Technical Support:Reed Switch Modification/Packaging/ Expoxy Encapsulation/Wire Bonding MKA Reed Switch MKA-50202     Description

Total Length   80 mm Glass Length   50 mm Glass Diameter 5.4 mm Contact Form   1A  (SPST-NO) Contact Position SYM Contact Material Mo Contact Rating  250W Max. Switching Voltage 250VDC / VAC Max. Switching Current 5A Contact Resistance(at initial value) 150mOhms Pull In Value (AT)  50-100 Drop Out Value (AT) 20 Operation Time  2.0 mSec.(Max.) Release Time  1.0 mSec.(Max.) Breakdown Voltage  700VDC Contact Capacitance 1.0 pF Insulation Resistance 109 Ohms Resonant Frequency  0.7 kHz Operation Temperature -60°C~+100°C High Humidity  98% (Max.) Operation Frequency 5 Hz Electrical Life  105(250V,1A) Test Coil       5000  335 Ohm  

Order informations 

MPQ/MOQ: 1K

                                                   Reed Switch Structure and Principle of Operation

The reed switches comprise two ferromagnetic reeds placed with a gap in between and hermetically sealed in a glass tube. The glass tube is filled with inert gas to prevent the activation of the contacts. The surfaces of the reed contacts are plated with rhodium or iridium.

The reed switch is operated by the magnetic field of an energized coil or a permanent magnet which induces north (N) and south (S) poles on the reeds. The reed contacts are closed by this magnetic attractive force. When the magnetic field is removed, the reed elasticity causes the contacts to open the circuit.

The transfer type reed switch is normally ON, due to mechanical bias of the common (COM) lead, which is between the normally closed (N.C) reed contact and the normally open (N.O) reed contacts.

When an external magnetic field is induced, the N.C blade is not affected because it is non-magnetic but the COM lead is attracted by the N.O lead and moves. When the magnetic field is removed, COM lead again moves to the N.C lead by mechanical.

                                                                

MKA Reed Switch MKA-50202