Microprocessor centralization of arrows and signals
Analysis of existing ETS systems and their exploitation experience indicate that the relay system is used and operated for more than 60 years, resulting in a significant increase in the number of fraud
How is frequency measurement performed
Before using a multimeter, and in particular, a frequency meter, you need to carefully read again the parameters that it has the ability to measure. In order to properly measure them you need to master several steps:
Turn on the device with the corresponding button on the case, most often it is highlighted in bright color.
Set the switch to measure ac frequency.
Taking up two probes and connecting them, according to the instructions in the appropriate sockets, we will test the measuring device. First you need to try to find out the frequency of the voltage in a standard 220-volt network, it should be equal to 50 Hz (the deviation may be several tenths). This value is clearly controlled by the electricity supplier, since when it changes, electrical appliancesthe electricity supplier, since when it changes, electrical appliances can fail. The supplier is responsible for the quality of the electricity provided and strictly observes all its parameters. By the way, this value is not standard in all countries. By connecting the frequency meter terminals to the outlet pins, the instrument will display a value of about 50 Hz. If the indicator is different, it will be its error and in the next measurements it will need to be taken into account.
Further, one can safely make the necessary measurements, remembering that only the alternating type of voltage has a frequency, the direct current does not have a variable periodically value.