Circuits. Flashcards
- Min size for branch circuit wire?
14 AWG.
- How many sq. ft. min for 1 general purpose circuit ?
500 sq. ft.
- Max distance along wall to receptacle?
6 feet.
- Min wall length for receptacle?
> =2 feet.
- Min hallways length for receptacle?
10 feet.
- Circuit for bathroom?
Separate 20A ckt for bath receptacles or dedicated 20A ckt to each bathroom.
- Laundry circuit?
Min 1 20 A circuit to receptacle.
- How must the black and red wires originate in a 3-conductor Romex cable?
From different poles or the neutral can be overloaded because it carries the sum of the currents.
- How is common3-wire circuit run to a duplex receptacle for the dishwasher and the garbage disposer?
By breaking the connecting tab on a duplex receptacle each half can be fed by separate circuits with 240 V potential between the circuits. Each half can be fed by separate circuits with a shared neutral.
- Receptacle rules for kitchen countertops?
- All individual counter spaces >= 12 in. require receptacle.
- Spacing so no point >= 24 in. from receptacles.
- Max 20 in. above countertop.
- Island and peninsula counter spaces min 1 receptacle.
- What must be also considered in determining the ampacity of a wire?
The ambient temperature.
- How shall You size Motor circuit?
- Use name plate FLA only for overload protection size.
- Find FLC from hp and voltage in table.
- Size circuit conductor to 125% of FLC (full-load-current).
- Size breaker 259% FLC.
- Size TD (time delay) fuse 175% FLC.
- Protection NM cable?
1/16” steel plate, if closer than 1-1/4” to framing surfaces.
- How is AC cable (BX) grounded?
Armor is EGC - don’t bring bond wire into box.
- How is MC cable grounded?
By green wire. Metal armor is not a ground.
- Max voltage drop?
- 3% on a branch circuit.
2. 5% overall voltage drop including the feeders.
- How can You overcome a voltage drop problem?
- Use larger wire than the minimum size and make sure that all connections are tight.
- Use fewer than the maximum number of outlets on each circuit.
- What is used to maintain clearance from cable to stud or joint edge?
Stand-off clamp.
- How can You protect cable within 6 feet of scuttle?
Boards protect cables.
- How can You protect Romex cable under the floor?
- > = 3/8 Romex clamp to joists.
2.
- Max bends between raceway pull points?
360* max.
- What raceway can be bury in soil?
RMC (Rigid metal conduit).
EMT (Electrical metallic tubing) not OK.
- 2 way to run 3 way switch circuit?
- 2 wire g Romex supply 120 V to 3 way switch, 3 wire g Romex run to another 3 way switch, 2 wire g Romex run to fixture box. All neutral interconnected.
- 2 wire g Romex bring 20 V to fixture box, 2 wire g Romex run to 3 way switch, white is connected to hot and black to neutral, 3 wire g Romex run to other 3 way switch. White is reidentifyed in each box.
