When installing electrical wiring or electronic communications, it is imperative to make nodal points at which transitions from one bus to another or branching from the main line take place in directions leading to specific objects or electrical appliances. Such places must first of all be safe and reliably protect the connected contacts from environmental influences. For these purposes, junction boxes have been developed.
What are junction boxes
Plastic junction box (or metal) is a box of round, square or rectangular shape, equipped with holes for entering electrical cables. The main task of the product is to protect the wiring of wires, which can be interconnected inside by soldering, twisting or using terminal blocks. The received withdrawals are forwarded in any direction.
Junction boxes for outdoor installation belong to the group of electrical installation equipment. Their specificity suggests the presence in such deviceselements responsible for the tightness of the connections inside. So, they are equipped with gaskets, couplings that prevent moisture from entering the case through the inlets and the cover.
Scope of application
The area where the junction boxes can be used concerns the supply electricity and electrical signals that are transmitted using wires. Therefore, there are several types of them:
- Conventional electrical distribution - designed to carry out the wiring of supply voltage wires in domestic and industrial conditions. These boxes can also be used for direct current.
- Telephone, computer, for signaling - they are bred stranded tires. They are usually provided with terminals and a tamper-proof system.
- Junction boxes for outdoor installation for high-frequency and microwave equipment. It is possible not only to solder wires in them, but it is also possible to install small circuits. The case is necessarily shielded, and the contents are sometimes filled with a waterproof compound if the equipment is operated in conditions of high humidity.
Wiring box classification
Outdoor junction boxes are divided into several categories.
Material:
- Polymer - polyethylene, polypropylene, polystyrene cases.
- Metal - made of tin or aluminum and its alloys.
Destination:
- Household - forbreeding electrical wiring, where single-phase networks are used.
- Industrial - high-strength mini-boxes where three-phase voltage wires are bred.
- Special - outdoor junction boxes for wiring signal cables of pulse, radio frequency and microwave technology.
Installation method:
- Open type - wiring runs outside the surface.
- Hidden type - the cables are hidden inside the strobe.
Security level:
- IP44 - boxes that can be used outdoors under cover from direct rain, dust, in rooms with a humid environment.
- IP55 - boxes that can withstand short-term direct contact with water and do not let dust through. The most popular type of distribution equipment.
- IP65 - designed for installation in places highly exposed to the atmosphere, do not let rain water and dust through.
- IP67 - can be kept in a humid environment for a long time, for example, underground or on its surface.
- IP68 - able to protect wiring under water. They are designed for shallow depths.
Designs of junction boxes
All electrical wiring junction boxes share the same basic design, but there are some differences in detail.
Surface mount boxes include:
- Square, rectangular or round box with holesfor side wiring, cover screw entry threaded bushings, DIN rail mounting bushings, and holes for surface mounting.
- A lid equipped with a channel for sealing rubber and holes for mounting screws to the box. The technical parameters of the product are usually indicated on its outer surface.
- Glands for cable duct or wire entry.
- Four cover screws.
- Sealing gum.
- DIN rail for connecting wires (not available on all models).
- A security button that is connected to an alarm to prevent unauthorized access (only available on special purpose models).
Outdoor mortise-type boxes differ from those described above in that there are no sealing gums and glands, since the entire surface is hidden under a layer of putty, which, being moisture resistant, itself provides hermetic protection.
In metal boxes, cable channels are inserted through threaded fittings. They more reliably protect connections from atmospheric influences. Such products do not need to be shielded.
Connection of junction box
To install the wiring box, you will need the following installation tool:
- Electric drill with impact function.
- Pliers.
- Slotted and slotted screwdriver.
- Mounting knife with interchangeable blades.
Additional items:
- A roll of duct tape.
- Screw terminals electrical.
- Mountingmaterial (self-tapping screws, plastic dowels).
The installation procedure for the outdoor wiring junction box is as follows:
- Holes are drilled at the installation site for attaching the box to the plane, dowels are driven in.
- Holes are cut in the glands with a knife for the desired wire diameter.
- The electrical terminals are screwed inside to the desired number of contacts.
- The box is attached to the wall with self-tapping screws, screwing them into dowels.
- Wires are inserted through the holes in the glands.
- Smooth the ends of the wires from insulating material and remove the oxidation layer, if present.
- Assemble the circuit in the junction box, fixing the wires in the appropriate terminals.
- Close the lid of the box, fixing it with threaded screws.
Benefits of using junction boxes
The ease of use of mounting boxes is well founded:
- Products are produced for different power lines.
- Provides a high degree of contact protection with the right choice of device type.
- No hassle of mounting the case and connecting wires.
- Wide range of shapes and decorations, such as wood look outdoor junction boxes.
- Ability to access communications and reconnect.
- Design durability.
Conclusion
Despite the ease of installation of junction boxes, it is important to remember that only electricians and electronics engineers have access to this type of activity when it comes to signal wiring!
