7.2　General Items

7.2.1　The installation of foundation steel shall be in accordance with the following requirements:

1　The allowable deviation shall be in accordance with those specified in Table 7.2.1.

Table 7.2.1　Allowable deviation for installation of foundation steel

2　The top of foundation steel shall be 10mm higher than the smoothed floor after the foundation steel is installed.The handcart switch cabinet shall meet the technical product specification.The foundation steel shall be connected to grounding main line and grounded securely at two or more points securely.

7.2.2　Where the panels and cabinets are installed separately or in line，the deviation of their verticality and levelness，surface difference between the panel and cabinet，as well as the joint between the panel and cabinet shall be in accordance with those specified in Table 7.2.2.

Table 7.2.2　Allowable deviation（mm）for installation of the panels and cabinets

7.2.3　The connection between the conductive contact surface of equipment inside the panels and cabinets and the bus outside must meet the requirements in Article 12.2.1 of this code.The switchboard，switchgear and the equipment in them shall be connected with all components securely with locking mechanism.Where the panels and cabinets are installed at a place with vibration，the measures against vibration shall be taken to in accordance with design requirements.The master control panel，relay protection panel and automatic device panel shall not be welded to the foundation steel tightly.

7.2.4　No additional strain shall be caused to the connection of silicon rectifier cell with external devices.

7.2.5　The handcart and drawer switch cabinets can be pushed and pulled freely without sticking.The moving contact shall be on the same center line with fixed contact，and be able to contact the fixed contact tightly.When pushed in，the grounding contact shall contact before the main contact，and when pulled out，the grounding contact shall disconnect after the main contact.

7.2.6　The high voltage switchgear shall be in accordance with the relevant requirements in Chapter 3 of this code.The surface of high voltage ceramic parts shall be free of crack，defect and enamel damage and other flaws.

7.2.7　All of the wires of secondary circuit in the panels and cabinets shall be correctly and securely connected with complete and clear makings.The insulation of them shall meet not only the relevant requirements，but also those specified in Article 20.2.9 of this code.

7.2.8　The paint coat on the panels and cabinets shall be in good condition without damage.The anticorrosive coating bracket and other parts for fixing the electrical equipment shall be in good condition.The colors of panels and cabinets installed in the same room shall be in perfect harmony.

7.2.9　The terminal box and the operation box shall be securely and reliably installed，well-sealed and protected from moisture and dust.They shall be installed in such place that they are easy to be checked and operated.They shall be arranged in order when installed in line.

7.2.10　The operation box and power switch cabinet and other equipment that are installed outdoors shall be provided with rain protection device.The inlet cables shall be let in through the bottom of the box or cabinet.The installation height of the operation box should be set in such a way that the center of the box is 1.5m above the floor.The floor-mounted switch cabinet shall be securely connected to the channel steel of foundation.