The New OMUS from Wöhner — the heat is on!

Wöhner omusAt SPS / IPC / Drives 2015 in Nuremberg, the Wöhner company from Rödental will present a completely new class of device for the control of frequent and very precise switching processes: “OMUS” — an electronic hybrid switch for resistive loads.  

The new OMUS offers unique advantages due to its hybrid technology coupled with adjustable current monitoring, integrated fuses for short-circuit protection and safe and convenient power supply based on Wöhner CrossLink® adapter technology.

Some industries, such as the plastics or food industry, employ machines in which heaters must be switched on and off very accurately and with high frequency. Current solutions for the switching of resistive loads rely on purely mechanical contacts (contactors) or semiconductor technology (solid state relays). While contactors wear extremely quickly because of the high switching frequency, solid state relays wear far less rapidly due to the semiconductor technology, but instead suffer from extremely high power dissipation. The novel “OMUS” hybrid switch from Wöhner combines the advantages of both technologies, ensuring a long life for the appliance with over 30 million switching cycles while at the same time minimising power dissipation — and all in an extremely compact 36-mm-wide housing. The new OMUS hybrid switch from Wöhner can be used in areas with up to 25A continuous current.

Hybrid technology
The device combines low-wear semiconductor technology with mechanical contacts. The OMUS performs the switching process at the ideal moment, zero volts, within a maximum time of 30ms from receipt of switching signal. During the switching process, the hybrid technology first switches the semiconductor contacts. Immediately afterwards, the parallel-guided mechanical contacts close in a non-wearing process, allowing the semiconductor contacts to reopen. This results in virtually no heat loss during the switching operation — depending on the frequency, up to 66% of waste heat can be avoided. For this reason, the OMUS hybrid switch manages without the obligatory heat sink required by conventional fast-switching processes, enabling space savings of up to 55%. The maximum switching frequency is 1Hz due to the switching sequence and to avoid excessive heating. Thanks to the hybrid technology, more than 30 million switching cycles can be achieved — about 10x more than with purely mechanical switching technology.

Design variants
OMUS on the 30Compact busbar systemIn all versions, the new OMUS allows 3 phase operation or optional switching of all 3 phases individually in a single device.

The hybrid switches compact dimensions — just 36mm wide, 160mm high and 130mm deep (144mm with busbar adapter) — can save up to 55% of cabinet space, as compared to conventional solutions with, for example, solid state relays. The device can be switched on manually and the current limits adjusted via manual operation. Further features of the new OMUS include integrated fuses which protect the device in case of short circuit and innovative measurement technology to monitor the set current values. Special CrossLink® busbar adapters enable the electronic OMUS hybrid switch to be used in both the Wöhner 30Compact and 60Classic busbar system.OMUS on the 60Classic busbar system

CrossLink® technology
Developed by Wöhner, CrossLink® Technology combines perfect shock protection with a time and space-saving latching system, which removes the need for drilling and bolting. Thanks to the special CrossLink® busbar adapters, which ensure the feed to the OMUS hybrid switch, the entire busbar system can be protected against accidental contact and remains finger-safe to IP20, even when the OMUS electronic module is removed. The adapters also allow the seamless addition of finger-protected reserve space, providing the ideal preparation for future expansion.

Come visit Wöhner at the SPS / IPC / Drives 2015 from 24 to 26 November 2015 in Hall 9, Stand 330.