1. ... Multi-position switching devices on schematic electrical diagrams of automation projects should be depicted in accordance with the instructions given in table. 4 GOST 2.55-87.
vertical dashed lines - switch handle positions (five positions);
the numbers 1, 2, 3, 4, 5 above the dashed lines are a conventional numeric designation of the switch handle positions corresponding to the explanatory inscriptions applied to the product, for example, "DIST", "MEST", "AVT". The conventional numerical designation of the handle positions must have a corresponding explanation in the free field of the diagram. Instead of conventional numeric designations of the handle positions above the dashed lines, you can put down the explanatory inscriptions "RIST", "MEST", "AVT", or the position of the handle in degrees 0 °, + 45 °, + 90 °, etc., if they fit parallel to the title block;
the numbers above the circles on solid horizontal lines (for example) are the designation of the pins of the switch contacts);
thickened line on the dashed line (switch handle position), where x is the switch function - the closing position of the corresponding contacts;
designation of the locking mechanism in accordance with GOST 2. 21-74;
dashes above the designation of the locking mechanism on the vertical dashed lines of the switch positions - the switch locking position.
The example shows a conventional graphic designation of a switch that has three fixed positions (2, 3, 4) and two non-fixed positions (1, 5) with self-resetting from position 1 to 2 and from position 5 to 4.
1. ... The designations of the latching mechanism and the latching positions of the switches are shown only when the switches have fixed and non-fixed positions.
When drawing images of switches having only fixed positions, the designation of the latching mechanism and latching positions should not be shown. For example, if the switch shown in item 1. had not three fixed positions, but all five, then it would have to be depicted as follows:
1. ... Multiposition switches, in which the closing position of the corresponding contact at the same switch positions changes depending on the movement of the switch handle from left to right and from right to left, are depicted as follows (using the example of the conventional graphic designation of the PMO switch with contact 93):
Vertical and horizontal lines, numbers, circles and (x) in the given conventional graphic designation of the switch have the same purpose as in the example of item 1..
The instrument panel on the VAZ 2114 is a whole complex of interacting sensors and equipment. Therefore, it is difficult to determine exactly why it does not burn. However, the problem in most cases arises from one or more of the following faults:
For those who are familiar with the basics of automotive electrical VAZ 2114, it will not be difficult to independently find the cause of the breakdown. To do this, you will need to carry out a number of dismantling works and check the availability of power supply in individual nodes, armed with a tester or voltmeter.
There are many reasons for this malfunction. The wiring of the VAZ-2114, like all domestic cars, is not the strongest part. The most common reasons for backlight failure are:
A voltmeter and a tester will help you find the cause of the malfunction. With its help, it will be possible to check the wiring sections and lamps. Also, the device will help you find out which fuse has failed. In most cases, you will have to remove the dashboard. We will talk about this procedure further.
Turning off the dashboard backlight does not bode well for either the driver or the vehicle. Because this malfunction is usually followed by others. Therefore, the backlight should be repaired immediately.
It should also be understood that if the lights on the dashboard have gone out, then the problem must be looked for somewhere in the on-board electrical network. This means that you cannot do without a multimeter, a soldering iron and electrical tape. Here are the main reasons for turning off the backlight:
are the resistances in the places where the current passes from one contact surface to another through the areas of their actual contact. Such a contact connection per unit of time releases a certain amount of heat, proportional to the square of the current and the resistance of the areas of actual contact.
The amount of heat generated can be so significant that the places of the transfer resistances become very hot. Therefore, if heated contacts come into contact with combustible materials, they may ignite, and contact of these places with explosive concentrations of combustible dust, gases and vapors of flammable liquids will cause an explosion.
To increase the area of actual contact of the contacts, it is necessary to increase their compression forces by using elastic contacts or special steel springs.
To remove heat from the contact points and dissipate it into the environment, contacts with sufficient mass and cooling surface are required.
Thus, to ensure safe working conditions in existing electrical installations
a set of measures should be envisaged to be implemented at all stages - before the beginning, during the execution and at the end of work. Measures are understood as the organization of certain actions in electrical installations (registration of work, appointment of persons in charge, preparation of the place of work, briefings, etc.), as well as specific manipulations with electrical devices (switching switching, checking the presence or absence of extinguishing in live parts, installation of protective earthing and others). In addition, local conditions and areas of application of electrical installations should be taken into account.
Considered causes of fires
are up-to-date. Today, a person cannot do without machines, installations and computers. Every year, as practice shows, the use of electrical installations increases, and the sooner measures are developed and taken to prevent fires, the more secure the future awaits us.
Fire protection measures