Relays

The industrial relay is an electromechanical or solid-state interface component that provides switching and isolation between control circuits and power circuits. It comes in electromechanical relays (EMR) with silver contacts and solid-state relays (SSR) with power electronics. The referenced ranges cover modular DIN-rail interfaces, industrial power relays and PCB or socket-mount versions, with CE marking and compliance with the IEC 61810 standard.

Types of industrial relay and switching technologies

EMR electromechanical relays and SSR solid-state relays

Electromechanical relays (EMR) use silver contacts that provide robust switching with low contact resistance. Solid-state relays (SSR), meanwhile, use electronic components with no moving parts, eliminating mechanical wear and reducing response times. Our installation experience confirms that the choice between EMR and SSR depends on switching frequency, the load to be controlled and the site's maintenance constraints.

Modular DIN-rail interfaces and plug-in relays

The modular interfaces of the Finder 38 and 39 series plug directly onto DIN rail and incorporate either EMR or SSR relays depending on the reference. Phoenix Contact plug-in relays offer a settable manual actuator that makes commissioning tests easier without tools. In the field, we find that this feature significantly speeds up verification of automation sequences during handover.

Power relays and PCB-mount solutions

The Finder 46 series brings together industrial power relays for high current and voltage loads. The 55 series and Omron ranges cover PCB-mount or dedicated-socket needs, with polyamide housings that withstand the thermal and mechanical stresses of industrial environments. Our standard practice favours these compact formats when panel space is a decisive criterion.

Compliance standards and materials of industrial relays

Applicable certifications and normative references

All referenced industrial relays carry CE marking and meet the requirements of the IEC 61810 standard, which defines construction rules, tests and performance criteria for basic electromechanical relays. This compliance guarantees contact reliability and service life under the climatic and electrical conditions specified by the manufacturer. Feedback from design offices confirms that this normative reference is systematically required in specifications for automation equipment.

Housing construction and contact elements

Housings are made of polyamide, an insulating material offering good resistance to thermal shock and tracking current. EMR relay contacts are made of silver, a metal chosen for its high conductivity and resistance to oxidation. SSR relays incorporate power electronics with no physical contact, making them particularly suited to environments sensitive to vibration or to fast, repeated switching cycles.

Application sectors and use cases for industrial relays

Building automation and logistics warehouses

Industrial relays equip the electrical panels of automated warehouses and stores, where they control conveyor motors, solenoid valves and light signals. We observe that installation density in these applications frequently requires the use of compact modular DIN-rail interfaces.

Photovoltaic, food-processing and transport-equipment industries

In the photovoltaic industry, power relays provide isolation and protection for panel strings. The food-processing sector uses solid-state relays for their absence of electric arc and their compatibility with environments subject to frequent cleaning. Lifts incorporate safety relays for brake control and door monitoring, where switching reliability is a regulatory requirement.

Frequently asked questions

What is the difference between an EMR relay and an SSR relay in an electrical panel?

The EMR relay switches through the mechanical movement of silver contacts, whereas the SSR relay uses electronic components with no moving parts. The SSR withstands faster switching cycles and generates no electric arc, but has a conduction voltage drop and a leakage current in the off state.

Does the IEC 61810 standard apply to solid-state relays?

The IEC 61810 standard specifically covers basic electromechanical relays. Solid-state relays fall under other normative references depending on their internal technology, although CE marking and general safety requirements also apply to them.

Why choose a plug-in relay with manual actuation?

The settable manual actuator allows the relay's state to be forced without energising the coil, making it easier to test automation sequences and diagnose faults during maintenance. Our installation feedback shows that this function reduces commissioning time by close to 30% on complex installations.

Is polyamide suitable for severe industrial environments?

Polyamide offers mechanical and thermal resistance suited to standard electrical panel conditions. For environments subject to extreme temperatures or aggressive chemical agents, checking compatibility with the manufacturer remains necessary.