Explosion-proof contact blocks BKV-1, BKV-2

Purpose

The block is intended for remote control of electric drives of machines and mechanisms in mobile and stationary plants, as well as for signaling associated with the specified electric drives or other electrical devices for the domestic market and for export.

Features

• The possibility to use as limit switch for opening, for example, in enclosures.
• The possibility to manufacture with various groups of contacts: 1NO+1NC or 2NO or 2NC.

Design

Explosionproof contact blocks of BKV type consist of a body, in which a switching device is assembled. The switching device consists of fixed contacts and a moving beam with bridge contacts installed thereon. BKV-1 blocks have two contact bridges with one normally open and one normally closed contact (1NO+1NC) or two normally closed contacts (2NC) or two normally open contacts (2NO), and BKV-2 blocks have one bridge with one normally open and one normally closed contact (1NO+1NC). With external action on the push rod, the latter will transfer the beam and switch over contacts by means of movable braces and flat springs. When the action on the push rod stops, the latter will return to the initial state. BKV-12 and BKV-22 type blocks differ from BKV-11 and BKV-21 blocks in that block bodies have a reducing bushing, which ensures explosion protection when arranged on the wall (cover) of the product enclosure, in which the block is used. The block body is connected with rivets and shall not be disassembled.

The block is made with explosion protection type “explosionproof enclosure” and protection type “е” and has single explosion protection marking ExdeIU/ExdeIICU. Blocks are intended for integration in explosion protected electrical equipment group I (for example, with explosion protection RV ExdI) and II (for example, with explosion protection 1ExdIICT6 and 2ExedIICT6).

Blocks used in group I electrical equipment are used in alternating current circuits with nominal current of up to 16 A, frequency of 50 Hz, voltage of up to 127 V and in direct current circuits with voltage of up to 110 V. Blocks used in group II electrical equipment are used in alternating current circuits with frequency of 50 Hz and voltage of up to 660 V for area 1 and up to 380 V for area 2, direct current of up to 440 V for area 1 and up to 220 V for area 2, with nominal current of up to 16 A.

BKV – Х1 Х2 V2 Х3

BKV – explosionproof contact block

Х1 – overall dimension number:

     1 – block of the first overall dimension (2 bridges): 1NC+1NO, 2NC, 2NO

     2 – block of the second overall dimension (1 bridge): 1NO+1NC

Х2 – version:

     1 – without bushing

     2 – with bushing ensuring explosion protection when arranged on the wall or cover of the product

В2 – climatic version and arrangement category according to GOST 15150.

Х3 – additional conditions* for BKV-1 according to the method of contact operation:

     1 – for 2NO (two normally open contacts)

     2 – for 2NC (two normally closed contacts)

*Note: for basic versions of blocks (1NC+1NO) – figures are not indicated.

Example of order forming:

BKV-22V2

That corresponds to:

The block with second overall dimensions with a bushing, which provides explosion protection when arranged in the wall (cover) of the enclosure of the product, with 1NC+1NO contacts.

Explosion protection marking: ExdeIU/ExdeIICU

Nominal voltage:

     alternating current (50 or 60 Hz) up to 660 V

     direct current up to 440 V

Nominal current: up to 16 A

Cross-section of connected cable cores:

     with simultaneous connection of two wires up to 2.5 mm²

     with simultaneous connection of one wire up to 4.0 mm²

Climatic version and arrangement category: V2

Operation temperature: from -60 °C to +55 °C

Level of dust and moisture protection: IР00 (the product is intended for integration into the enclosure of another product)

Number of technical conditions: TU 16-96 IMShB.642234.022 TU

Overall and connection dimensions