This is the 5th part of the popular heading - "question-answer on electricity". Who missed the previous parts - as always, I remind you that in this and past publications (parts) I bring real questions from readers and my answers to them. Well, I will continue to do this in this 5th part!
Question N1 from Nikolay:
Greetings, please tell me how to connect a 380 V to 220 V electric motor? The problem is there are 3 wires coming out of the motor.
My answer to it was as follows:
The possibility of connecting an electric motor from 380 V to 220 V must be provided for in the passport data. To do this, there must be a corresponding mark on the nameplate of the electric machine - the winding connection is delta / star, voltage - 220/380 V:
Some manufacturers may exclude this possibility, then only one voltage rating will be indicated on the nameplate of the electric motor. Note that some electrical machines may be designed for other voltage ratings.
If such a mark is available on your engine, then you need to open the bore, in which the windings are connected:
Change the type of connection of the windings to the one you need for power supply from the corresponding voltage rating. You can find more detailed information on this issue in the corresponding article on our website: https://www.asutpp.ru/kak-podklyuchit-elektrodvigatel-s-380-na-220.html
Question N2 was asked by Alexey. I quote it verbatim:
I decided to lengthen the webcam with 18 meters of cable. Two different cables, 4-wire and 8-wire, since it was not so long. I connected the 1st to the webcam. Green to green, red to orange, black to white-orange, white to white-green. Works. But the second half remained. I tried to connect by colors, it does not work. What is the reason?
I gave the following answer:
If I understood you correctly, then you connected a 4-wire cable to the webcam and it turned out that it works. But by adding an 8-core cable to the circuit, it turned out that the camera no longer works? In this case, the most likely option is too high resistance of the entire signal transmission circuit.
The thing is that the signal from the camera is relatively weak, since it is transmitted with a voltage of only 5 V. The conductor itself represents a certain amount of resistance, and the places where the wires are connected may have too much ohmic resistance. Therefore, in accordance with Ohm's law, the higher the resistance of a section of the circuit, the greater the voltage drop across it, and the less current will flow in it. Because of this, the signal at the receiver will be so weak that the computer simply will not perceive it as incoming data. Soldering or a larger cable can be a solution to the problem.
Another variant of the problem may be a mismatch in the color coding of the wires. Although this situation is rare, it is advisable to ring the cable cores before connecting to prevent possible errors.
Perhaps, as an option, some pair of wires were poorly connected. Such a disadvantage is often observed with different lengths of the conductors, which are connected by twisting. Longer wires stretch the entire cable, while shorter ones stretch and come out of the twist.
Question N3 was asked by Roman:
Hello! At night I put the phone to charge, but after 2 hours I woke up from the fact that it turned on and off, we found out that voltage appears and disappears in the outlet. However, no work was carried out. With other outlets, everything is fine. What could it be?
I gave the following answer:
I would like to know how you checked that voltage appears and disappears in the outlet. If you did this with a multimeter or control, then the reason is clearly in the connection point itself. Most likely, the contact at the place where the cable core was connected to the socket clamp was loosened, perhaps the core in this place began to burn. To fix the problem, you will need:
- Remove the false panel, as a rule, it is fastened with a bolt in the center;
- Release the locking tabs and pull the socket block out of the landing box;
- Visually inspect the places where the cable is connected to the outlet, you may find visible damage or blackening;
- The place of damage is cleaned and tightened with a bolt clamp until the core is securely fixed;
- The repaired socket is installed in the reverse order.
Please note that all work on the revision of the electrical outlet must be carried out with the voltage disconnected. Be sure to check the absence of voltage with an indicator screwdriver or a tester.
If the lack of voltage was checked only through the phone, then in addition to the above-described reason, there may also be a malfunction of the charger or connector in the mobile. To check the connection point, it is enough to check it with a multimeter or connect another, obviously working device to this outlet. If it works fine, then the reason is not in the outlet.
P.S. Past parts of the answers to the questions:
Part 1, Part 2, Part 3, Part 4