sunquest
Member
I have a 17" LCD TV mains and 12volt, Freeview box mains and 12volts, DVD player mains only. Which is the best power option when mains is not available? If just an inverter is recommended what wattage? Thanks Geoff
Inverter/ DC2DC. Best solution
- Thread starter sunquest
- Start date
Dave3729
New member
Hi Geoff
I have always found the use of an invertor to be to much of a drain on the batteries. Maybe a small generator would be a better option. When i had mine my batteries would go flat and i had to wait for my solar panel to give enough charge to turn the engines over.
I have always found the use of an invertor to be to much of a drain on the batteries. Maybe a small generator would be a better option. When i had mine my batteries would go flat and i had to wait for my solar panel to give enough charge to turn the engines over.
Dave_Seager
Member
The TV and Freeview box should be run directly from 12v - there is no point in using an inverter for these if they will take 12v.
Therefore you only need an inverter to power your DVD player. These seem to be very low powered. I just checked the specifications of some on the JVC site and they only use 8w.
You should be able to find a ratings plate on yours giving its power requirements. You can then choose an inverter that will provide enough power, plus a bit extra to allow for more current wwhen it starts up.
I use a portable 150w inverter to run various small devices on board without any battery problems so you should be alright. This would appear to be ample for a DVD player, especially since you are unlikely to use it for more than a few hours at a time.
Therefore you only need an inverter to power your DVD player. These seem to be very low powered. I just checked the specifications of some on the JVC site and they only use 8w.
You should be able to find a ratings plate on yours giving its power requirements. You can then choose an inverter that will provide enough power, plus a bit extra to allow for more current wwhen it starts up.
I use a portable 150w inverter to run various small devices on board without any battery problems so you should be alright. This would appear to be ample for a DVD player, especially since you are unlikely to use it for more than a few hours at a time.
Wiggo
New member
Just check the power consumption on the back of the TV. A small inverter should drive it with no problems, but do be careful of your battery consumption. A 300W inverter will draw a steady 25-30A or so from your batteries, so it will knacker an 85Ah battery in not much over an hour or two
AHoy2
Member
Be aware that most 12v DC TVs are very voltage sensitive and may not operate with less than 12v at the set. On most previous installations I have done it has been necessary to operate them via an inverter. Chose a good quality pure sine wave inverter, decent ones will draw minimal current off load and provide high efficiency on load, 300W as suggested.
It is not the inverters that "knacker" the batteries, just that folk don't calculate the load and expect a battery to behave like the national grid :>)
As far as battery capacity is concerned, assume 50% capacity i.e. for a 200AH battery assume 100AH capacity available when charged (real world situation). For easy arithmetic, a combined load of around 120W for TV/F'view/DVD will draw 10A + from your battery so battery discharged after 10 hours (assuming no other load like lights, fridge, water pump etc....). Realistically a couple of 2 hr viewing sessions alongside general domestic load. Small capacity batteries and inverters are not a good combination.
A decent inverter will shut down before the battery voltage falls too far (say 11v) and before the battery is damaged.
RCD protection is advisable on the 230v ac from the inverter.
It is not the inverters that "knacker" the batteries, just that folk don't calculate the load and expect a battery to behave like the national grid :>)
As far as battery capacity is concerned, assume 50% capacity i.e. for a 200AH battery assume 100AH capacity available when charged (real world situation). For easy arithmetic, a combined load of around 120W for TV/F'view/DVD will draw 10A + from your battery so battery discharged after 10 hours (assuming no other load like lights, fridge, water pump etc....). Realistically a couple of 2 hr viewing sessions alongside general domestic load. Small capacity batteries and inverters are not a good combination.
A decent inverter will shut down before the battery voltage falls too far (say 11v) and before the battery is damaged.
RCD protection is advisable on the 230v ac from the inverter.
sunquest
Member
Thanks for all your input guys. I think I will commandeer my sons 150w inverter to run the DVD and use 12volts direct for the TV and Freeview. Geoff