1. The bridge should not be installed directly below the water pipe. The sprinkler head is too close to the bridge, and water will be sprayed inside the bridge. The bridge is laid above the steam heating pipeline without protective measures.
Correction: Maintain a safe distance between the bridge and the sprinkler head. It is not recommended to lay cable trays above thermal or corrosive gas pipelines and below laying liquid pipelines.
2. The fireproof sealing of the bridge crossing the wall and floor is not tight, and the conductive part of the shell is not connected to the grounding bus.
Correction: Fireproof and blocking measures shall be taken for bridges laid in shafts and crossing different fire zones according to the design requirements. The fireproof plugs of the bridge should be on the same plane inside and outside, and the fireproof plugs between the cables inside the bridge should be tight and seamless.
3. The two ends of the connecting plate between the galvanized box bodies are not connected to the ground wire.
Correction: The two ends of the connecting plate between the bodies of the galvanized trough box should be jumper grounded. However, at least two connecting and fixing bolts with locking nuts or washers shall be provided at both ends of the connecting plate.
4. The expansion joint of the Shandong cable bridge was not firmly fixed using a connecting plate, and the grounding jumper connection was incomplete. The two sides of the expansion joint were installed asymmetrically with supports and hangers for fixation.
Correction: Fix the expansion joint of the bridge firmly using a connecting plate, connect the grounding jumper wire perfectly, and install supports and hangers symmetrically on both sides of the expansion joint for fixation.
5. Half of the connecting parts are set in the wall, which is inconvenient for installation and maintenance, and the grounding jumper cannot be connected
Correction: Reserved openings should be reserved in advance at the places where the bridge passes through the wall and floor slab. The bridge should pass through the openings and should not be in direct contact with concrete and mortar. A certain gap should be left at the places where the bridge passes through the wall and floor slab. The connection part of the bridge should be set outside the wall for easy installation and maintenance.
6. The metal hose is not connected to a ground jumper.
Correction: Metal cable trays and their supports, as well as metal cable conduits introduced or led out, must be reliably grounded (PE) or connected to neutral (PEN).
7. The steel pipe is grounded to the bridge, and the jumper conduit is not grounded to the bridge.
Correction: Set a grounding jumper between the jumper conduit and the bridge, and unify the grounding jumper position, wire length, and grounding clamp orientation of multiple conduits.
Several error-prone practices during bridge construction are explained in seven aspects. Do you have any requirements for this? Can follow our website http://www.yeeones.com Consulting anytime, anywhere!