Silly Question - Interior Lights

[Planty]

hey there wise ones......
daft question i know, but......the interior llight bulb in the roof bit went a few weeks back and i changed it, wot came out was an 8 watt, wot went back was a 10 watt (blue of course)..... now then the bulb in the door light has 'gone' it's only a 3 watt, i tried in a little local shop today and the smallest they can get is a 10 watt..

is this safe... will it melt the plastic cover..??
can anyone suggest where i should try next, was gonna try halfrauds tomorra, any ideas......???

see ya'll
Planty

[Scuddy]

Try your nearest Motor Factors in yellow pages..usually all sizes available

If you keep uprating the wattage of the bulbs all over the place you'll start blowing the fuses as too many amps are being drawn by them.

(1 watt = 1 amp x 1volt, do the maths - too many watts and the amps goes up to compensate as voltage is set at 12v). Pop goes the fuse as it goes past its amp rating.

Scuddy

[NiftyNev]

hey there wise ones......
daft question i know, but......the interior llight bulb in the roof bit went a few weeks back and i changed it, wot came out was an 8 watt, wot went back was a 10 watt (blue of course)..... now then the bulb in the door light has 'gone' it's only a 3 watt, i tried in a little local shop today and the smallest they can get is a 10 watt..

is this safe... will it melt the plastic cover..??
can anyone suggest where i should try next, was gonna try halfrauds tomorra, any ideas......???

see ya'll
Planty

More watts = More heat.This is ok for short periods but will melt plastic if left on too long.

Neville

[Leodis]

(1 watt = 1 amp x 1volt, do the maths - too many watts and the amps goes up to compensate as voltage is set at 12v). Pop goes the fuse as it goes past its amp rating.

Scuddy

If thats the case how come a 1000 watt vacuum cleaner doesn't blow a 13 amp fuse? or am I missing something here.

[Rixtar]

Yes slightly. the equation goes
P (power in watts)= V(Volts) x I (amps)

=> I = P/V

So vacum Cleaner at 1000watts running on 240V draws a current I in amps of

1000/240 = 4.1667 amps


Therefore putting a 13 amp fuse in your vacuum doesnae really protect it, as the power at 240 volts needed to blow a 13 amp fuse = 240x13 = 3120Watts.

It has alwayse seemed strange why electrical suppliers usually fit 13 amp fuses to even the smallest of gadgets such as clock radios. the gadget will blow up long before the fuse. Perhaps it is a conspiracy to get us to buy new gadgets. My vidoe carced it recently and the repairman said it would have been saved the damage if it had the correct fuse.