The device is intended to illuminate the staircase. The switch after the power supply connection (230 AT) It does not include light bulb, and expects pressing. the lamp is turned around only after pressing the button 3 minutes. If the button is pressed again, when the light is on, lamp will be turned off. Consequently, the device performs the function enable trigger / off and timer. An additional advantage is that, that one control line you can connect any number of buttons.
- On time: 3 min.
- Triggered by pressing or releasing the button.
- Nutrition: 230 VAC.
- Maximum power attached bulbs: 500 W.
- The dimensions of the printed circuit board sample: 45 × 60 mm.
Schematic diagram of the device shown in Figure 1.
The basis of the device is an integrated circuit series 4013 (eg CD4013, CD4013BE, HCF4013BE, HCF4013BM or domestic analogue 561TM2). Integrated circuit comprises two D flip-flop. One of the triggers (U1A) It operates as a Schmitt trigger. Hysteresis is provided by resistors R7, R8, and R6C2 circuit filters out any "garbage", which may appear in long wires. After clicking on the rising edge of input CLK appears trigger. This trigger operates as two counter, so each time you press the button, the output status is reversed. At rest, the output signal Q low, and the capacitor C3 is charged. Each occurrence of a high state at the output Q (leg 13) causes triac firing, and initiates a discharge process of the capacitor C3 by R9. When the input voltage zeroing (n. 10) exceeds the logical threshold, flip-flop is reset and the triac turns off. The triac control circuit may seem strange, but this method of control is optimal in this case,. How view, power supply for the positive voltage supply for the digital part (D1, C4, D3) and a negative voltage to trigger the triac (D6, C6, D4, D5). A negative voltage is much smaller, but it's enough, to open triac. When the negative output of flip-flop high, a positive voltage of the transistor based on the transistor T1, and the transistor is closed. When the voltage across branch 12 It falls to the ground level, transistor T1 opens and flows into the Triac lighting bulbs. During the model tests revealed, that by using the sensitive triac gate current with low total capacitance of C1 and C5 can be significantly reduced to 470 NF. When using standard trip triac with current> 15 mA should be used within the container 470 nF-1 uF.
Assembly and adjustment
The circuit can be assembled on the circuit board, shown in Figure 2.
This installation is not difficult. However, before the first connection to the network, you need to carefully check the correct assembly, as the system is powered directly from the mains and errors can lead to component damage. scheme, collected from functional components, immediately work properly. can be changed if necessary value C3 (1 … 4700 uF) and R9 (10 k … 4,7 MOM), to get the necessary time off.
Jumper JP1 allows you to change the switching method. JP1 is in position 1-2 and a button, attached to X1-2 and X1-3 points, activating the device when it is pressed (rice. 3), while the bridge closes the contacts 2-3, and the button is attached to connectors X1 and X1-1- 2 It allows you to turn on when the button is released (rice. 4).
The finished device must be placed in the housing, guaranteeing the safety of users. Also, be aware, and that the control cables, connected to the connector X1, and life-threatening mains voltage can occur on the buttons.