In the machine- and plantbuilding sector the safety becomes more and more important. Everywhere, safety modules and also safety control systems are used.
Despite the increasing use of semiconductor relays, the electromechanical relays are still an important part.
Here these special relays find their application.
The safety relays or relays with positive guided contacts have at least one normally closed contact and one normally open contact. The normally closed contact and the normally open contact are never closed together.
Also the relay has to guarantee during its life a contact distance of 0,5 mm in operation and also in case of failure.
Due to this feature a primary monitoring function identifies if a contact breaks down.
Eg.: If a normally open contact is welded the corresponding normally closed contact is not able to close when switching off the supply voltage.
emergency stop modules
safety gate monitoring
two- hand controls
Sockets for the PCB mouning are available for mostly all safety relays. This allows a fast exchange between the relays at preventive machine care which is often prescribed regularly (eg power station) or in case of service. We provice sockets for DIN- rail mounting.
Customer- specific solutions
We are able to realise customer- specific solutions very fast due to a high production depth here in Furtwangen. We can supply relays with mixed contact types and materials.
Two different types of safety relays are available:
type A: all contacts are connected mechanically
type B: relays which have mechanic connected contacts as well as non- mechanic connected contacts. Also change- over contacts belong to this.
All Dold safety relays correspond to the actual standards.
DIN EN 61810 basic relays
DIN EN 60255 electrical relays
DIN EN 50205 relays with positive guided contacts
DIN IEC 60664 insulation coordination for electrical equipment in low voltage systems
PCB relays from E. Dold & Söhne KG are available with 2,4,6 and 8 contacts, in upright or flat version, from 5A up to 10A, in sensitive version (extra low coil power), with AgSnO 2,AgNi 10 or AgNi 0,15 +5 µm gold plated contacts.
Emergency Stop Modules
Emergency stop modules with semiconductor output are checking periodical the outputs by switching off the output voltage. Controls, frequency converters or servo drives note this and switch off. This is not necessary with emergency stop modules or safety relays from Dold. Therefore, a trouble- free working is guaranteed. In addition, the emergency stop modules have potential free outputs and in most cases contactors wont be used anymore for higher loads.
In lift controls Dold safety relays provide that the lift starts only when doors are closed.
Dold safety relays build a safe and reliable interface between control level and periphery so that the trains do not stop on free road.
Safety relays all Safety relays are aviable with the following contact materials : AgNi10; AgNi0,15 +5um Au; AgSnO2.
Also mixed contacts are possible!