Рет қаралды 12,396
A short video review of the level switch PZ-818.
It is designed to control and maintain a given level of conductive fluid, as well as to control the electric motors of pumping units.
The principle of operation of the relay is the following: the relay has remote sensors that, when immersed in a liquid, create a closed circuit. In the complete set with the relay there are three sensors - for the control of two levels. The relay itself can operate in two modes - filling or emptying the reservoir with liquid. If the filling mode is selected and the liquid level falls below the minimum, the relay gives a signal to the pumping unit for filling, when the maximum level is reached, the filling signal is removed.
If the emptying mode is selected and the liquid level in the tank reaches the maximum, the relay gives a signal to the pumping unit to empty the tank, when the minimum level of the relay is reached, the pump installation is disconnected.
Due to the fact that the relay has the function of adjusting the switching time of the executive contact, the user has the opportunity to switch off the pumping unit not immediately, when the set level is reached, but with a slight delay, which allows to avoid false alarms when the liquid level is perturbed, and also to optimize the operation in a specific application relay.
To prevent undesired activation under the influence of extraneous factors (for example, sensor contamination, humidity, specific liquid composition), you can adjust the sensitivity of the level control relay according to the conductivity of the monitored liquid - from 5 to 150 kOhm. Moreover, this relay allows for a separate adjustment of the sensitivity by levels, which is convenient in the case when the controlled liquid has different density components, for example, sewage.
This type of relay allows automation of the control of the supply or discharge pumps, monitoring of fluid leaks and controlling the supply of fluid until the leaks are eliminated, maintaining a predetermined level of liquid in the tanks, protecting the downhole pumps from "dry running".
Due to the fact that the sensor terminals are not galvanically connected to the supply circuit, the relay is safe to use in the household, for example, filling the reservoir for irrigation or the shower in the country.
This level switch for its operation can use both complete remote sensors and others, for example, already built in the reservoir conductivity sensors, as well as sensors with mechanical contacts, for example, float type.
Setting the relay is reduced to setting the sensitivity by levels, the time delay of switching contacts, as well as selecting the operating mode - pumping or filling.
More information on the site fif.by/catalog...