I continue to publish publications in the Q&A format for electrical. Real questions and professional answers. " As always, you can familiarize yourself with the previous parts of the answers to questions by clicking on the links that are at the bottom of this publication. In this publication you will find 2 interesting, in my opinion, questions and answers to them.
Question N1 was asked by Slava:
The problem is this, the unicycle, when you give gas on charging, works, and the indicator on the charging unit shows that charging is in progress when the unicycle is just standing on charging, after turning off the charging, it simply does not turn on, the voltmeter and ammeter show that nothing is working - there is no voltage type, help, tell me what problem? Is there a malfunction in the mono-wheel or in the charging unit?
I gave the following answer:
In the situation you described, the most likely malfunction of the unicycle battery itself. If you claim that the monowheel is working normally when connected to the charger, then there is enough power from the electrical circuit to start the engine.
To check which particular node has become unusable, you need to use a multimeter. If you plug the charger into a power outlet and install the multimeter leads on the plug, connected to a monowheel, then with good charging you will see the voltage value set by the factory manufacturer. Also, if possible, it is worth checking the value of the charging current, for this the ammeter is included in the open circuit of the power supply, and the value is compared with the factory one. As a rule, the value of voltage and current is indicated on the charger itself or in its passport. A fully functional charging will correspond to the factory parameters, in case of a significant difference, the charger is faulty.
If the voltage at the output of the charger is correct, the battery itself should be checked. To do this, you should measure the battery capacity with the same multimeter. The factory value is also indicated in the passport of the electric unicycle or on the battery itself, if the measured capacity is significantly less, then the battery is faulty. It is also possible for an open circuit in the battery, but this is an extremely rare case.
Question N2 was asked by Dmitry. The question itself is literally:
Good day. I took out an old heater from the garage, but the cord in the plug was somehow very unnaturally walking there. I decided to unscrew the "tighten the bolts", I saw the following picture: the yellow wire is in the air and is not connected anywhere, should it be like this or should it still be pressed under the left bolt? The last time a couple of years ago the heater worked, now I don’t dare to plug it into the socket)) Do not blame me for profanity, I do not drag in an electrician, so I decided to ask the specialists) thank you.
Dmitry attached the following photos to his question:
I gave the following answer to this question:
Hello!
Hello, in your photo you have a fully capable circuit of a domestic heater, as in principle, and any other household appliance. In the diagram, you have three wires: brown and blue - this is the phase conductor and the neutral conductor, which are connected to the plugs, and yellow-green, as regulated by GOST 33542-2015, is a protective conductor (PE). Otherwise, it all depends on what kind of power supply scheme is used in your apartment.
If all household appliances are powered via a two-wire system - only the phase and neutral conductors, then the protective ground is in no way involved. It is a normal situation that in the PE device itself the conductor is pulled away from the corresponding terminal (clamp).
Such a technical solution, most likely, was due to an attempt to protect oneself and households from accidental electric shock or disconnection of protective grounding as unnecessary. In the first case, some power supply circuits in emergency mode can lead to a dangerous potential on the equipment case through the protective conductor, so it is turned off in advance. If you only have a phase conductor and a neutral conductor throughout your home, then I recommend that you not only do not screw on, but also additionally insulate or bite off this core so that it does not short-circuit two others.
If you have a grounding device at home or the power supply is carried out via a three-wire system, not using protective earth ground can be dangerous from the point of view of electric current. In this case, be sure to connect the yellow-green wire to the corresponding terminal (clip) inside the plug.
P.S. Link to past parts - Part 7,Part 6, Part 5 and Part 4.