tailieunhanh - Industrial Control Wiring Guide 2E Episode 4

Tham khảo tài liệu 'industrial control wiring guide 2e episode 4', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 3. WIRE TYPES AND PREPARATION . Cable strippers The outer sheath of multicore cables has to be removed without damage to the inner cores. There are several types of stripping tool available and although the actual detail differs between types a representative tool is shown here. The cable clamp is spring loaded. The cutter is adjustable for the thickness of outer insulation. Operation Use a spare piece of cable to check adjustments. Adjust the cutter to suit and lock in position. Open up the jaw and place it around the cable. Squeeze the jaw to cut into the insulation. Rotate the stripper to cut the insulation all the way round. Pull off the insulation. Check that no inner core is damaged. 24 3. WIRE TYPES AND PREPARATION . Fault prevention Here are some examples of the damage that can be caused by lack of care when removing insulation. Nicks in solid conductors. Stripped plating and scores in solid metal conductors. Strands cut out of multistrand wires. Strands nicked. These cause the wire to be mechanically weakened and its current carrying capacity reduced. Each of these has the potential to cause the finished equipment to malfunction when it is in service because the wire will eventually break off or even act like a fuse. Summary Hand strippers are a common cause of damage to insulation and conductors so you must frequently check the adjustment and with the so-called automatic type be sure to use the correct hole size. It is all too easy to place the wire into the wrong hole either smaller causing the damage already mentioned or larger which can tear the insulation leaving a ragged edge which may get mixed in with the solder and cause contamination of the joint. Most of these problems can go unnoticed except by you at the time they occur. However remember that they will cause operational problems to the end-user so don t let them pass. Whatever type you are using read the instruction leaflet which the manufacturer provides before using them. If you .