Mayday, anyone out there who can help?,

I recently bought a 20” Freeview TV with DVD for my boat.  According to the manual it is a 12V 5amp.  It came with a 240 volt to 12V lead with a standard 3 pin domestic type MK plug, a light-on box (similar to what you see on a laptop lead) and a small cylindrical bulge just before the TV plug.  In my naivety I thought, simply cut off the converter box (to use the plug which goes into the back of the TV) connect these + & - wires to an existing cigar lighter socket on the boat and away you go.  WRONG. 

Firstly the cigar lighter socket is protected by a 240V 2amp fuse.  This blew.

Next, further back up this same circuit there is a switch and, you guessed it, there’s also a fuse on the switch (again 2 amp.) this blew.

I thought, why not connect the lead to the TV direct to my battery avoiding all these small fuses (but I still thought that I should protect it with a fuse).  I did this and used either a 10 or a 15amp car type (can’t remember which and I threw it overboard in disgust).  The TV came on but after a few minutes this fuse blew too.

What is going on?  Can you help?

This link will take you to a description of the product.

http://cgi.ebay.co.uk/20-WIDESCREEN-LCD-TV-FREEVIEW-DVD-PLAYER-24v-240v_W0QQitemZ130245900808QQihZ003QQcategoryZ11071QQtcZphotoQQcmdZViewItemQQ_trksidZp1742.m153.l1262

They also offer a 12V lead with a cigar lighter type bayonet on the end.  Would this have a fuse in it?

The one on the Ebay link states 24v not 12v...

IS the output from the converter definatetly 12 v dc? The cylindrical bulge is probably just a ferrite clamp to reduce/remove any induced RF intereferance.

If it blowing fuses through the amp range I would suggest it points to a short somewhere. I would say return the TV but now you ve cut the lead that might be difficult!

Some cigar light plugs do have fuses in them - usually through a screw top end.

W.

Glyn

The first thing you should do is to check the spec of the television from a plate or sticker - usually on the back or bottom of the set. This should give the current consumption , voltage or wattage.

As a rough guide multiply the ac 240v current by 20 to get the dc current at 12volts or divide the  wattage by 12 to get the 12 volt current consumption. If the set is 120 watts then it will need 10 amps at 12 volts and allowing for switch on surge it may want a bigger fuse or a "slow blow" one. I would try say a 20 amp fuse and see if that holds and ideally measure the current. if that blows i would assume the set may be faulty. 

regards   dave calvert