The relay is an electrical device intended for switching electrical circuits (jumping the output variables) for specified changes in electrical or non-electrical input quantities.
Electromagnetic relays, thanks to a simple principle of operation and high reliability, have received the widest application in automation systems and in electrical protection circuits. Electromagnetic relays are divided into DC and AC relays. DC relays are divided into neutral and polarized. Neutral relays respond equally to the direct current of both directions flowing through its winding, and polarized relays respond to the polarity of the control signal.
The work of electromagnetic relays is based on the use of electromagnetic forces that arise in a metal core as the current passes through the coils of its coil.
The relay unit is a load-bearing structure designed to accommodate relays and other products and ensure their stability and strength under specified conditions.
The TN VED code of the EAES: 8535; 8536; 8538
JCPS 2: 27.90.70.000
Components (nodes): Electromagnetic relays consist of the following main parts: coil, electromagnet, armature, fixed contacts, resistor, etc.
Normative documents: These devices must comply with the requirements of clauses 5b, 7, 12, 16, 24a, 24b of Article 4 of the technical regulations of the Customs Union TR CU 003/2011 “On the safety of the railway transport infrastructure”. They are manufactured in accordance with the requirements of GOST 32668-2014 “Relays of safety, relay blocks and cabinets. General specifications. “
Recommended circuits for certification of electromagnetic relays:
The cost of works on the certification of electromagnetic uncontrolled relays of the first reliability class, relay units is made up of the cost of the main certification work, as well as tests of selected samples of a certain type. And it depends on the certification scheme chosen by the applicant.