Run TV on an inverter?
We just bought a class C motorhome. It has a TV but it’s 120V and requires the generator to run all the time your watching the set. We have an inverter that’s 200 watts. I’m thinking of trying to run...
Forum Discussion
wa8yxm wrote:
One thing to consider is how much power it sucks. With batteries we talk about amp horus and the USABLE power can be as low as 25% of the battery's C/20 rating (IE 25 amp horus for most Group 27/29 size) or as high as 50% for True Deep cycle (like over 100 amp hours for a pair of GC-2 Or nearly 100% for LiFePo4.
If the TV draws 100watts that's about 1 amp at 120 volt and about 10 at 12 volt. so 100 amp hours of battery would run it about 2 horus.
Once you start talking inverters, best to use watt-hours. Amp-hours is a short cut when everything from power source to consumption is running 12v.
Watt-hours = Amp-hours * voltage (there are some technicalities but close enough for our purposes)
So if the battery bank is 100 amp-hours, you have around 1200watt-hours but lead acid batteries shouldn't be taken below 50%, so you have about 600watt-hours.
If the TV draws 50watts, figure around 60watts with losses due to the inverter. That means you have about 10hours (600w-hr/60w = 10hr) of TV time before you should stop using the battery.
Caveats:
- Look up your actual battery, TV and inverter and use those numbers.
- This assumes you start with a fully charged battery. If you start at 80%, you only have 30% available to use.
- Is your house battery bank isolated from the starting battery (if a MH). You don't want to wake up in the morning and not be able to start the motor.
