A broad portfolio of products and the basis for new developments – for fire protection, HVAC, instrumentation & control, OEM partners, planners and architects.

Product Finder


Customer-specific developments and innovative relays for metering, energy management, automotive and e-mobility.

Product Finder


Made-to-measure developments and innovative solutions: Your contact to the custom-fit solenoid


Innovation with quality – Gruner relays

Latching relays from Gruner are individually developed solutions that set global standards and that are frequently specified by the industry. Today, Gruner is one of the last independent manufacturers of relays in Germany, and it is the undisputed technology leader and world market leader for latching relays in the energy management sector. ’Innovation, not imitation’ is our motto for delivering relays to the market and to applications.

Innovation and qualityThe global leader for metering

Even smaller but just as powerful. The Gruner 726 relay is a consistent further development of the 700 series. With its superlative properties and the ‘shared-design’ principle, the 700 series of polarised latching relays covers a diverse range of energy management functions. These include load management, tariff switching, disconnect-reconnect applications and prepayment.

  • Great switching power with minimal power consumption
  • Great switching reliability and optimised service life
  • Great reliability with a minimum of mechanical components
  • Exceptionally wide range of switching powers

Technical specifications and information about the Gruner 700 series of relays:

Product Finder

Gruner 48 Volt relays48V – achieved economically

The Gruner 850 relay is the first relay for 48V applications in the automotive sector.

With the 852 relay, the 2nd generation of 48V relays is now available. 48V technology is used primarily in mild-hybrid vehicles for the management of lithium ion batteries. Due to their higher voltage, many functions in vehicles can be electrified without the additional weight of an extra battery. This enables the size of the engine to be reduced, which cuts down on CO2emissions.

The 852 relay is characterised by a higher level of power capacity. Here, a small controllable electronic unit is also integrated, together with an option for measuring and reading out the temperature on the contacts. 48V technology (MHEV) offers a cost benefit across the board: compared to plug-in-hybrids (PHEV) or fully electric vehicles (BEV), the system costs are relatively low.

Technical specifications and information about the Gruner 850 and 852 relays:

Product Finder

Gruner 800 relayFor charging and storage

Plug-in hybrids and electric vehicles frequently get charged at wall charging stations, known as ’wall boxes’. Gruner developed its 4-pin 800 relay specifically for the charging & storage sector. It acts as an isolating relay in wall boxes up to 22 kW. It serves as an isolating relay in wallboxes up to 22kw, and can also withstand overcurrents up to 3,000A.

Technical specifications and information about the Gruner 800 relay:

Product Finder

Gruner relaysFor the dual-voltage vehicle electrical system

Since 2016, cars have had dual-voltage vehicle circuits because the 12V system that was common until then was no longer able to cover the energy requirements of an ever greater number of assistance and safety systems as well as comfort functions. However, this new 48V technology presents challenging requirements to automotive electronics.

The previously used 12V relays are still required to switch the battery power supply, or to switch various areas of the vehicle circuit on and off, because despite the higher voltages now present in a vehicle, there is still a need for a 12V vehicle circuit.

Product Finder

Without an inert gas fillThree times as economical

The galvanic isolation of power circuit and load circuit is crucially necessary to separate the potential safely in the event of a malfunction or a road traffic accident. For this purpose, the market has so far turned to isolating elements from the high-voltage sector. This is because, on a 48V vehicle circuit, switch arcs constitute a problem. The high electronic potential could prevent a switch arc from being extinguished automatically, which could in turn cause damage to the vehicle or the relay. Relays for the 400 VDC sector have a very costly inert gas fill to suppress the ignition of arcs. Each relay has a permanent magnet inside, which is supposed to expand the arc with its field and to extinguish it. This is why Gruner has developed a relay specifically for the 48V vehicle circuit, allowing this expensive and cumbersome design to be circumvented.

Shock-resistantWith high resistance to short-circuits

The 48V relay functions without a gas fill or magnetic suppression fixtures. Instead of this, defined contact distances and their fast, temperature-dependent opening speed ensures that the arc is extinguished. The contact module is based on a symmetrical design so that the direction of current flow is not an issue. This enables the relay to be used more flexibly than many other high-voltage devices. In addition, the contact position can be sensed. Using a separate sensor request, it is possible to establish if the relay is open or closed. The diagnosis potential can be sensed at several points on the contact assembly. This makes it possible to determine quickly and reliably whether a fault is present.

Compact designEfficient and easy to adapt

The Gruner 48V relay is characterised by a very flexible design. For example, the adjustment of coil adaptation is very simple because the entire relay remains the same, and only the connector adapters are replaced. In addition, the relay only weighs 130 g instead of the 400 g that are common on conventional high-voltage relays. It is characterised by a flat and compact design, and it also saves on space in the battery or in the vehicle. In addition, the compact shape of the 48V relay and its ease of integration make it three times more economical than conventional components from the high-voltage sector.


PDF for download

Innovation, not imitation

Develop new, continue developing

Thanks to superlative performance levels and many specially developed features, Gruner relays are suitable for a wide range of applications: ripple control receivers and soft-start motors, load management, prepayment, automotive battery management or in charging pillars for e-vehicles.

High degree of vertical integration, high quality

Our many years of experience, our high level of vertical integration, intelligent test systems to accompany production and our high degree of flexibility have all helped to make us one of the innovation drivers and quality providers in the relay sector.

Reliably flexible

Gruner believes in taking the short route from A to B. This is the only way to adapt designs quickly. 100% quality and the development of genuine innovations are not mutual exclusives. We have proven that by becoming the world market leader for polarised latching relays from 8 to 200 amperes.

Customer orientation – in demand internationally

We convince through performance. And through value for money. We develop solutions for our customers from which they benefit, and that help them to progress. Our relays reduce power consumption, increase safety, save time and costs – and are definitely suitable for your application.


November, 15. - 18. 2022

Visit us at the leading trade fair for battery technology and learn more first-hand about the benefits that you can leverage with our relays in the battery, electro and hybrid sectors.

More about relays from Gruner

Are you looking for relays to get you further ahead? If so, then take a look at our product range. Are you looking for a bespoke solution or for a professional point of contact for your application? Then send us an e-mail.


Bürglestr. 15 - 17
78564 Wehingen

Phone: +49 74 26 / 948-0
Fax: +49 74 26 / 948-200