Splicing and terminating (low voltage) Flashcards
list 4 common classes of of terminations/connections
- soldered
- fused
- mechanical
- compression
What is exothermic welding most often used for?
For connecting grounding and bonding conductors.
True or false? Compression connections are considered to be of the nuts and bolts type.
False
True or false? The soldering process is used to tin stranded conductors.
True
What methods should be used to remove insulation from a conductor
penseling and stripping with appropriate tool for the cable
True of false? Insulation should be removed from a conductor by ringing the insulation at 90 degree to the conductor.
false
What problems can a scored conductor introduce.
It can break & can have its section reduced
What is the key feature of a tool designed to remove the outer sheath of a multi conductor cable?
It must remove only the sheath without damaging the insulation of the underlying conductors OR it must remove the insulation without damaging the underlying conductor itself.
What four properties must be considered when selecting splicing insulation material
- Max. voltage
- Max. temperature
- Material and form of the cable
- Environmental conditions
Name 4 materials that can be used to reinstall a spliced conductor.
- Tapes
- Heat shrinkable tubing
- Preformed insulating covers and boots
- Splicing compound
List the 3 types of wire or cable connections.
- splices
- taps
- terminations
What is a splice?
The joining of two or more conductors of the same size and ampacity.
What is a tap?
The joining of two or more conductors with a conductor of a smaller size and ampacity.
What is a termination of a conductor?
The final destination of a conductor at a control or utilization device.
What is the maximum size conductor that CEC allows to be terminated under a screw without the use of a mechanical or compression connector?
10 AWG
In which direction must a conductor wrap around a wire binding screw for proper termination.
clockwise
What must be considered when selecting a compression tool and die to attach a compression terminal to a conductor?
It must be the correct tool, recommended by the manufacturer.
In which direction must twist-on connections be twisted?
clockwise
Why may you require file when using a split bolt to make a splice?
Sharp edges must be filed.
What is important to remember when terminating stranded conductors?
To confine all the strands in the terminal.
Set screw type wire connectors are often used when either of these two conditions are encountered:
- When the connection must be taken apart many times.
2. When vibrations may affect the connection.
List 4 problems relating to aluminum conductors.
- Oxidation
- Cold Flow
- Thermal Expansion
- Galvanic corrosion
What makings must be on a receptacle if it is used with aluminum conductors?
CU/AL or CO/ALR
How must an aluminum conductor be terminated under a wire binding screw?
3/4 of the way wrapped in clockwise direction.
What danger is there when removing the insulation from aluminum conductors?
They could be easily scored and broken.
What type of compound must be used when making aluminum conductor connections?
Anti-oxidant
When making open air connections between aluminum and copper conductors, which conductor must be underneath and why?
Copper must be underneath, in order to prevent copper oxide salts from flowing onto aluminum and causing corrosion.
