RU104394U1 - DEVICE FOR SEPARATING THE CIRCUIT PROTECTION OF ANODE EARTHING AND THE PROTECTIVE EARTHING AND LIGHTING PROTECTION CIRCUITS - Google Patents

Abstract

 A device for separating the anode ground loops of the cathodic protection and the protective grounding and lightning protection loops made on power varistors, characterized in that it comprises a heat dissipating insulating body with power varistors connected in series and in parallel, a lead to the drainage point of the tank, a lead to the ground loop and bolt connection .

Description

The utility model relates to the field of energy saving and increasing efficiency in the electrical protection of underground structures and vertical steel tanks (PBC) from soil corrosion.

There is a known system for protecting reservoirs and pipelines whose main drawback is the excessive consumption of electricity to protect underground metal structures. It is known that each tank system has its own lightning protection and protective grounding system connected to a common grounding and lightning protection circuit (Fig. 1). Since both the anode protective earth and the protective earth circuit are securely attached to the protected structure (according to the existing rules of clause 7.1 [Elecgric Bible [Text]: PUE sixth and seventh editions, all applicable sections]; MPOT; TPE. - Novosibirsk: publishing house , 2007 - 606 s, Il, Ch. 2.7 and 2.8]). then there is an electrical connection between them. Moreover, the protective current from the anode ground flows not only to the PBC, but also goes into the ground loop and lightning protection. With closely located drainage points and places of connection of protective grounding and lightning protection loops to the metal structure, this effect is especially noticeable. This leads to an increase in current loss, and, consequently, an excessive consumption of electricity. The known lightning protection system contains a ground loop, consisting of several steel vertical and horizontal ground electrodes. Grounding conductors are connected to the protected object through a down conductor, and are located in the ground. Execution of connections is welding or reliable bolted. The existing circuit is shown in figure 1.

The prototype of the device for separating the ground loop from the protected structure is a nonlinear surge suppressor (SPD) connected in parallel with the protected structure [Electrician’s Bible [Text]: ПУЭ (sixth and seventh editions, section 2 of Chapter 2.5. Surge protection, grounding). In normal operation the varistor has great resistance and does not affect the electrical processes occurring in the circuit in any way, but as soon as the value of the current, and, consequently, the voltage applied to the electrical equipment , will exceed the maximum permissible value, the varistor is triggered, its resistance instantly decreases, and most of the emergency current flows through the varistor circuit, without causing damage to the electrical equipment.

The objective of the utility model is to save energy and increase the effectiveness of anticorrosive electrochemical protection (ECP) of RVS and underground metal structures.

This task is achieved by means of a device for separating the anode ground loops of the cathodic protection and the protective grounding and lightning protection loops made on power varistors, while it contains a heat dissipating insulating body with power varistors connected in series and in parallel, output to the tank drainage point, output to the circuit grounding and bolt connection.

The drawing of figure 2 shows a diagram of a device for separation of circuits, consisting of the output to the drainage point of the PBC 7, the output to the ground loop 2, heat dissipating housing from the insulator 3, a set of varistors 4, and a bolt connection 5.6.

The utility model works as follows. Consider the circuit ECP using a device for the separation of circuits (figure 3). When a rectified direct voltage is applied from the positive terminal of the cathodic protection station (RMS) 5 through the drainage anode line 7, the current 15 from the anode earthing switches 11 starts to flow through the trough electrolyte towards the protected structure 10, that is, the PBC. The flow of current 15 is ensured by the fact that the negative terminal from the RMS is connected through the connecting cable P and the drainage point 12 to the protected structure. those. a potential difference is created between the anode grounding conductors 77 and the PBC 10.

Because in the absence of device 14, the RVS is electrically connected to the protective grounding circuit and lightning protection 16 through the drainage point 13, then the negative potential from the RMS polarizes not only the protected structure, but also the protective grounding circuit, which reduces the efficiency of cathodic protection and leads to large energy losses. The introduction of device 14 will avoid these losses.

A device for separating the anode ground loops of cathodic protection and the protective ground loops and lightning protection loops has the following properties:

- the device is an insulating insert and does not allow relatively small currents from cathodic protection installations;

- when the RVS falls into the zone of action of large currents (such as those arising from lightning strikes), the device “opens” and connects the RVS to the lightning protection circuit, which prevents the emergency consequences of a lightning strike.

All these properties are due to the presence of power varistors, the current-voltage characteristic of which is presented in figure 4.

It is also necessary to understand that the supply pipe to the RVS must be replaced with an insulating insert of the appropriate diameter, otherwise the protective current will leak through it and the grounded valve body of the valve

Claims (1)

A device for separating the anode ground loops of the cathodic protection and the protective grounding and lightning protection loops made on power varistors, characterized in that it comprises a heat dissipating insulating body with power varistors connected in series and in parallel, a lead to the drainage point of the tank, a lead to the ground loop and bolt connection .