Ford Fokus>> Electric equipment>> The basic concepts>> Measurement of pressure, current and resistance
In specialised shops there is a sufficient choice of electric devices. We will get acquainted with some of them.
Control lamp (with needle contact). With its help you can define, whether there is a pressure in the given chain. Be careful: the control lamp consumes a lot of energy, therefore it does not approach for check of electronic systems, for example, the engine management block. Here testers of pressure with light-emitting diodes can be applied.
Tester of pressure with light-emitting diodes. The tester measures pressure in a range from 6 to 700 V.Pokazanija are visible on the digital display. Simple devices are available on sale at the price from 10 euros.
Multimeter — a universal measuring instrument. They can measure pressure, constant both an alternating current and resistance. Suitable devices with the digital display are available on sale at the price from 20 euros. Devices have the independent power supply.
To measure, for example, pressure of the storage battery, attach a wire (as a rule, black colour) the measuring device with a clip having marks «–», to the negative plug «31» storage batteries, and a wire with marks «+», (as a rule, red colour) — to the positive plug of the storage battery. If the device shows only 10,4 In, it means that one of battery accumulators has defect. Check up value of pressure of the battery during start-up if it makes 5 In, the battery means is discharged.
Current strength measurement
For this purpose it is necessary for you to interrupt an electric chain. Separate a contact socket and connect the device to contacts. It is necessary to know that such consumer as, for example, the starter uses the considerable current, therefore the used device should correspond to a current strength of a measured chain.
By means of a multimeter you can measure internal resistance of electric elements.