Relay with turn-on delay 12 volts with your own hands. How to make a time relay with your own hands: wiring diagram. Schemes of various homemade products

Do not confuse the concept of a time relay with a fantastic time machine. Everything is much simpler here. These devices are available in our everyday life and in many industries in automatic control circuits. They are successfully used in ventilation, heating and many other management schemes.

Since there are many varieties of these devices, in this article I will try to explain the circuit and operation of a 12-volt device.

12-volt time relays are a device designed to create an autonomous time delay and provide the necessary order of the elements of the entire circuit. Most often, such devices are used to form the necessary time delays.

In the end, devices of this type are used in such cases when, for example, it is required to start a certain process not after the appearance of a command to start it, but some time after it.

Here are some indicators of such devices:

1. they must work reliably when the boost is increased from 12 to 240V (alternating current);
2. have time ranges of 1-10 seconds, 1-10 minutes and possibly 1-10-100 hours;
3. cover settings within 5-100%;
4. have at least one group of changeover contacts at the output.

There is nothing complicated in such a device, you can even assemble it yourself, without using any "intricate" and expensive parts. Such devices work like this: there is a charging capacity, the charge time of which should be determined as a result of the product of the resistance of the charging circuit and the value of this capacity itself (the charging capacitor, at this time, must be fully charged).

First of all, power is included in the circuit. After that, a capacitor comes into operation, connected through a pair of resistors and a direct conduction bipolar transistor.

When the charge is opened, the voltage across one of these resistors drops. This is due to the flow of emitter current through it. The result of this is the opening of the second transistor, which turns on the relay that controls the load circuit.

The load (in this case, a resistor and LED connected in series) starts to receive power and the LED lights up.

As the charge increases, the voltage on the capacitor plates will also rise. The charging current, in turn, will gradually fall. Together with it, the emitter current also decreases, thereby reducing the voltage at the resistor terminals. The result of this will be a decrease in the charging current of the capacitor to such an extent that the capacitor, and after it the transistor, will close. As a result, the relay will release and the LED will turn off.

To restart the device, you will need to press a button that removes the charge from the capacitor.

The time during which the relay is on is set quite simply: for this purpose, it is enough to select the values ​​​​of the resistors and the capacitor.

If the relay installed at the output of the device has several groups of contacts, then do not hesitate to use them. After all, you can find other devices that can be launched with a time delay.

Some types of these devices have several modes of operation, but additional circuit modules of the device are responsible for this.

12 schemes for the use of relays in everyday life. 2 nuances - with a delay on or off. 4 knowledge test questions. 3 best relays for ordering on aliexpress.

What is a time relay (hereinafter R.V.) with a delay

Normal relay is designed to turn on devices after receiving a signal. Time relay does not work immediately, but after the passage of a period of time specified during its manufacture or configuration. If executed with a delay, then another period is counted before switching on or off. It is also either provided in the manufacture of the device or configured (programmed).

TEST:

1. Is it possible to use a delayed relay like a regular relay?

a) No, they are completely different devices.

b) Yes, for this we set the delay to zero. (loyal)

1. Are relays with on-delay and off-delay different?

a) Yes, the former work out the delay before starting the main timer, the latter only maintain the time after the shutdown command. (loyal)

1. Is it possible to replace a relay with an off-delay with a relay with an on-delay?

a) No, they are different devices. (loyal)

1. Can a time delay relay be replaced by two conventional time relays?

a) Yes, if they are connected correctly. (loyal).

Important to know - relay with on and off delay 2 different devices

Normal time relay turns on the device mounted after them for a period of time set during configuration. Latency devices don't work that way.

OFF-delay - 1 Reverse Operated Relay

1. The relay is signaled to turn off the device.
2. The countdown of the delay time begins, after the period has expired the device turns off.

If such relay mounted in front of a conventional lamp, it will not go out immediately after the switch has tripped, but after the delay time has passed.

On-delay - 2 devices in one

1. On relay a signal is given, it turns on its mechanism or electronic circuit.
2. The delay time is immediately counted.
3. After the time has been counted, the relay turns on the connected device for the specified time.

In fact, these are two relay time connected in series.

12 ways to use a relay at home

RV connection diagram for 2 switches with a delay off 220v

OFF-delay relay it is possible to apply in order not to forget to turn off the light in the pantry or on the landing. To do this, we connect the lamp through it.

In order for the circuit to work correctly, non-latching switches must be used instead of conventional switches. Regular buttons will work too.

The scheme works as follows.

1. Entering the room, you close the switch, turning on the lighting.
2. The switch is not fixed in the closed position, then, releasing the switch key, you immediately interrupt the power supply.
3. The lighting does not turn off, the lamps are connected via OFF-delay relay.
4. The lighting will turn off only after the set time has elapsed.
5. For protection, an automatic switch is installed in front of the relay, it will de-energize the device if the current rises above the set value during a short circuit (according to PUE paragraph 7 3.1.14-19).

This scheme is convenient for long corridors. Lighting can be switched on from both sides of the room. If this possibility is not needed, then the switch can be left alone.

Option 2 - delay circuit for turning on an incandescent lamp 220v on a self-assembled relay

This scheme is suitable for those , who likes to make and is familiar with radio electronics. In it, instead of a ready-made device, designed to be powered by networks 220 volts, we use a 12 relay as it's safer. We make relay from standard electromagnetic with one contact group. Scheme alterations and appearance of the device are shown in the figure below.

The above scheme is not designed to work with a powerful load due to the limited capabilities of the contact group. If such a need arises, then an intermediate relay must be introduced. No brand difference, domestic applicable RPL, RPU-2M, RP, REP or imported (today there are more of them on the market and their price is lower, the three best relays with aliexpress we present below).

Look at the picture: a standard intermediate relay. To fit it into our circuit, we connect the contacts "N" and "A" not to the points "L" and "N", but to the points "30" and "87" in the previous diagram.

RV with turn-on delay 220v 2 more circuits for lighting control

Option 2 of the lighting control device is assembled on multifunctional digital relays.

At digital relays much more possibilities. The delay can be set not for 10 15 minutes, but for a duration of more than a day. It is possible to set the time when the light will turn on. Option 1 is suitable for controlling street lighting in a personal plot. We configure the relay to turn on at 17 o'clock and work out the delay, 13 o'clock. Street lamps will burn all night, and go out at dawn.

The device is also connected to work with two managed networks, as in the second diagram. The two channels are configured completely independently.

RV 220v on an element from Schneider or another, energy savings up to 10% for an air conditioner,

Often the air conditioner is turned on with the window open, so they run idly and waste electricity. The way out of the situation is to install the sensor on the frame sash and connect it to the power line. But this approach is also not very correct.

If you open the window for a short period of time (let the cat in), the air conditioner will turn off and then turn on again. The current consumption in the start-stop mode increases, such work also does not increase the durability of the device.

We avoid problems by installing the "sensor-switch of the air conditioner" in the circuit OFF-delay relay. The diagram is shown below.

The circuit does not even provide for a special relay with a delay; its functions are performed by an ordinary intermediate relay. It works as follows.

1. When the window is opened, the contacts are closed, voltage is applied to the relay.
2. The current required for operation is not immediately supplied to the corresponding terminals, but is spent to charge the capacitors. For decoupling in scheme diodes are on.
3. After the capacitors are charged, the current rises to the value necessary for the relay to operate. The relay turns off the air conditioner.
4. If the window is already closed, then after the capacitors are discharged (due to the minimum current flow in the opposite direction through the diode), the relay again supplies voltage to the air conditioner.

R. turn-on delay 220v 2 repair option for the refrigerator.

If it is difficult to find a regular temperature sensor, the option is to install any suitable one. And in order for the compressor not to turn on and off, we mount the same circuit as for the air conditioner.

Modernization of the control of 4 power windows

Normally, the windows in the car do not work when the ignition is off. A case is possible - having stopped for a few seconds, we cannot open the window to pay the refueling operator. To eliminate the situation, we modernize the electrical equipment control circuit by setting switch-off delay relay.

Option homemade time relay with a delay of 24 volts

The previous circuit provided power from a 12 volt unit. We offer another option, powered by 24 V. It is suitable for trucks, in their network such voltage.

The device is assembled on domestic elements, canopy installation. With the help of a variable resistor (it is at the very bottom of the circuit), the turn-off delay time is adjusted.

3rd power window control scheme on imported parts

If there are problems with the acquisition of domestic radio elements, we assemble relays with a delay on imported ones. Parts are soldered from the boards of a failed computer. Below is a diagram.

The device works in the same way. By changing the capacitance of the capacitor C1 or resistor R2, we adjust the delay time.

DIY time relay

R. turn off delay 220v fan for 1 hour with your own hands

Another use case delayed relay- fan or extractor control in the shower or lavatory. Here is a diagram for assembling it yourself.

It works in two modes selectable with a switch on the relay. The signal for the relay to operate is the supply of voltage to the lighting of the room.

For shower:

1. Lights are turned on in the room.
2. You are using the bathroom.
3. When you left, you turned off the light.
4. The delay time starts (until steam accumulates).
5. After a delay, the fan turns on for the time necessary to remove the steam.

For restroom:

1. After the light is on, the countdown begins.
2. After half a minute or more (depending on the settings), the hood will turn on.
3. The fan runs for the programmed time.

R. temp. with delayed switch-off options 2 and 3, 220V for exhaust

The proposed scheme can be assembled on imported relays, two options are shown below.

The algorithm of these schemes is as follows.

1. Simultaneously with the inclusion of lighting, the hood is turned on.
2. After the lighting is turned off, the countdown begins.
3. When the delay has passed, the fan is de-energized.

Devices are configured for the operating time after turning off the light is 15 minutes. To change the delay, it is enough to turn the knob on their panel with a Phillips screwdriver or any similar tool.

Scheme for extracting RV with a delay off 220v on a domestic component or option 2 on a device from abb

Instead of with special relays for fan, use multi-functional. The figure below shows domestic models, but it is easy to find and select imported ones.

The option is to choose ABB products.

Devices are connected to the fan power circuit, and then the knobs adjust the operating time and delays.

Domestic relays are two-channel, the second channel can be used to control lighting. To do this, you need to set them so that the light goes out after a time sufficient to use the room. Energy savings are achieved if there are forgetful people in the house.

Homemade R. for delaying the activation of a car alarm

Another option for using the delay is to include it in the car alarm circuit. Variants of this security system block the doors immediately after you close them, this is not very convenient, slamming the car with the keys and the alarm control key fob remains on the street. If you mount the relay with a delay of one or two minutes, the driver will have time to correct the error. Here is a variant of the diagram.

The device is assembled on domestic radioelements by a canopy and is included in the power supply circuit of the security system. By changing the capacitance of the capacitor, you can adjust the delay time.

RV with turn-off delay 220v from 3 best devices from aliexpress

Buying a relay on the aliexpress portal saves money. We list the top three devices on this service.

First, second and third number in our relay rating

Answers to frequently asked questions

At the end of the article, we will answer some of the most frequently asked questions.

Question. Which option is preferable for a 12 V relay and an intermediate one for 220 or immediately designed for high voltage?

Answer. First option more secure when setting up, the second is easier to install.

Question. Which relay is preferable mechanical or electronic?

Answer. Mechanical cheaper, electronic reliability and functionality they are surpassed.

Question. Are imported devices more reliable?

Answer. Russian standards are tougher than foreign ones, so it is preferable to choose domestic devices.

3 common mistakes when choosing R.V.

1. Select a relay whose maximum or minimum adjustable operating period is close to the required operating period. It is necessary that the time that the device will most often work out is in the middle third.
2. The relay is not designed for the connected load. Before choosing, determine the maximum current of the controlled relay devices and study its characteristics.
3. The device intended for premises is mounted in the open air. The relay for outdoor installation must have a protection class of at least IP 68.

We hope this article was not only informative, but also practically useful. It’s great if she helped make the home more comfortable and cozy.

It is possible to activate and deactivate household appliances without the presence and participation of the user. Most of the models produced today are equipped with a timer for automatic start / stop.

What to do if you want to manage outdated equipment in the same way? Stock up on patience, our advice and make a time relay with your own hands - believe me, this homemade product will be used in the household.

We are ready to help you realize an interesting idea and try your hand at the path of an independent electrical engineer. For you, we have found and systematized all the valuable information about the options and methods for manufacturing relays. The use of the information provided guarantees easy assembly and excellent performance of the instrument.

In the article proposed for study, home-made versions of the device tested in practice are analyzed in detail. The information is based on the experience of enthusiastic electrical craftsmen and the requirements of regulations.

Man has always sought to make his life easier by introducing various devices into everyday life. With the advent of technology based on an electric motor, the question arose of equipping it with a timer that would automatically control this equipment.

Turned on for a specified time - and you can go do other things. The unit will turn itself off after the set period. For such automation, a relay with an auto-timer function was required.

A classic example of the device in question is in a relay in an old Soviet-style washing machine. On its body there was a pen with several divisions. I set the desired mode, and the drum spins for 5-10 minutes, until the clock inside reaches zero.

The electromagnetic time switch is small in size, consumes little electricity, has no broken moving parts and is durable

Today they are installed in various equipment:

• microwave ovens, ovens and other household appliances;
• exhaust fans;
• automatic watering systems;
• lighting control automation.

In most cases, the device is made on the basis of a microcontroller, which simultaneously controls all other modes of operation of automated equipment. It's cheaper for the manufacturer. No need to spend money on several separate devices responsible for one thing.

According to the type of element at the output, the time relay is classified into three types:

• relay - the load is connected through a "dry contact";
• triac;
• thyristor.

The first option is the most reliable and resistant to surges in the network. A device with a switching thyristor at the output should be taken only if the connected load is insensitive to the shape of the supply voltage.

To make a time relay yourself, you can also use a microcontroller. However, homemade products are mainly made for simple things and working conditions. An expensive programmable controller in such a situation is a waste of money.

There are much simpler and cheaper circuits based on transistors and capacitors. Moreover, there are several options, there are plenty to choose from for your specific needs.

Schemes of various homemade products

All the proposed do-it-yourself manufacturing options for time relays are built on the principle of starting a set shutter speed. First, a timer is started with a specified time interval and a countdown.

The external device connected to it starts working - the electric motor or the light turns on. And then, upon reaching zero, the relay gives a signal to turn off this load or block the current.

Option # 1: the easiest on transistors

Transistor-based circuits are the easiest to implement. The simplest of them includes only eight elements. To connect them, you don’t even need a board, everything can be soldered without it. A similar relay is often made to connect lighting through it. I pressed the button - and the light is on for a couple of minutes, and then turns itself off.

To power this circuit, 9 or 12 Volt batteries are required, and such a relay can also be powered from 220 V variables using a 12 V DC converter (+)

To assemble this homemade time relay, you will need:

• a pair of resistors (100 Ohm and 2.2 mOhm);
• bipolar transistor KT937A (or analogue);
• load switching relay;
• 820 ohm variable resistor (for adjusting the time interval);
• capacitor at 3300 uF and 25 V;
• rectifier diode KD105B;
• switch to start the countdown.

The time delay in this relay-timer occurs due to the charging of the capacitor to the power level of the transistor key. While C1 is charging to 9-12 V, the key in VT1 remains open. External load is powered (light on).

After some time, which depends on the value set on R1, the transistor VT1 closes. Relay K1 eventually de-energizes and the load is de-energized.

The charge time of the capacitor C1 is determined by the product of its capacitance and the total resistance of the charging circuit (R1 and R2). Moreover, the first of these resistances is fixed, and the second is adjustable to set a specific interval.

The timing parameters for the assembled relay are selected empirically by setting different values ​​on R1. To later make it easier to set the desired time, markings with minute-by-minute positioning should be made on the case.

It is problematic to specify the formula for calculating the issued delays for such a scheme. Much depends on the parameters of a particular transistor and other elements.

Bringing the relay to its original position is performed by reverse switching S1. The capacitor closes on R2 and discharges. After switching on S1 again, the cycle starts anew.

In a circuit with two transistors, the first one is involved in the regulation and control of the time pause. And the second is an electronic key for turning on and off the power of an external load.

The most difficult thing in this modification is to accurately select the resistance R3. It should be such that the relay closes only when a signal is applied from B2. In this case, the reverse switching on of the load must occur only when B1 is triggered. It will have to be selected experimentally.

This type of transistor has a very low gate current. If the resistance winding in the control relay-key is selected large (tens of ohms and MΩ), then the shutdown interval can be increased to several hours. Moreover, most of the time, the relay-timer practically does not consume energy.

The active mode in it begins in the last third of this interval. If the RV is connected through a conventional battery, then it will last a very long time.

Option #2: Chip-based

Transistor circuits have two main disadvantages. For them, it is difficult to calculate the delay time and before the next start it is required to discharge the capacitor. The use of microcircuits eliminates these shortcomings, but complicates the device.

However, if you have even minimal skills and knowledge in electrical engineering, making such a time relay with your own hands is also not difficult.

The opening threshold of the TL431 is more stable due to the presence of a reference voltage source inside. Plus, it requires a much higher voltage to switch it. At the maximum, by increasing the value of R2, it can be raised to 30 V.

The capacitor will take a long time to charge to such values. In addition, connecting C1 to the resistance for discharging in this case occurs automatically. Additionally, you do not need to click on SB1 here.

Another option is to use the "integral timer" NE555. In this case, the delay is also determined by the parameters of the two resistors (R2 and R4) and the capacitor (C1).

“Turning off” the relay occurs due to the switching again of the transistor. Only its closure here is performed by a signal from the output of the microcircuit, when it counts the necessary seconds.

There are much fewer false positives when using microcircuits than when using transistors. The currents in this case are more tightly controlled, the transistor opens and closes exactly when required.

Another classic microcircuit version of the time relay is based on the KR512PS10. In this case, when the power is turned on, the R1C1 circuit supplies a reset pulse to the input of the microcircuit, after which the internal generator starts in it. The shutdown frequency (division ratio) of the latter is set by the control circuit R2C2.

The number of pulses to be counted is determined by switching the five outputs M01-M05 in various combinations. The delay time can be set from 3 seconds to 30 hours.

After counting the specified number of pulses, the output of the Q1 chip is set to a high level, which opens VT1. As a result, relay K1 is activated and turns the load on or off.

The assembly scheme of the time relay using the KR512PS10 microcircuit is not complicated, resetting to the initial state in such a PB occurs automatically when the specified parameters are reached by connecting the legs 10 (END) and 3 (ST) (+)

There are even more complex time relay circuits based on microcontrollers. However, they are not suitable for self-assembly. There are difficulties with both soldering and programming. Variations with transistors and the simplest microcircuits for domestic use are enough in the vast majority of cases.

Option #3: powered by 220V output

All of the above circuits are designed for a 12-volt output voltage. To connect a powerful load to a time relay assembled on their basis, it is necessary at the output. To control electric motors or other complex electrical equipment with increased power, you will have to do this.

However, to adjust household lighting, you can assemble a relay based on a diode bridge and a thyristor. At the same time, it is not recommended to connect anything else through such a timer. The thyristor passes through itself only the positive part of the sine wave of 220 Volt variables.

For an incandescent bulb, fan or heating element, this is not scary, and other electrical equipment of this kind may not withstand and burn out.

The time relay circuit with a thyristor at the output and a diode bridge at the input is designed to operate in 220 V networks, but has a number of restrictions on the type of connected load (+)

To assemble such a timer for a light bulb, you need:

• constant resistance at 4.3 MΩ (R1) and 200 Ω (R2) plus adjustable at 1.5 kΩ (R3);
• four diodes with a maximum current above 1 A and a reverse voltage of 400 V;
• 0.47 uF capacitor;
• thyristor VT151 or similar;
• switch.

This relay-timer operates according to the general scheme for such devices, with the gradual charging of the capacitor. When the contacts are closed on S1, C1 starts charging.

During this process thyristor VS1 remains open. As a result, a mains voltage of 220 V is supplied to the load L1. After charging C1, the thyristor closes and cuts off the current, turning off the lamp.

The delay is adjusted by setting the value on R3 and selecting the capacitance of the capacitor. At the same time, it must be remembered that any touch to the bare legs of all used elements threatens with electric shock. They are all powered by 220V.

If you don’t want to experiment and assemble the time relay yourself, you can pick up ready-made options for switches and sockets with a timer.

More information about such devices is written in the articles:

Conclusions and useful video on the topic

Understanding the internals of a time relay from scratch is often difficult. Some lack knowledge, while others lack experience. To make it easier for you to choose the right circuit, we have made a selection of videos that describe in detail all the nuances of the operation and assembly of the electronic device in question.

If you need a simple device, then it is better to take a transistor circuit. But to accurately control the delay time, you will have to solder one of the options on a particular microcircuit.

If you have experience in assembling such a device, please share the information with our readers. Leave comments, attach photos of your homemade products and participate in discussions. The contact block is located below.