OP
srands
This needs explaining from both 12 Volt DC and 240 AC Volt perspective:
12 Volt dc, we're NOT concerned about the cost of electric, because a car alternator generates this for free (Well apart from fuel & wear & tear of car & driver!) as is a by product of engine running (One cog turns, a belt to the alternator, another cog turns, electric produced, power lead to battery, charging battery). Hence the only real preoccupation here is what is the AMPAGE of the PART (If unknown use MultiMeter to determine, see 1st msg in this post)? Once this is known, then specifying the correct THICKNESS LEAD/CABLE and FUSE is one of the only fitment considerations
Calcs (W = Watts, V = Voltage, A = Amps):
1000 W's = 1 KW (In other words W * 1000 = KW)
A x V = W (Eg 0.8A * 12v = 10Ws)
W / V = A (Eg 10Ws / 12v = 0.8A)
Ah x 10 = A (EN) (Eg 56 Ah * 10 = 560 A [EN])
| DC 12 Volt Cable Guide | ||
| Individual insulated wire thickness in mm with approx max | AMPs | WATTs |
| 2.7mm | 3A | 36w |
| 3.0mm | 10A | 120w |
| 3.8mm | 20A | 240w |
| 5.0mm | 35A | 420w |
| 6.2mm | 50A | 600w |
| 1.2CM | AWG8 / 40A | 480w |
| 1.6CM | AWG4 / 70A | 840w |
Note: To power an AC 240 Volt appliance in a car, you need an INVERTER (I'd recommend a very generous maximum margin to power your SMALL appliance, such as I have fitted 1000W Inverter for a 100W LAPTOP!). WHY? Because your laptop voltage is different to your car battery, for example: Car batteries = 12V. My Laptop power = 20V with psu (Power Supply Unit AC to DC). And bigger is always better, as may use USB powered extras (Hard drive, cameras, etc), or may get larger spec laptop.
240 Volt ac, we ARE concerned about the cost of electric, because ELEC is charged by the KW.
Small Appliances are stated in WATTs (This figure is the approx figure IF an appliance is used for AN HOUR, even though the reading on ENERGY MONITORS is instantly displayed. For example a kettle may only be used for 3 mins, and it's max maybe 2200 Watt's, however it's consumption is NOT 2200 Watt's unless it is used continuously for an hour!).
Large Appliances over 1000 Watt's are stated in KiloWatts such as KETTLES, DISH WASHERS, WASHING MACHINES, etc.
ELECTRIC used in houses/businesses is measured with an ELECTRIC METER, and in KWs.
Once again specifying the correct THICKNESS LEAD/CABLE and FUSE is an important fitment consideration. Since appliances already come with a LEAD, the same thickness or bigger is adequate. The FUSE must be greater then the Ampage max of the appliance and the cable lead must be thicker Ampage then the fuse Ampage.
However if fitting new SOCKET RING/RADIAL circuit need to be fitted, consideration has to be given the total max in amps of all applainces using that circuit, hence use appropriate socket wire cable, sockets/fixtures, etc.
| AC 240V (Appliance Wire) Cable Guide | ||
| Individual insulated wire thickness in mm with approx max | AMPs | WATTs |
| 0.2mm | 1A | 240w |
| 0.5mm | 3A | 720w |
| 0.75mmm | 6A | 1440w |
| 1.00mm | 10A | 2400w |
| 1.25mm | 13A | 3120w |
| 1.5mm | 15A | 3600w |
| 2.5mm | 20A | 4500w |
| 4.00mm | 30A | 7200w |
| AC 240 Volts (Socket/W) Cable Guide | ||
| Individual insulated skt wire thickness in mm with approx max | AMPs | WATTs |
| 1mm | 15A | 3600w |
| 1.5mm | 20A | 4800w |
| 2.5mm | 27A | 6480w |
| 4mm | 36A | 8640w |
| 6mm | 46A | 11040w |
| 10mm | 63A | 15120w |
| 16mm | 85A | 20400w |
Want a FUSEBOX CIRCUIT and MCB/RCD calculator? See my spreadsheet MCB/RCD CALC See the 3rd tab (If MCB's are different ampages) or 4rd tab (If MCB's are same ampage)
Calcs (W = Watts, V = Voltage, A = Amps):
1000 W's = 1 KW (In other words W * 1000 = KW)
A x V = W (Eg 5A * 240v = 1200Ws)
W / V = A (Eg 1200Ws / 240v = 5A)
Note: To power a DC 12 Volt appliance in a house, you need either an adequate:
~ AC to DC plug: Maplin stores, Mobile phone stores, or stalls in retail shopping centres)
or
~ AC to DC psu (power supply unit): Maplin stores
or
~ CAR BATTERY
Still need more ELEC/utility calculators? See my very comprehensive workbook spreadsheet (See 1st tab, scroll down) ELEC GAS WATER autocalc: 1st tab, scroll down
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