How are the instrument cables and instruments connected?
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Dear teachers, are the instrument cables and instruments in our factory connected through an explosion-proof flexible pipe? Do you think there is any problem? The problem now is that there is water vapor in the meter. For example: inside the cut-off valve feedback box, inside the pressure transmitter, inside the flow meter junction box, how are yours connected? Asking for pictures, asking for pictures of the scene.
Normally, instrument cables and instruments are connected through plugs, sockets or terminal blocks. Explosion-proof flexible conduit is often used to protect cables from mechanical damage and chemical corrosion. If water vapor appears in the instrument, inspection and maintenance are required. It may be caused by loose connections or inadequate protective measures. It is recommended to check and take appropriate measures, such as replacing seals or adding protective covers. When connecting cables, you generally need to use an appropriate plug or terminal block according to the model and specifications of the instrument, and wire it correctly. The specific connection method may vary depending on the type of instrument. It is recommended to refer to the instruction manual of the instrument or relevant standards for operation. The following is an example of a typical instrument cabling diagram: !( https://i.imgur.com/JPkXJN9.jpg) .
The explosion-proof flexible pipe connection shown in your picture is not a big problem, but the one pointed by the arrow feels like it is not tightened.
Seal the cable opening with fireproof mud
The result of blocking it with fireproof mud is that the instrument cover cannot be opened in the end. It is best to install an explosion-proof gland.
This post was last edited by myface on 2023-4-3 15:56. There is no problem in connecting like this. What you need to check is whether the interface is sealed properly. If the seal is not tight, it is actually false explosion-proof. In addition, what is the explosion-proof level or protection level of the instrument itself? Could it be that the meter itself is not tightly sealed and the air humidity is high, resulting in water vapor?
If there is water in it, it may be that the drainage of the bridge is not done well.
This kind of water will usually get in, especially in the south, because the wiring pipe and the meter are connected without any sealing.； It is recommended to add a take-over cable sealing joint at the meter entry
Explosion-proof flexible pipes are used for cable threading protection, but their waterproof performance is not as good as that of explosion-proof gland sealing joints. Therefore, when outdoor or when there is liquid gas in the instrument, even if explosion-proof flexible pipes have been installed, explosion-proof glands must be installed. The sealing, waterproofing, and fixed position effects of explosion-proof glands are better.
The explosion-proof flexible pipe is not explosion-proof. The presence of water vapor on the meter indicates that the cable is not properly locked.