Grounding devices for the protection of medical equipment - tomographs, x-ray machines and other highly sensitive equipment - should provide low resistance. The documents for such equipment often indicate that the required resistance for it should not exceed 2 ohms. The ZANDZ Technical Center recently received a request to achieve this level for one of the hospitals. We proposed to use a large number of grounding electrodes with a length of 6 m. Let's study this solution in more detail.
Calculation example of grounding for the hospital medical equipment
Object: Hospital in Moscow.
Perform a grounding device for the hospital, providing the resistance of not more than 2 ohms
A set of measures to ensure the necessary requirements for the grounding system of the hospital medical equipment:
1. Grounding is made in accordance with the EIC 7th ed.
2. Installation of a grounding device consisting of 10 vertical electrodes 6 m long united by a horizontal electrode (copper-bonded tape 30x4 mm). The distance from the horizontal electrode to the facility shall not be less than 1 m, deepening 0.5 - 0.7 meters.
Hospital's grounding device resistance calculation:
The design resistance of the grounding device is 1,96 Ohm..
Figure 1 shows the arrangement of equipment.
Table 1 gives the list of the required equipment and materials.
Подключить к главной заземляющей шине – connect to the main grounding bus
Электрод - electrode
Полоса омедненная 30 на 4 – copper-bonded tape 30 to 4
Table 1 - List of equipment and materials for hospital grounding.
|№||Fig.||Product item||Name||Quantity, pcs|
|1.||ZZ-001-065||ZANDZ Copper-coated threaded grounding rod (D14; 1.5 m)||40|
|2.||ZZ-002-061||ZANDZ Threaded coupler||31|
|3.||ZZ-003-061||ZANDZ Starting tip||10|
|4.||ZZ-004-060||ZANDZ Driving head for a jackhammer||8|
|5.||ZZ-006-000||ZANDZ Conductive grease||4|
|6.||ZZ-008-000||ZANDZ Header for a jackhammer (SDS max)||1|
|7.||ZZ-005-064||ZANDZ Clamp for connecting conductors (up to 40 mm)||14|
|8.||ZZ-007-030||ZANDZ Waterproof tape||4|
|9.||GL-11075-50||GALMAR Copper-bonded tape (30 * 4 mm / S 120 mm²; coil of 50 meters)||1|
|10.||GL-11075-20||GALMAR Copper-bonded tape (30 * 4 mm / S 120 mm²; coil of 20 meters)||2|
Any questions about hospital grounding? Please contact our ZANDZ Technical center!!