What is an instrument location layout?
Instrument location layout is a layout which indicates the exact location of instrument/junction box, trench/trays etc.
Trench and duct is the path for primary cable and tray is the path for secondary cables. A tray is either made of metals or FRP (Fiber reinforced plastic).
What is Junction box and Junction box location drawing?
A junction box is an intermediate between instrument and control panel. A junction box is an electrical box which contains terminal blocks. The cables from the instruments come to one side of the terminal block and from the other end, it goes to the control panel. As I mentioned in previous post cables from the control panel is called primary cables. Usually, multicore cables are used as primary cable. Cables to the instruments are called primary cables. Usually, single core cables are used as secondary cable.
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| Terminal block |
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| Typical example of a junction box |
What is the purpose of a Junction box?
Purpose of a Junction box is to give convenience and protection for cabling between instrument and control panel. In maintenance point of view, a junction box is very much important. It helps very much in troubleshooting. Below I am giving an example of Junction box location drawing.For proper entry of cables to the JB, Jb arches are used. Cables are entering to the JB through cable glands. The cable gland is used for the proper placing of cable. Different types of cable glands are available.
