Momentary pushbuttons MB series

For remote control of electrical units and machines, various control buttons and push-button stations are often used. Most often, these tools are used to control equipment that uses electric motors as drives.

A button is an electric command device, consisting of a button (contact) and drive elements, and intended (mainly) for manual remote control of electromagnetic devices.

All button controls can be divided into two large groups - buttons with latching and buttons without latching. The latter are also called "instant action" buttons. The principle of operation of buttons with fixation is quite simple. When the button is pressed, the state of the contacts changes - the circuit either closes or opens. In this case, the button is fixed in the “pressed” position, preserving the state of the contacts. In the simplest case, they pressed the button - the light came on. And the light will continue to “burn” until the button is pressed again.

For non-latching buttons, the process will be slightly different. When the button is pressed, the state of the contacts changes, and it will be saved as long as the button is pressed. At first glance, it is not very convenient to keep the button pressed as long as there is a need to supply power (or power failure) to the generating set. However, there are a number of areas of application when such an algorithm of actions is really needed. For example, gate opening/closing control, roller shutter control, etc. At the same time, it becomes possible not only to open / close the gates and blinds, but also to partially open them. The drive motor will control the opening/closing of the gate as long as the button is pressed.

But it should be borne in mind that the use of push buttons has a number of limitations. For example, to control electrical units with high current consumption. In such situations, the use of buttons with fixation becomes not entirely appropriate due to the burnout of their contacts under the influence of high currents. In addition, there is also the possibility of interference on sensitive parts of the circuit. For example, the control button is located on the front panel of the case, and the power wire to it runs along the sensitive sections of the circuit.

A way out of such situations can be found by using a button without fixing for a small current together with a pulse relay. In this case, the resource of the button increases, since the current in the control circuit is much less than in the power circuit of the unit. And switching power directly to the electric device is carried out using a pulse relay. Such a scheme works like using a button with a fixation. Briefly pressing the button - the unit is powered. And after releasing the button, the unit continues to work. To turn it off, briefly press the button again.

Typical scheme for using a momentary button and an impulse relay

Pushbuttons of the MB series manufactured by EMAS are produced in a standardized housing designed for panel mounting in a hole with a diameter of 22mm. The buttons can have the following contact groups - 1NO , 2NO , 1NO / 1NC , 1NC , 2NC , which allows them to be used for solving almost any task.

Button dimensions

Main technical parameters

• Operating voltage 240VAC;
• Working current 4A;
• Operating temperature range -5…+40°S;
• Degree of protection IP50;
• Electric resource not less than 100,000 operations;
• Mechanical life of at least 500,000 operations;
• Operating frequency of operations 1200/3000 operations per hour.

Button color and operation algorithm