Pipeline / gas boiler grounding together with the installation of the RCD - a necessary and compulsive condition when connecting gas to the single-family house. Beside the standard one, these measures: protection of human and electrical equipment from dangerous voltage and current, are intended to protect against fire and explosion.
Therefore, more severe requirements are applied to the quality of the gas boiler / pipeline grounding as compared with a conventional repeated house protective grounding.
Modern technologies allow you to quickly and easily build an effective grounding, which will serve for a long time without maintenance and repair.
For the construction of the pipeline / gas boiler grounding with the required quality (grounding resistance), it is recommended to use a universal set of modular grounding ZZ-000-015 Mounted in the form of one electrode (point grounding).
Such installation allows to get good quality grounding on a compact area (0.5*0.5 m) in the basement, a storage space underneath or near house, without disturbing lawns and covering.
Ready-made grounding kits are just recommended sets. In each individual case, it is possible to make your own set of individual components in the required amount.
Grounding quality requirements
Grounding resistance, used to connect a gas boiler / gas pipeline, should be:
- in the ordinary clay soils less than 10 ohms (With line voltage of 220 V of a single-phase current or line voltage of 380 V of a three-phase power supply (EIC 1.7.103; for all repeated groundings))
- in sandy soil less than 50 ohms (With line voltage of 220 V of a single-phase current supply or line voltage of 380 V of a three-phase power supply (EIC 1.7.103; all repeated groundings, for soils with resistance of more than 500 Ohm * m)
Specialized documents refer to the EIC (items 1.7.103 and 7.1.59 of EIC (the latter is less "demanding"))
- SNiP 31-02-2001
- SNiP 42-01-2002
- Set of rules 42-101-2003
- Regional construction norms 41-312-2004 (for Moscow region)
Despite the fact that item 1.7.103 of the EIC describes less severe standards for the resistance of each of the repeated groundings (in usual ground - less than 30 Ohms) - representatives of gas companies require to perform grounding resistance not more than 10 Ohms in normal soil.
This requirement is reasonable and is connected to the widespread phenomenon: lack of repeated grounding of each air line pole.
Thus, to compensate any breaches from the side of the power line - it is necessary to ensure that the grounding resistance not more than 10 ohms on the spot and therefore to fulfill the requirement of the EIC on general spreading of groundings of all repeated groundings of the PEN conductor of each air line.
Comment of the specialist
the EIC itself (reminder):
1.7.103. The total resistance to spreading of groundings (including natural ones) of all repeated groundings of PEN-conductor each air line at any time of the year must be not more than 5, 10 and 20 ohms, respectively, at linear voltages of 660, 380 and 220 V of a three-phase current source or 380, 220 and 127 V of a single-phase power source. At the same, the resistance to grounding spreading of each of the repeated groundings should be not more than 15, 30 and 60 ohms, respectively, under the same voltage.
According to this paragraph, the total resistance of grounding poles, houses and other equipment after the "transformer", should be less than 10 ohms. But the resistance of each "customer" of repeated grounding should be not more than 30 ohms. Grounding of our gas system is such EVERY repeated grounding. And it seems we need to make it 30 Ohm.
However, The selection committee will measure the TOTAL resistance of the grounding, not every ground conductor. Since our poles are often not grounded and nothing but the grounding of the gas equipment in many houses is done, it turns out that the total resistance of all ground conductors, which must be no more than 10 ohms, will be equal to the resistance of our "repeated earthing" of the gas equipment.
Therefore, our grounding must be less than 10 ohms.
Special thanks to Alexey Shakhov, participating in the preparation of the material of this page.
Installation of protective devices
We want to draw your attention to the fact that grounding of a house / garden - is just one of several necessary measures for the organization of a high-quality power supply system in the house. Using of grounding without protective devices (eg RCD) - is DANGEROUS.
Connecting grounding to an electric board
|||UNTRANSLATED_CONTENT_START|||Соединение производится медным проводником рекомендованным сечением 16 - 25 мм2.|||UNTRANSLATED_CONTENT_END||| For example, a special grounding conductor can be used.
|||UNTRANSLATED_CONTENT_START|||Прокладка заземляющего проводника в грунте производится на глубине 0,5 - 0,7 метра в заранее подготовленный канал (в который также производится монтаж электродов).|||UNTRANSLATED_CONTENT_END|||
A special clamp is used to connect the grounding electrode to the conductor (included in the kit).
A detailed description of all the mounting steps is available at a separate "Installation of Grounding" page.