Power On Delay Circuit | Electronic Project Circuits

Posts Tagged ‘power on delay circuit’

Delay switch turn on the monitor

This is a time delay switch on the monitor. The contacts of the relay acts as a switch.The contacts of the relay, acting as a switch.When entering into the 220volt mains. Circuit delay for a while. To reduce current surges, gradually flowing into it, over time.
The resistor R1 and capacitor C1, C2, it allows current to flow into the circuit, only about 40 milliamps. It has a voltage zener diode ZD1 limited to a 15 volt, and through the rectifier diode D1, diode D2 coupling a bias voltage to the transistor Q1, and a drive current to the relay RY1. Switch contacts touch each other next to the main 220 volt and monitor.
The C4 capacitor current to transistor Q1.The half negative phase AC power, because the voltage across rectifier D1 is only half the positive side only. This circuit, transistors must work all the time, while using the device. So, connect the C4. The filter’s capacitor C3 flows smoothly. Diode D3 prevents reverse voltage from the coil of the relay, which can cause circuit damage.

Be the first to comment - What do you think? Posted by admin - June 28, 2011 at 5:21 am

Categories: Electronic Control Tags: monitor controls circuit, power on delay circuit

Simple Delay turn on the monitor

Currently we use the same computer. Most are connected to an outlet with a switch to turn off with the easier to use. But when we turn off the switch, plug it in short strokes will be.Surge current flows into. This may result in damage and lost a hard drive. Therefore require a delay for a while. It is time to turn on itself, which will help prevent hard disk the damage.
This circuit can be used with 220 volt house power. by contact of the relay switch to acting. When 220-volt power input to circuit, the lower the voltage to 220 volts to 15 Volts, with R1, R2, C1 and C2 current limiting it to about 41 milliamps. and C Partners diodes ZD1 limited pressure it to 15 volt and Direct Optical Fire through D1,. D2 and C3 to the party circuit.
There will be current through R3 to charge C4, which takes time to charge and when the C4 charge fully to make a current flowing into pin B of Q1. the Q1 runs and drive currents to RY1 switch contacts touch. Each per 220-volt power to the monitor acts C4 delay. If you want a long delay, it added the C4, but if you want to delay it a little to reduce the C4.

Be the first to comment - What do you think? Posted by admin - December 20, 2010 at 12:02 am

Categories: Electronic Control, Monitor Tags: ac power monitor, computer automatic control, power on delay circuit

Delay to supply voltage for surge protector by scr

Power source that, when connected to an external circuit, and now will turn to a current surge.Power supply is a high voltage surges.External circuit therefore damage.Which can solve this problem with the delay to a power source.When supply switches.Delay circuit to work, the delay occurred during the current surge.Then connected to a power source as usual.
Operation of the circuit be When a power supply to the Supply voltage in.Delay circuit will start by Delay depending on the charge of C1 is growing.
So take some time to be full.When C1 is fully charged will allow the current to flow through ZD1 zener diode 6 volt.This will limit the voltage at the trigger pin to G (gate) of the SCR.The aforesaid conduct of the SCR Supply voltage to output Delayed supply out.