Relay Control

LIGHT_BEAM_OPERATED_ON_OFF_RELAY

Published:2009/6/24 23:50:00 Author:May

When a beam of light strikes the photocell, the voltage across neon lamp NE-1 rises sharply. NE-1 turns on and fires the SCR. K1 is an impulse relay whose contacts stay in position even after coil current is removed. The first impulse opens K1's contacts, the second impulse closes them, etc.   (View)

View full Circuit Diagram | Comments | Reading(885)

LIGHT_ISOLATED_SOLID_STATE_POWER_RELAY_CIRCUITS

Published:2009/6/24 23:48:00 Author:May

Both circuits use the G.E. SC146B, 200 V, 10 A Triac as load current contacts. These triacs are triggered by normal SBS (2N4992) trigger circuits, which are controlled by the photo-Darlington, acting through the DA806 bridge as an ac photo switch. To operate the relays at other line voltages the asterisked (*) components are scaled to supply identical current. Ratings must be changed as required.Incandescent lamps may be used in place of the light emitting diodes, if desired.   (View)

View full Circuit Diagram | Comments | Reading(1537)

CAPACITANCE_RELAY

Published:2009/6/24 22:54:00 Author:May

Capacitor C1 and body capacitance (C2) of the operator form the voltage divider from the hot side of the ac line to ground. The voltage across C1 is determined by the ratio of C1 to C2. The higher voltage is developed across the smaller capacitor. When no one is close to the touch button, C2 is smaller than C1. When a hand is brought close to the button, C2 is many times larger than C1 and the major portion of the line voltage appears across C1. This vol-tage fires the neon lamp, C1 and C2 discharge through the SCR gate, causing it to trigger and pass current through the load. The sensitivity of the circuit depends on the area of the touch plate. When the area is large enough, the cir-cuit responds to the proximity of an object rather than to touch. C1 may be made variable so sensitivity can be adjusted.   (View)

View full Circuit Diagram | Comments | Reading(823)

TRANSISTOR_RELAY_DRIVER

Published:2009/6/24 5:37:00 Author:May

An input of 4 V or greater will drive this relay circuit.   (View)

View full Circuit Diagram | Comments | Reading(0)

LATCHING_RELAY_DRIVER

Published:2009/6/24 5:37:00 Author:May

An input of 4 V or greater will drive this circuit. When the relay pulls in, one pair of contacts is used to latch the relay closed. It will remain closed until S1 is pressed.   (View)

View full Circuit Diagram | Comments | Reading(0)

HIGH_MPEDANCE_RELAY_DRIVER

Published:2009/6/24 5:35:00 Author:May

A CMOS gate is used to drive a switching transistor and relay.   (View)

View full Circuit Diagram | Comments | Reading(0)

LATCHING_RELAY_DRIVER_FOR＋12_V_LOADS

Published:2009/6/24 5:33:00 Author:May

A 4-V signal will cause the relay to pull in when Q1 turns on. Latching is obtained by feedback through a 4.7-kΩ resistor. A switch is used to select latching or nonlatching operation. A NO pushbutton releases the circuit.   (View)

View full Circuit Diagram | Comments | Reading(0)

MOMENTARY_RELAY_CIRCUIT

Published:2009/6/24 5:33:00 Author:May

The charging current of a capacitor can be used if a momentary relay-on circuit is needed Depending fin the relay characteristics，C will vary from 1000 to 4000 μF or so for a 1-s hold time if a 500－Ω relay is used.RD discharges capacitor C to reads，the circuit for the next oPeration The valueshould be high enoughso as notto maintian the relay closure at highest expected supply voltage．   (View)

View full Circuit Diagram | Comments | Reading(2782)

IMPROVED_THERMOSTATIC_RELAY_CIRCUIT

Published:2009/6/24 4:24:00 Author:May

  (View)

View full Circuit Diagram | Comments | Reading(564)

PROGRAMMABLE_LIGHT_ACTIVATED_RELAY

Published:2009/6/22 22:47:00 Author:May

Digital inputs A, B, C, D select different light levels by varying the value of bridge circuit resis-tance R4.IC1 741 op ampIC2 CD4066 quad bilateral switchQ1 NPN transistor (2N2222, 2N3904, or similar) D1 diode (1N4002, or similar)C1 0.1-μF capacitorR1 photoresistorR2, R3 390-kΩ, 1/4-W 5% resistorR4, R5 1-MΩ, 1/4-W 5% resistorR6 820-kΩ, 1/4-W 5% resistorR7 470-kΩ, 1/4-W 5% resistorR8 270-kΩ, 1/4-W 5% resistorR9 100-kΩ, 1/4-W 5% resistorK1 relay to suit load   (View)

View full Circuit Diagram | Comments | Reading(0)

TV_REMOTE_CONTROL_RELAY

Published:2009/6/19 4:06:00 Author:May

This circuit functions as an IR repeater to extend the range of your TV remote control. MOD1 is a P/N GP1U52X IR detector and the receiver is available as Radio Shack P/N 276-137.   (View)

View full Circuit Diagram | Comments | Reading(2482)

SENSOR_ACTIVATED_RELAY_PULSER

Published:2009/6/17 22:46:00 Author:May

A sensor turns on Q1 to activate the low-frequency 555 oscillator, which pulses LAMP I1. Sensor may be sensitive to changes in light or temperature.   (View)

View full Circuit Diagram | Comments | Reading(625)

TIME_DELAY_RELAY_

Published:2009/6/17 22:45:00 Author:May

Using a 4060 CMOS binary divider and built-in clock oscillator, a long-duration timer can be made very simply. The solid-state relay can be sized for your application, and can be replaced with a mechanical relay if a suitable power supply is available. With the components shown, a 4.5-Hz clock frequency is generated. Divided outputs are available from÷ 4 to 16384 (about 4 hours).   (View)

View full Circuit Diagram | Comments | Reading(4579)

SOLID_STATE_RELAY_CIRCUITS

Published:2009/6/17 22:41:00 Author:May

This dark-activated relay switch can be used to turn on walkway or other outdoor lighting at dusk. By using alternate connections to A and B, increasing illumination, high and low temperatures can be sensed.   (View)

View full Circuit Diagram | Comments | Reading(1111)

SOLID_STATE_RELAY_CIRCUIT

Published:2009/6/17 22:39:00 Author:May

R1 limits input current while Q1 acts as a current sink to protect IC1. D1 serves as a polarity pro-tector. IC1 provides a trihc output to trigger the main triac, TR1.   (View)

View full Circuit Diagram | Comments | Reading(1850)

SOLID_STATE_LATCHING_RELAY

Published:2009/6/17 22:38:00 Author:May

This simple circuit provides a solid-state equivalent of the electromechanical latching relay (see the figure). What's more, the switching is clean, highly resistant to vibration and shock, and isn't sen-sitive to magnetic fields or position.The circuit operates as follows: a set pulse to the 4043 RS latch takes its output high and turn on the 2N3904 transistor. Current will then flow through the photovoltaic relay's LED and the resistance between D1 and D2 will fall from several gigaohms to less than 30 Ω. The PVR will remain in this state until a reset pulse is received by the 4043 RS latch.   (View)

View full Circuit Diagram | Comments | Reading(1767)

RELAY_FUSE_FOR_POWER_SUPPLIES

Published:2009/6/17 20:45:00 Author:May

A method of adding overload protection to a power supply using a relay is shown. In each cir-cuit, the relay must be reset by a momentary switch using a charge on capacitor C2. This prevents overload ifthe short still exists.   (View)

View full Circuit Diagram | Comments | Reading(1111)

DARK_ACTIVATED_RELAY_WITH_HYSTERESIS

Published:2009/6/17 2:32:00 Author:May

The hysteresis of a 555lC can be used to advantage for sensing a drop in light. An LDR or CDS cell with about 2 to 8 k resistance at desired light level should be used.   (View)

View full Circuit Diagram | Comments | Reading(1219)

RELAY_FUSE_FOR_BATTERY_CHARGES

Published:2009/6/17 1:53:00 Author:May

Charged capacitor C3 and momentary push-button switch S2 are used to momentarily energize relay RE2. The batte:y under charge energizes the relay to hold it closed. S2 will energize the relay even if the battery is too far discharged initially to energize it.   (View)

View full Circuit Diagram | Comments | Reading(756)

The pulse delay circuit composed of gate circuit

Published:2011/6/29 2:58:00 Author:Rebekka | Keyword: pulse delay circuit , gate circuit

Pulse delay circuit will delay the output pulse that is relative to the input pulse for some time, but it will not change the width of the pulse. The main work principle of the circuit is to use the time delay function of the circuit. It delays the input pulse for a RC time. The figure shows the pulse delay circuit composed of gate circuit.   (View)

View full Circuit Diagram | Comments | Reading(809)

Pages:3/8 12345678