Two fingers of the same hand are in contact with the two binding posts of the transformer s 220 volt

The "safe extra low voltage" that allows continuous contact under normal ambient conditions is 50 V.

The human body's response to electric currents:

8 10mA hands have difficulty getting rid of the electrodes and have a sharp pain (finger joints).

20 25mA hands quickly paralyzed, unable to get rid of electrodes automatically, breathing difficult.

50 80mA is difficult to breathe, and the atria begin to tremble.

90 100mA respiratory paralysis, after three seconds the heart begins to paralyze and stops beating.

The degree of harm of electric current to the human body is related to various factors such as the intensity of the current passing through the human body, the duration of the electric current, the frequency of the current, the way the current passes through the human body, and the physical condition of the electrocutor.

1. Current intensity: The greater the current intensity, the greater the harm to the human body.

The greater the current through the human body, the more obvious the physiological and pathological response to heat, the shorter the time it takes to cause ventricular fibrillation, and the greater the fatal risk. Under normal circumstances, 30mA is the maximum current that the human body can tolerate without fatal danger, that is, the safe current.

The longer the duration of the current passing through the human body, the decrease in the resistance of the human body due to sweating, breakdown, and electrolysis, and the more external electrical energy accumulates in the body, the stronger the central nervous system reflex, and it may coincide with the vulnerable period of the heart, and the greater the danger to the human body.

3. The way in which the electric current passes through the human body.

There is no absolutely safe way for the human body to be under the action of electric current. Passing an electric current through the heart can cause ventricular fibrillation and death when the heart stops beating. When an electric current passes through the central nervous system and related parts, it will cause a strong imbalance of the central nervous system and lead to death; Electrical currents pass through the head, causing severe damage to the brain and possibly stuporing and death. The passage of electrical current through the spinal cord can paraplegic; The passage of electrical current through a person's limbs may also cause strong reflexes in the central nervous system, which can lead to serious consequences.

The more current that flows through the heart and the shorter the current route, the more dangerous the path.

Fourth, the condition of the human body itself.

The gender, age, health, mental state, and body resistance of the person being electrocuted will all have an impact on the consequences of electric shock. People with heart disease, central nervous system disease, and lung disease are at greater risk after electric shock; People with poor mental state and intoxication are at greater risk of electrocution; The consequences of electrocution in women, children, and the elderly are more serious than those in young adults.

People will be electrocuted, at this time the human body and the fingers can be regarded as in parallel, there will also be an electric current flowing through the person's body to the ground, 220V is enough to kill!

An electric current flows between the two fingers and burns both fingers.

Think of your finger as a wire, and then measure the resistance between your two fingers to 1000 ohms.

220 1000=, that is, 220 milliamps, enough for you to suck and dance.

The binding posts appear in pairs, and one of them is connected to the corresponding input voltage, and the rest is the corresponding output voltage. For example, if the input voltage is connected to 220V, the output voltage will be 127V, 28V, and 6V.

If there is a 127V power supply and a 127V pile, there is an output voltage of 220V 28V 6V.

When the transformer leaves the factory, the input and output are separated, with one side being the output and the other being the input.

The wire diameter used for the two 220V is also different, and the thick one is the input terminal.

Also, there are obvious signs on the transformer, take a closer look.

The two 220-volt binding posts are the primary input posts, and the others are the outputs.

This can require two binding posts to be customized as a group, that is to say, no zero line.

If you have a hands-on basis, you can reduce the number of winding turns of the output winding by half. If DC is required, a diode connected to the output will also suffice.

There is no need to change the transformer, just add resistor, capacitance and step-down at the input terminal.

There is a decrease or increase in the number of turns.

It was originally yes, but do you still need to change it?

Ever seen the S7 series transformer (obsolete product??) Both the high-voltage side and the low-voltage side are with 12 screws, which I have removed. The rest is not clear.

This question is unanswerable.

The first step is to figure out the two wires at the input end;

In the second step, the output of four wires is to distinguish the same group of two wires with a multimeter;

The third step, two wires of different groups are randomly connected to one of them, and the voltage of the remaining two is measured with a multimeter, if the voltage is zero, these two wires are the same name end, and if the voltage is 24V, these two wires are the different name end.

Next, it depends on what type of output you want, if the requirement is plus or minus 12V power supply, connect the different name end as a common ground (GND), and the other two are connected to the diode bridge, the positive output is positive 12V, and the negative output is negative 12V;

If the requirement is 24V output, the connection method is the same, take negative 12V as the ground, and positive 12V is 24V output;

If the requirement is 12V output, then congratulations, you connect each of the two groups to the diode bridge, and you have two sets of 12V power supplies, of course, you can only use one of them.

It should be a 220V 12V+12V transformer. There are two possibilities:

1) 220V as a group, the shielded wire is a single one, and the 24V center tap, that is, 12+12. Use a multimeter to measure DC resistance, shield wire and other arbitrary wires are not through, the larger resistance group is 220V, the resistance between the other 3 binding posts is very small, with a low resistance measurement, you can distinguish the resistance is slightly larger is 0V and 24V, the other is 12V.

2) 220V, 12V, 12V three groups independent. The group with the larger resistance is 220V, and the two with small resistance and the difference between the two are 12V. Two 12V phases can be energized in series, and it can be easily done to see whether the voltages are superimposed or cancelled out.

If the above two conditions are not met, then the transformer is structurally different or problematic.

Generally, the first thick end is the inlet end (the primary side of the transformer), and the thin wire is the secondary side, and each winding can be measured with a multimeter.

If you really don't understand, connect to the power supply, measure the voltage of each terminal on the secondary side and then determine it.

Small transformers can be used, but they should be handled safely.

This is called a self-coupling transformer, and the promised voltage can achieve the purpose, but it also carries high voltage, so it is necessary to pay attention to safety.

How big is the transformer, and the voltage level?

Is 10kv a triangle connection transformer comes out with 4 transformers is a star connection.

This is a three-phase power transformer, so the input power line is three-phase, and of course there are three binding posts.

Three live wires, voltage 380V, only one live wire and one neutral wire (neutral line) are needed to connect to a household.

Look at the signs: ABC is high pressure, ABC is low pressure, high pressure side from left to right is ABC, low pressure is from right to left, ABC

The high-voltage terminal post is thin and the low-voltage terminal post is thick, and the neutral line of the general power transformer is generally on the low-voltage side.

Look at the letters and look at the size of the terminals, and whether there are three and four posts in the two rows of terminals, and the size of the insulator. Then the letter is large or the terminal row is three binding posts or the paper body is large for the high voltage side, then the other side is the low voltage side.

You use a universal meter to measure the resistance on both sides.

If it's a step-down transformer.

The large resistance should be connected to the high-voltage end, and the small resistance should be connected to the low voltage.

Very simple, the low-voltage outgoing line with the small porcelain gourd and the high-voltage incoming line with the large porcelain gourd.