Ask the master The power of the thermostat is small, can it be solved by adding an AC contactor? How

It can be solved. What kind of thermostat are you, there is a circuit diagram on the manual of the thermostat, you want to see that the two points are electric shock output, there are two electric shock outputs, that is, two normally open, two normally closed. When the temperature reaches the set value, the normally open electric shock is turned on, and the normally closed electric shock is disconnected.

You can connect these two points with the coil of the AC contactor and you can control it. As for whether the relay is automatically reset or manually reset, it depends on the connection method of the relay later. You can make the feature requirements clearer and take the time to draw a diagram for you.

If you want to let the temperature control table control, you must install the corresponding module, according to the model of the table, some of the table comes with, the output point of the table is a passive contact, it is recommended to use it to control the small relay, there is a small relay to control the contactor is safer, that is to say, the table output ground contact is connected to the coil power supply of the small relay, (the recommended relay is 24V) to ensure the effect of isolation, how to connect: the normally open contact of the table output controls the line of a coil of the small relay 24V, and the other end of the small relay coil is directly connected to 0V. Then the normally open point of the small relay is connected to the coil of the contactor, which is done, if you don't want to use the small relay, just change the small relay to the contactor in my previous steps, I hope it can help you.

Absolutely, the temperature controller is only on the control loop, and the control of large current by small current is generally done through AC contactor.

It is OK to connect the two binding posts of the thermostat and the coil of the contactor in series, that is to say, the 220V live wire is connected to one binding post of the thermostat, the other binding post is connected to the A1 of the coil of the contactor, and the A2 of the contactor is connected to the zero wire, so that it is OK.

Thermostat control method:

The control method is generally divided into two kinds: one is controlled by the temperature change of the cooled object, and the vapor pressure temperature controller is mostly used, and the other is controlled by the temperature difference change of the cooled object, and the electronic temperature controller is mostly used.

It adopts fuzzy control techniques such as PID control, P(proportional) proportional + i(integral) integration + D (differential) differential control.

To tell you a little more colloquially, the coil of the contactor is used as a light bulb, and the thermostat can be used as a switch, understand?

First look at the AC contactor is 220 volts or 380 volts (see the coil of the contactor is marked below or near the binding post) The wiring is 220 volt terminal posts 1, 3, 5 (L1, L2, L3) connected to 380 volts of three phase wires, the phase wire enters 2, 4, 6 (T1, T2, T3) is connected to the three terminals of the electrical appliance (three resistance wires of 380 volts are marked nearby), the two connectors of the thermostat are connected to one of the three at one end of L1, L2, L3, and the other connector is connected to AC contactor A1, A2 One of the two contactors, the remaining one joint A1, (or A2) is connected to the zero line (the zero line of the three-phase four-wire) AC contactor is a 380 volt connection terminal post 1, 3, 5 (L1, L2, L3) connected to three phase wires of 380 volts, the phase wire enters 2, 4, 6 (T1, T2, T3) is connected to the electrical appliance three terminals (380 volt three resistance wire three connectors) thermostat two connectors, one is connected to L1, L2, L3 any of the three, and the other connector is connected to AC contactor A1, A2 One of the two contactors, the remaining one connector A1, (or A2) is connected to L1, L2, L3, one of the remaining two of the three, because I can't make drawings on the computer, so I can only tell you like this, I hope it will help you.

Take the 220V contactor of the coil to dictate: take the 220V power supply to connect the temperature control, and the phase wire of the DU temperature control.

Short the first line to the total or com, the temperature controlled low or no to connect the contactor A1, A2 to the N line; 380V coil, temperature control power supply to L1 N, the same L1 to the total or com, outgoing wire to A1, A2 to L3, it is best to add insurance on L1 line.

AC contactors.

It plays the role of turning on or off the power switch in the circuit, and its working principle is similar to that of AC relays, but the number structure of the special electromagnetic switch and the use of the occasion and installation method are different. AC contactors are commonly used for load rated currents.

Electrical circuits greater than 10A and starting current of 60A or more.

The AC contactor used in the air conditioning electrical system is generally 220V for the rated base voltage of the control coil, and the current loop of the first circle is connected by connecting it with the relay contact, and the connection or disconnection of the contact is carried out through the connection or disconnection of the contact, so as to control the on/off of the circuit power supply and achieve the purpose of controlling the load of high-power electrical appliances.

Take the XT-640W intelligent temperature controller produced by Shanghai Gongbao Electric as an example.

First, the AC contactor is connected in series to the normally open contacts of the relay inside the instrument. When the measurement temperature of the instrument is lower than the set value, the normally open contact of the relay is engaged, and the AC contactor is also energized and engaged, and the load heats up due to the energy obtained. Conversely, the load cools down due to the loss of energy.

The wiring method is shown in the figure.

The temperature controller generally outputs 24V, so if you want to use a low-voltage coil, you can connect it directly.

First, look at the instructions of the temperature controller.

If the contacts of the output relay of the controller are independently isolated (not directly connected to the power supply and circuit of the controller), the coil of the contactor can be connected in series to the power supply of the corresponding voltage level according to the coil voltage of the contactor.

For example, the coil of the contactor is AC220V. The live wire of the AC220V power supply is connected to one output point of the controller Out1, the other output point Out2 is connected to one point of the contactor coil (A1), and the other point of the coil (A2) is connected to the neutral line of 220V?

The contactors are divided into single-phase and three-phase, and the coil voltage is also available in voltage levels such as 220V and 380V. It should be connected according to different voltage levels.

1. If it is a contactor for equipment control of 220 coils:

As long as the lead wire is on the L-line pile of the working power supply of the thermostat, the wire is connected to a pile on the normally open pile for the control of the thermostat. Control the coil end of the contactor with another pile connection device. The other end of the device contactor coil is connected to the n-wire.

2. If it is a contactor for equipment control of 380V coil:

It is to lead a wire on the L-line pile of the working power supply of the thermostat (assuming the A-phase power supply of the three-phase power supply) to one of the heads of the control normally open pile of the thermostat. The thermostat is controlled by the other end of the normally open pile attached to one end of the contactor coil of the equipment. The other end of the equipment contactor coil is connected to phase B of the three-phase power supply.

There will also be detailed instructions in the manual of the general thermostat. If you still don't understand, please provide the specific model of the thermostat and contactor.

Take the 220V contactor of the coil to dictate: take the 220V power supply to the temperature control, short the phase wire of the DU temperature control to the main or com, and connect the low or no of the temperature control to the A1 and A2 lines of the contactor; 380V coil, temperature control power supply to L1 N, the same L1 to the total or com, outgoing wire to A1, A2 to L3, it is best to add insurance on L1 line.

AC contactor plays the role of turning on or off the power switch in the circuit, and its working principle is similar to that of AC relay, but the number structure of the special electromagnetic switch, the use of the occasion and the installation method are different. AC contactors are often used in electrical circuits where the load rated current is greater than 10A and the starting current is more than 60A.

I also found that a lot of people like to copy things from some places, drawing is not how to do it, what you said is the simplest circuit, buy a contactor-controlled thermostat, with a thermostat is more than 4,6 feet any foot to control the contactor coil is good is the normally open two, and in the power input of the live wire and a line to 4 or 6 feet, this is the most important, people who have not used it are mostly this does not understand (the wiring diagram in the thermostat is not indicated) that thermocouple red connection to the positive electrode, tried it, I don't know how to ask again, You'll think that you know something about it

The selection method of AC contactor The selection of contactor should be carried out according to the requirements of the controlled equipment, in addition to the rated working voltage should be the same as the rated voltage of the controlled equipment, the load power, use category, operating frequency, and working life of the controlled equipment. Series-parallel use of contactors Many electrical devices are single-phase loads, so several poles of a multipole contactor can be used in parallel.

Electronic thermostat. Timing Counting Series. Intelligent Time Relay · Digital Time Relay · Intelligent Counting Length Meter Frequency Meter · Length Sensor. Portable meter Sensor name.

The thermostat should give it a signal for the highest and lowest temperatures! Add an extra relay! The following AC contactors are represented by KM, relays are represented by KA, and temperature control is represented by WD.

The coil voltages are all set to 380! Connect the 380V yellow wire to the common end of the WD, and connect the WD normally closed point to the KA coil. The WD normally open point is connected to the common end of the KA, and the NO point of the KA is connected to the coil of the KM.

Connect the green wire of the 380 to the coils of the KA and KM. This is the secondary line. Connect the 3 phases to the km normally open point in one line, and connect the heating element on one side.