10‘‘ colour touchscreen: 1805 & 1886 series
Modern digital technology for safety-current-limited applications or those at 500 VA / 200 mA.
Relays are needed everywhere in technology. It is especially difficult to find suitable switches when frequencies, voltages and currents lie beyond the typical levels. That is why SPS electronic offers special relays for this use. More than 3 decades of experience in high-voltage technology form the basis for the development of our products.
In technology, an electro-mechanical relay cannot be completely replaced by an electronic switch. The main argument is the electrical isolation of the lines that are to be opened. That is not given for electrical switches. A further, essential point is the safe isolation of lines. Contingent on the electro-mechanical concept, it can be ensured that the relay is not switched without excitation voltage. In the case of electronic switches such as transistors or thyristors, the component can be defective through an overload and cause a short-circuit. That is an absolute no-go for safety-relevant switching circuits.
An alternative, albeit not a very good one, are reed relays. This technical concept may be cheaper but cannot replace an electro-magnetic relay. Through the setup of the reed relay, the reed contact
has to open “on its own”. As a consequence, these relays often get “stuck” and can no longer open. Here too, this is an absolute no-go for numerous applications. Also due to the functional principle of the reed relay, these switches can only switch low currents. That significantly limits the applications. So reed relays are no alternative for a lot of applications.
Last but not least, vacuum relays are offered on the market. This technology builds on the principle that merely little gaps are needed in an airless space for the isolation. Noble gases are often used too. Due to the gas-tight glass containers, the relays are quite expensive and only available for low currents. So also not an alternative to the electro-mechanical relays by SPS electronic.