J.DARBYSHIRE & SON LTD

COUNTERS - TIMERS
ENCODERS - RESOLVERS
SAFETY RELAY SOLUTIONS
PROCESS CONTROLLERS
VACUUM CONTACTORS & STARTERS

Relays

Our Hengstler and Kaco brands are world leaders in offering relays for switching currents between 10mA and 100A, relays with forcibly guided contacts to EN50205, conforming with RoHS and REACH regulations, and special-purpose relays of many different kinds. Our large international customer base benefits from many years of experience. In controller and medical technology, in energy management, and in laboratory environments, there are numerous Hengstler relays available and in use worldwide.

Safety Relays

HENGSTLER safety relays, i.e. relays with forcibly guided contacts to EN 50205, are used wherever people and high-quality products are to be protected against potentially hazardous machine movements. If, for any reason, a relay should fail, e.g. due to a melted relay contact, the second, redundant, relay can still be used to close the installation down safely. A principle of these captive contact is that, after the installation has been closed down, it cannot be simply restarted and a potentially hazardous situation for people and machines is effectively prevented.

The special functionality of positive guided contacts is achieved by ensuring the contacts are mechanically linked together so that it is impossible for the NO (normally open) and NC (normally closed) contacts to be closed at the same time. The contacts are linked so that no one contact in a relay can change state without changing all the contacts in that relay. If e.g. one NO contact fails because it has melted or jammed, the corresponding NCC remains open. This ensures that the installation or machine cannot simply be restarted because of the open NC contact.

Bistable Relays

Bistable relays by HENGSTLER are used wherever short control pulses have to switch large currents on and off. The specially designed drive system using an H-armature enables the relay to switch from one state to the other as a result of only a short coil pulse. Thanks to the high permanent magnet holding forces, bistable relays are extremely resistant to vibrations and impacts.

High Voltage Relays

HENGSTLER's high-voltage relays are used wherever voltages up to 5,000 V have to be safely and reliably switched on and off. It is possible not only to feed high (test) voltages through the relay, but also, due to the maximum switching current of 10 A, the load can also be switched and made operational through the relay contact.

Power Relays

The classic application for HENGSTLER power relays is in linking control logic with the switching load. Due to the fact that the relay drive is electrically isolated from the contact side, the control voltage (extra low voltage ELV) is effectively completely separate from the voltage for the switching load (low voltage LV). Depending on the specific application, many different variants of relays with different numbers of contacts, contact materials and connections are available.

Mains Isolation Relays

HENGSTLER mains isolation relays are used wherever appliances and installations have to be shut down by disconnecting both poles. This kind of isolation from the LV mains, termed "full disconnection", is achieved with a contact gap of von > 3 mm (basic isolation).