LIGHT FOR A MINUTE

LIGHT ON MOMENTDue to the constant rising costs of utilities, including electricity becomes relevant and economical expenditure. Electric lighting in non-residential premises (e.g., closets, utility rooms, etc.) required most often for a minute or two to take out something you need or Vice versa — to put for safekeeping. But to turn off the lights often forget, and the bulb continues to burn without the need sometimes until the next visit of the premises.

 
The proposed device is a time switch that turns on the light for 1 — 1.5 minutes, and then it automatically extinguishes.
 
The device is connected in parallel to the regular light switch (SA) and in standby mode consumes virtually no power.
 
The figure shows the electrical circuit of the time relay. It contains: two transistor — VT1 and VT2 (КТ315Г), timing capacitor C1 and a resistor R2, a parametric stabilizer VD1 (КС168), optothyristor VS1 (ТО125-12,5), the control button SV1, two current-limiting resistors R1 and RZ, and others.
The device is simple. At the time of first switching it on, the button BB1 capacitor C1 is discharged, and therefore the charging current is supplied to the base of the compound emitter follower. Both transistors are opened. In the circuit of the emitter of the transistor VT2 turns on the led which is inside of optothyristor. The led activates the thyristor. Lamp illuminates.
 
Schematic diagram of the time switch included in the lighting circuit auxiliary (non-residential) premises
 
Schematic diagram of the time switch included in the lighting circuit auxiliary (non-residential) premises
 
Electric lamp with the device briefly turn the light on and two buttons with wires for a long utility room
 
Electric lamp with the device briefly turn the light on and two buttons with wires for a long utility room
 
After a time determined by the values of capacitor C1 and resistance of resistor R2, the transistors are closed. The light goes out. Re-enable the secondary light button blower SB. The capacitor is discharged. The pass-through charge current opens the transistor, and they have optothyristor. The light again illuminates.
 
For convenience, for example, in the long room of the control buttons blower SB can be two or more.
 
For long-time lighting is used, as usual, the full-time switch SA.
 
A. PARTIN, L. MARTINA, Ekaterinburg

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