Auto Electrical Parts
Audible Warning Devices Horns , Buzzers, Bleepers |
Adhesive Tape and Velcro Insulation tapes , Wiring Harness tapes |
BATTERY LEADS Manufactured Battery, Solenoid, and Earthing Cables |
Battery Terminals and Covers Positive Terminal Clamps, Negative Terminal Clamps Battery terminal covers |
Box Assortments Workshop Supplies |
Cable Sleeving Conduit , Heatshrink tubing |
Cable Ties and Cable Clips Zip clips, P clips, Chassis clips |
Cables and Wires Single core cables , Multicore cables for Automotive use |
Block Connectors |
Crocodile Clips Battery clips, Alligator Clips, Jumper cable clips |
Drill Bits Metric & Imperial HSS Drills |
Exhaust Accessories Exhaust U Clamps, Exhaust pipe repair joiners |
First Aid Kits Eyewash Safety Station |
Fuse Boxes & Holders Mega Fuse , Midi Fuse Holders, Blade fuseholders , Fuse Boxes |
Fuses ATO Blade Fuses, Miniblade fuses, Midi Fuses, PAL Fuses, European
Continental and Japanese Vehicle Fuses, Mega fuses |
Grommets Plain and Holed Rubber wiring and sealing grommets |
Hoses, Tubes and Filters Heater hose , Fuel Hose, Fuel Filters |
Hose Clips and Hose Menders Coolant pipe joiners |
Jump Leads Heavy duty jump leads and battery booster cables |
Lights and Bulbs 12v 24v Headlight bulbs, Sidelight bulbs , Worklight bulbs,Indicator
bulbs, Capless bulbs |
Lucar Terminals Uninsulated wiring terminals for modern , vintage and classic vehicle
harnesses |
Threaded Rods, Nuts and Bolts Metric , Imperial, Screws, Fasteners |
Plugs and Sockets DIN Plugs, Lucas Alternator Plugs, Cig Lighter plugs , |
Protective Clothing, Health and Safety Goggles , Visors, Aprons, Nitrile and Latex disposable inspection
gloves |
Rivets Countersink |
Screws Pan head, Posi, Flat, Philips, Tek |
Switches Push pull switches, Toggle Switches, Push switch, Rocker Switch |
Terminals and Connectors Red terminals , Blue Pre insulated terminals,Yellow Preinsulated
terminals, Ring terminals , Bullet terminals, Socket terminals, Spade
terminals, Butt connectors |
Wiring Tools Cable terminal crimpers , Side cutters |
Voltage Converters and Relays |
Washers Plain washers, Flat Washers, Body washers, Spring Washers |
Towing Accessories 12N , 12S, 7 pin, 13 pin, 24N, 24S, Plugs
Sockets, Brackets |
Ohms law may be used to calculate the loads applied by components during the design of a circuit:
For example ;
A vehicle is fitted with a work lamp, which is fitted with a 12volt 55watt bulb. The current drawn by the lamp can be
calculated using Ohms law by :
Current (I) = Power in watts (W) divided by Voltage(V).
Current (I) = 55 / 12 = 4.58amps
From this the cable size , fuse, and switch capacity required can be calculated.
Changing the rating of the bulb to 100 watts would have the following effect:
Current (I) = 100/12 = 8.33 amps current draw .
The resistance of the lamp can be calculated by
Resistance(R)=Voltage (V) divided by Current (I)
For the 100watt lamp this would be 1.44 Ohms.
If the original cable installed was only capable of handling a 5 amp current flow this would now need to be replaced to
take into account the extra consumer load.
To fit additional worklamps on a vehicle without replacing original cabling , Worklamps utilising LED technology could
be used with power consumption as low as 7 watts.
To determine the correct size of replacement cable use cable manufacturers specific data for their product and the current loading.The tables below are approximate guide only.Cable placement, length, and duty cycle of the circuit should also be taken into account when specifying cable.
Various designations exist for vehicle wiring and termination:
BS AU7a
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British Standard AU7a is for colour coding of wiring used on older british vehicles.
|
DIN 72 552
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DIN terminal numbers are used for defining identifying connection to various devices
|
DIN 47 002 |
DIN colour codes for electrical wiring |
12N
|
Trailer wiring plug and socket for 12 volt rear lighting circuits to ISO 1724
|
12S
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Trailer wiring plug and socket for 12 volt supplementary system wiring eg Reverse lamps, power supply, fridge etc. to ISO
3732
|
13S
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13 pin plug and socket wiring for including lighting and auxilliary circuits ISO 11446
|
24N
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24 volt commercial vehicle trailer wiring plug and socket for lighting and trailer braking control ISO 1185
|
24S |
24 volt Supplementary S type plug and socket for reverse lamps, rear fog lamps , and supplementary circuits. ISO 3731 |
ISO 7638 |
24 volt Antilock braking system plug and socket. |
ISO 12098 |
Commercial vehicle plug and socket wiring for trailer lighting , Auxilliary circuits, axle lift, traction control, CANbus |
Typical cable rating for single core pvc auto cable to BS6862
Cable size
|
Typical current rating
|
9/0.3mm 0.65mm
|
5.75 Amps
|
14/0.3mm 1.0mm
|
8.75 Amps
|
28/0.3mm 2mm
|
17.5 Amps
|
35/0.3mm 2.5mm
|
21.75 Amps
|
44/0.3mm 3.00mm
|
27.5 Amps
|
65/0.3mm 4.50mm
|
35 Amps
|
84/0.3mm 6.0mm
|
42 Amps
|
97/0.3mm 7.0mm
|
50 Amps
|
84/0.4mm 10.00mm
|
70 Amps
|
266/0.3mm 20.0mm |
135 Amp Starter cable |
37/0.90mm 25.0mm |
170 Amps Starter cable |
61/0.9mm 40.0mm |
300 Amps Starter cable |
61/1.13mm 60.0mm |
415 Amps Starter cable |