Relay series MKU-48

Relays of the MKU series are designed to work in DC and AC circuits with a voltage of up to 220 V. The coil of the relay withstands 110% for a long time UNo. At direct current, the maximum interrupting current at a non-inductive load and voltage 220 V is 1 A, at 110 V — 5 A. The maximum interrupting current at an inductive load and voltage 220 V is 0.5 A, at 110 V — 4 A. At alternating current the maximum interrupting current at a voltage of 220 V is 5 A, at 110 V — 10 A.

Relays of the MKU-48 series (Fig. 1) work reliably at a current or voltage of no more than 80% and alternating current at a current or conjugation equal to 85% of the nominal value. The power consumption of the DC relay is no more than 3W, and the AC relay with the armature pulled is no more than 5VA for MKU48s.

The interrupted power of the contacts in a DC circuit at a voltage of up to 220 A with an inductive load without spark extinction will be 50 W, in an AC circuit at a voltage of up to 220 V — 500 VA.

The long-term permissible current through closed contacts, both alternating and direct, is 3 A.

Rice. 1.The design of the MKU-48 relay: 1 — magnetic circuit, 2 — coil, 3 — armature, 4 — moving contacts, 5 — fixed contacts, 6 — return spring, 7 — screw for tensioning the return spring, 8 — armature limiter , 9 — tension springs, 10 — axis of the armature, 11 — copper gasket of the armature, 12 — insulating frame for closing contacts, 13 — insulating gaskets, 14 — screws for assembling contacts

Unlike other relays, the isolation of the live parts of the MKU-48s relay from the magnetic circuit withstands a voltage of 1500 V.

The frame of the relay coil is made of plastic and allows the placement of one independent coil. Relays are produced in housing and without housing. When installing several relays in a common housing, in order to reduce mutual heating, it is recommended to install them at a distance of at least 20 mm from each other.

The maximum number of contact springs installed on the relay is 16 for the MKU-48 relay without a box and 8 for the MKU-48 and MKU-48 relays in the box.

Under normal conditions, the MKU-48 and MKU-48T relays can withstand 1 million operations under load, and the MKU-48 relays - 100 thousand operations, after which contact pressures and clearances are allowed to change by + 30% of the initial ones.

The response time of the relay with normal contact adjustment and rated voltage is not more than 35 ms for a relay with eight contact springs and not more than 60 ms for a relay with sixteen contact springs.