Module

View system integration details

Manufacturers of Safety Relay

6 companies list this product among what they make. Company figures are quoted from each company's own website; every card states where the relationship came from.

DEGSON

Zhejiang, CN

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