LIGHTING PROTECTION AND GROUNDING OF A CONDENSER COMPARTMENT

The technological cycle of many industries includes cooling products in a refrigeration unit. To set low temperature in the rooms, special condenser compartments are used. Lightning protection and grounding of one of such objects was performed by the ZANDZ Technical Center.

Consisting of capacitors, fans, receivers, pumps, pipes and automation that controls all this equipment, the condenser compartments need reliable lightning protection, better to say "subtle".

According to the task of the customer, it was required to protect the platform with capacitors installed on it from lightning. Due to the fact that the entire site is made of metal, the most successful place for installing lightning rods was its metal columns. Having placed four lightning rods 8 m high on them, it was possible to ensure reliable lightning protection of the capacitor compartment.

Find out more about the solution offered to the customer from the news text.

Task

Calculate lightning protection and grounding of the capacitor compartment.

Solution

Calculations of lightning protection are made in accordance with the following documents:

1. "Electric Installation Code" EIC 7th ed. (hereinafter - EIC).
2. "Instructions for organization of lightning protection of buildings, structures and industrial communications" IS 153-34.21.122-2003 (hereinafter IS).
3. "Instructions for lightning protection of buildings and structures" AD 34.21.122-87 (hereinafter - AD).

Lightning arresters are used for protection of structures from lightning strikes. A lightning arrester usually consists of a lightning rod, intercepting the lightning strike, a down conductor and a ground electrode. All these elements allow to safely drain lightning current into the ground without a damage for the protected object.

A condensor compartment refers to traditional structure in terms of lightning protection according to IS and belongs to category 3 according to AD.

Description of the external lightning protection system of the capacitor compartment

The set of measures to provide the required lightning protection is offered by the following solutions:

1. Installation of 4 rod lightning rods 8 m high, attached to the columns of the site. It was taken into account that 1.5 m of the height of the air terminal is taken for fixation.
2. In accordance with clauses 1.6 and 2.12 of the AD, metal structures of the site for capacitors are used as down conductors.
3. In accordance with clauses 1.8 and 2.13 of the AD, a natural grounding conductor- the foundation of the building, is used as a grounding conductor.

The layout of elements in the lightning protection system and the grounding device is shown in Figure 1. Protection zone corresponds to zone B of the AD.

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