tool box
Wire Colour Codes
Q: What wire colours are used for 415V 3-phase AC?
L1 = Red
L2 = Black
L3 = Grey
Neutral = Blue
Earth = Green/Yellow
Q: What colours are used for 240V 1-phase AC
Live (L1 or Phase) = Brown
Neutral = Blue
Earth = Green/Yellow
Q: What is the wire colour for 110V DC?
Black
Q: What is the wire colour for 110V AC?
Grey
🔧 Flashcard 2:
Panel Wiring & Earthing
Q: What wires are used in panel wiring?
1.5mm² and 2.5mm² tri-rated white wire
Q: What is used for earthing panels?
1 x 75mm² tri-rated wire
50x4mm or 50x6mm earth tape
Cable Types
Q: What is a Cleveland multi-core cableS
XLPE insulation, LSZH sheath, armoured, black outer
For mains, control, and fixed wiring
Sizes: 1.5mm² to 16mm²
Voltage: 600/1000V
Q: What are telephone cables made of?
Tinned copper
LSZH insulation
Standard: ESI 09-6 Section 4.5
Cable Function Use
Q: What are multi-core and panel cables used for
Control panels
Switchgear
CTs and VTs (protection and metering)
AC/DC supplies
Alarm circuits
Tap changers
Remote indication
Crimp Colour Codes
Q: What are the crimp colours and sizes?
Red = 1mm² – 1.5mm²
Yellow = 1.5mm² – 2.5mm²
Blue = 4mm² – 6mm²
Q: What colours are used for CT and VT ferrules?
CT = Red ferrule (IDs A, B, C, D)
VT = Yellow ferrule (IDs E, F, G)
Telephone 20-Pair Colour Codes
Q: What are the 4 base wire colour pairs in a Cleveland 20-pair cable?
White/Blue
Red/Blue
Black/Blue
Yellow/Blue
Then matched with:
Orange, Green, Brown, Grey
Cable Gland Sizes
Q: What gland size fits 2c–4c 2.5mm² or 5-pair cable?
A:
20s
Q: What gland size fits 7c 2.5mm² or 10-pair?
A:
20L
Q: What gland size fits 12c or 20-pair?
25mm
Q: What gland size fits 19c–27c
32mm
Q: What gland size fits 37c 2.5mm²?
40mm
Tap and Drill Sizes
Q: What drill size do I need for a 6mm tap?
A:
5.5mm drill
Q: What drill size is used for 10mm tap?
A:
8.5mm drill
(Other sizes also:
4mm tap = 3.5mm drill
5mm = 4.5mm
8mm = 6.8mm
12mm = 10.2mm