Insulation and grounding control relay

Relay for monitoring insulation and grounding

Insulation and grounding control relays are used in many industries, in metallurgy, in the IT industry, in hospitals and in means of transport. They are used wherever IT systems merge, that is, isolated systems in which all live parts are either isolated from earth or have one point of the system earthed by high impedance.

Insulation and grounding control relay: characteristics

Insulation and grounding control relay increase operational reliability and user safety. The big advantage of isolated systems is that the devices connected to them can work continuously, even in the event of the first failure, i.e. the so-called earth connection. Then, the phase voltage of the undamaged phase will increase to the value of the phase-to-phase voltage. The first failure must be removed as soon as possible. If you choose insulation and grounding relays from such renowned manufacturers as Siemens, you can be sure that they will perform perfectly in any situation. And it is the indicated operational reliability that guarantees safety. As an indication of the state of an isolated system, the indicated components work very well. The user will be informed immediately if the insulation condition drops below the set value. More detailed examples in which this type of relays are used can be mentioned:

  • production plants,

  • automation systems,

  • control and protection circuits,

  • photovoltaic systems,

  • special applications, for example in tunneling machines,

  • mining industry,

  • DC applications,

  • heavy industry.

It is the indicated relays that determine the degree of security in the indicated places. The insulation and ground monitoring relays communicate with the host computer via a specially designed industrial bus. First of all, their task is to analyze the thermal and current load in isolation transformers. They are used to check safety of single-phase and three-phase insulations in insulated systems, according to top-down standards. They are equipped with displays for displaying the numerical value of the measured insulation resistance. They also have buttons for handling parameter setting to facilitate monitoring and LED signaling. This type of signaling indicates the state of the controlled system.

Insulation and grounding monitoring relay: important parameters

When selecting insulation and earthing control relays, pay attention to such important parameters as: type of electrical connection, type of control voltage, phase sequence control, phase failure control, undervoltage control function, overvoltage control function, phase asymmetry control, number of break contacts, number of make contacts , number of changeover contacts, width, height, depth, voltage measurement range from ... to ..., or rated control voltage. It is worth knowing that one or two built-in signaling relays with a changeover contact allow the connection of an alarm signaling device. The relays available on the market have an optional alarm memory function with the option of canceling the alarm with a button on the relay.

Therefore, for example, local and remote testing of how the individual relays work can be performed without any problem. It also gives some insight into how control will be carried out with the relays used in the future. Please note that no more insulation and earthing relays may be connected to one IT network. The separate supply voltage also allows for the monitoring of the network that is not under voltage. In turn, direct as well as the simplest management of the ground monitoring relays is done via internal web pages, with the help of a browser.