Can the heating resistance be replaced by a small resistance?

No. First of all, the size of the resistance is compared, and it is very general to say that the small resistance is very general.

However, the heating resistance should not be too small. For example, if the heating resistance of the soldering iron is close to the wire, the current is very large in order to maintain a high power during heating, so that the wire is like a heating resistance, and a lot of voltage is distributed to the wire, and the wire is seriously heated, and there is a fire hazard. Excessive current can also cause the fuse to blow.

It is enough to use a larger resistance, because of its large resistance, under the same power, the current is smaller, the voltage division on the wire is smaller, and the loss on the wire is also very small.

Do you mean by "heating resistance" the resistance used to heat the heat? If that's the case, it depends on what you're heating for, what you're heating for, and how much energy it needs to consume, i.e., how much power it has. It is also necessary to know what the voltage supplied by the power supply is, whether it is 220 volts or how much, then the value of the resistance should be the square of the voltage divided by the power.

r=u^2/p。Or, p=U2 r, if the resistance is small, the power will increase, and if the resistance is large, the power will be smaller. Don't you see?

The heating resistor is designed to generate heat, and it is normal to generate heat. Ordinary resistance is heated only when the power is large, and the resistance value is easy to change and easy to burn out. Therefore, it cannot be replaced.

According to the U-square ratio R, the heating resistance should be a small resistance.

Summary. Kiss, not replace! Because the performance of the two is different. Here's why

First, the melting point is different.

1. Resistance wire: The melting point temperature resistance of resistance wire can reach 1450 degrees.

2. Electric heating wire: The melting point of the heating wire should be lower than that of the resistance wire.

Second, the chemical composition is different.

1. Resistance wire: The material of resistance wire is iron-chromium-aluminum, iron-chromium-nickel.

2. Electric heating wire: The material of the heating wire is iron-chromium-aluminum electric heating alloy.

Can resistors replace heating wires.

Kiss, you can't replace the stool! Because the performance of the two is different. Here's why

1. Different melting points 1. Pure resistance wire: The melting point temperature resistance of resistance wire can reach 1450 degrees. 2. Electric jujube silk:

The melting point of the heating wire is lower than that of the resistance wire. 2. Different chemical compositions 1. Resistance wire: The material of the resistance wire is iron-chromium-aluminum, iron-chromium-nickel.

2. Electric heating wire: The material of the heating wire is iron-chromium-aluminum electric heating alloy.

Dear, in general, Cong Jing takes the melting point difference between the two is too much, and the protective effect on the circuit is weak, if there is no problem with short-term use, the long-term teacher does not recommend you to replace it!

Nowadays, there are many ways of electric heating, such as water heaters, which generally use resistance to heat, but there are also induction cookers, microwave ovens, etc., which are also electric heaters. Resistance heating is just one way of electric heating.

Electric heating includes resistance heating.

1. Electric heating is the conversion of electrical energy into heat energy. This includes electrical resistance heating (heating fast, etc.), electromagnetic induction (induction cooker), short-wave heating (microwave oven, etc.), etc.

2. Resistance heating is directly heated by resistance heating. For example, electric stoves, fast heating, rice cookers, etc.

All in all, resistance heating is the energy utilization rate is relatively low, and electromagnetic induction heating is the highest utilization rate.

Resistance heating refers to the Joule effect, which uses an electric current to flow through a conductor.

The heat generated by the energy is carried out on the material. There are two types of resistance heating: indirect resistance heating and direct resistance heating. Heating resistors.

It is the use of resistance to generate electricity.

Appliances that heat specified objects. It works on the same principle, both use resistors to generate heat. But heating resistors are better than soldering irons.

It's more complicated, let's say it has temperature control circuitry. sensors, etc. For example, there are engine air intakes on cars.

When the cold car starts, the air flowing into the engine is heated to help the cold car start, and when the engine temperature reaches a certain value after starting, the temperature control circuit controls the heating to stop heating. Resistance heating - A heating method that uses an electric current to heat a blank by discharging heat through an electric heater. The common resistance wire heating, ceramic heater, resistance ring heating, quartz tube heating, in principle, belong to resistance heating.

The Joule effect of electric current is used to convert electrical energy into heat energy to heat objects.

It is usually divided into direct resistance heating and indirect resistance heating. The power supply voltage of the former is directly added to the heated object, and when there is a current flowing through, the heated object itself will be heated by the electric heating machine. The object that can be heated by direct resistance must be a conductor, but with a high pure resistivity.

Since the heat is generated by the heated object itself, it belongs to internal heating, and the thermal efficiency is very high. Indirect resistance heating is required by specialized alloy materials.

or a heating element made of non-metallic materials, from which heat energy is generated and transmitted to the heated object through radiation, convection and conduction. Since the heated object and the heating element are divided into two parts, the type of heated object is generally not limited, and the operation is simple. <>

A heating resistor is an electrical appliance that heats a specified object by using a resistor to generate electricity. It works on the same principle, both of which use resistors to generate heat through electricity. But a heating resistor is more complex than an electric soldering iron, for example, it has a temperature control circuit.

sensors, etc. For example, there are engine air intakes on cars. When the engine temperature reaches a certain value after starting, the temperature control circuit controls the heating to stop the heating cracking.

It is normal for the resistance to heat up when braking, as long as it does not exceed the normal range; When the inverter starts braking frequently, the braking resistor heats up seriously, and it is normal for the frequency to decrease when the frequency drops; When the braking resistor is seriously heated, pay attention to check its power, as long as it does not exceed the rated range, it is OK; If the inverter has not yet braked and the braking resistor has been seriously heated, it means that there must be a fault; When the resistor is seriously heated and the resistor power exceeds the rated power, it is necessary to replace the resistor with a larger rated power. <>

Resistivity is used.

The main reason for the large alloy wire is to reduce the size of the heater (body key only small volume).

The truth is: in the electric power.

and voltage is determined in the case that the resistance of the heater is determined. The law of resistance by metal conductors.

Know: in the case of a certain resistance, the length of the heating wire is inversely proportional to its resistivity (a certain diameter, that is, a certain cross-sectional area of the conductor), that is, the resistivity of the large alloy wire can be used shorter, and the heater can be made smaller (the volume is small), "heat fast."

It is a small electric heater (do not understand it as a small power).

You're ignoring one condition: the heater's power rating.

The rated power of the heater has been determined when it is designed, the rated power has been determined when the resistance is determined, the resistance with a large rated power is small, and the current is large: the resistance with a small rated power is large, and the current is small: in other words:

If the rated power of the heater is large, the heating will be fast, and vice versa.

Special note: at the rated voltage.

In the case of a determined power rating, the resistance of the heater is determined, and the resistance must be the same whether you use an alloy wire with high resistivity or an alloy wire with low resistivity. Don't think that if you use an alloy wire with a high resistivity, the resistance will be large!

Repeat: in the case of a certain resistance, the length of the heating wire is inversely proportional to its resistivity (the cross-sectional area of the conductor is certain), that is, the alloy wire with high resistivity can be used shorter (the key is: short-mountain He).

It cannot be heated with a thermistor.

1. The power of the thermistor is too small to achieve the purpose of heating.

2. After the thermistor is heated, it cannot truthfully reflect the temperature of the measured object (or environment).

A simple thermostat can use the following components:

1. 3 fixed resistors.

2. 1 potentiometer.

3. 2 comparators.

4. 2 transistors.

5. 1 relay.

6. 1 diode.

The thermistor is connected in series with a fixed resistor, the voltage at the series point is connected to the positive end of the comparator, the negative end of the comparator is connected to the middle tap of the potentiometer, the two ends of the potentiometer are connected to the power supply and the ground respectively, the output of the comparator is connected to the common emission amplifier composed of the transistor, the triode output drives the relay, and the two ends of the relay winding are connected to a diode in reverse parallel, which is used as the back EMF freewheeling circuit of the coil when the relay is broken.

The temperature control temperature can be changed by adjusting the potentiometer.

The thermistor can only measure the temperature and change the resistance value.

Resistance wires can be used for temperature control, and rheostats are required.

Thermistors are generally used as sensing elements and are not used for heating.

Heating can be done with equipment such as resistance wires, which is convenient to control.

With thermistor detection, the supporting control instrument (or circuit) is controlled, the heating wire is energized and heated when the temperature is not reached, and the heating is stopped after the temperature is reached. This makes it possible to achieve temperature control.

1.Thermistors can be heated. A thermistor is a temperature sensor that senses temperature changes. The thermistor converts the monitored temperature transformation into a resistance transformation, which in turn converts the voltage conversion through the measurement circuit.

2.It should be combined with a relay to achieve temperature control heating and stop heating.

Let's reverse this problem, first of all, the first point, heating must be greater than the insulation power, this is for sure, the power depends on what, the power is equal to the voltage multiplied by the current, and the current is equal to the voltage divided by the resistance, that is, the greater the resistance, the smaller the current, the smaller the resistance, the current will be large, and the power will be large, so that it is not difficult to distinguish, when the power is small, it means that the current is small, and the current is small, which means that the resistance is large, ·· The reverse continues.

Let's reverse this problem, first of all, the first point, when heating, it must be greater than the insulation power, this is for sure, the power depends on what, the power is equal to the voltage multiplied by the current, and the current is equal to the voltage divided by the resistance, that is, the larger the resistance, the smaller the current, the smaller the resistance, the current will be large, and the power will be large, so that it is not difficult to distinguish, the power is small when insulation, which means that the current is small, and the current is small, which means that the resistance is large, ·· The reverse continues.