[MOTOXHauler]

Hi

Building my van with a tv/ps3 for kids, my van came with a standard alternator (Not heavy duty) and im installing a 600 watt inverter for PS3 and TV. Any suggestions on

Adding a 2nd battery?
Adding a charging / volt meter?
If a 2nd battery is suggested then should i do series or parallel?

TV was about 35 watt and PS3 Slim was about 255 watts

I am hard wiring the sine inverter to the battery with 4 guage wire. Also thinking of connecting a LED rope light so i dont accidentally leave the inverter on (rope light led will remind me, hopefully! )

 

[morey]

Will the TV/PS3 need to work when the engine isn't running? For how long?

 

[MOTOXHauler]

thanks morey, van will be running most of time cause this is mostly for driving, but the tv can be adjusted so it can be viewed out the sliding door area as we are parked , so if i didnt have to keep it running while parked that would be ideal. as for how long would it be used with the engine off? an hour or two i guess.

 

[alarmist]

parallel. Easiest thing would be to order the factory bits from a dual AGM setup.

 

[morey]

Hi
TV was about 35 watt and PS3 Slim was about 255 watts

Your PS3 power usage seems high, probably more like 140 watts.

You should calculate your daily power requirements (when engine is not running) before deciding what to do. Let's say you want to run the PS3/TV for 4 hours per day.

TV
35 watts * 4 hours = 140 Wh

PS3
140 watts * 4 hours = 560 Wh

Total
140 + 560 = 700 Wh per day

Amp Hour Calculation
700 Wh / 12 volts = ~60 amp-hours per day

If you only have the single battery it is only 70 amp-hours. Easy to see that you can't rely on just the stock single battery, but you probably already knew that.

Now that you know you need a second battery you have options. You could buy the parts from Ford to upgrade to the 2 battery option (140 amp-hours) or you could buy a third party battery (Lifelines are popular) and wire it in parallel using a charging relay.

I suggest you put these calculations in a spreadsheet and play with the numbers before proceeding.

 

[jonsobi]

Keep in mind that even though the stock battery is 70 AH, only 50% of that is usable without damaging the battery's lifespan.

 

[orton]

If you are watching the TV from outside the van I will assume the sun is shining. A house battery charged by a solar panel would seem to be a good choice. No danger of running down the vehicle battery whole watching Howdy-Doody. (shows my age).

Since you only have a single battery would suggest a separate house battery.

 

[morey]

And if adding a second battery or electronics DIY stuff is not for you take a look at one of these off the shelf solutions http://www.goalzero.com/power-packs . It will cost you more but will save you a lot of time.

 

[ksauers]

Your PS3 power usage seems high, probably more like 140 watts.

You should calculate your daily power requirements (when engine is not running) before deciding what to do. Let's say you want to run the PS3/TV for 4 hours per day.

TV
35 watts * 4 hours = 140 Wh

PS3
140 watts * 4 hours = 560 Wh

Total
140 + 560 = 700 Wh per day

Amp Hour Calculation
700 Wh / 12 volts = ~60 amp-hours per day

If you only have the single battery it is only 70 amp-hours. Easy to see that you can't rely on just the stock single battery, but you probably already knew that.

Now that you know you need a second battery you have options. You could buy the parts from Ford to upgrade to the 2 battery option (140 amp-hours) or you could buy a third party battery (Lifelines are popular) and wire it in parallel using a charging relay.

I suggest you put these calculations in a spreadsheet and play with the numbers before proceeding.

What charging relay do you need?
I don't know what to get. I want to add a battery this winter.
I alsodon't know how to wire them.

 

[morey]

What charging relay do you need?
I don't know what to get. I want to add a battery this winter.
I alsodon't know how to wire them.

The charging relay you need depends on your requirements (current, engine battery protection, etc...). Here is a popular one http://assets.bluesea.com/files/resources/instructions/990180180.pdf .

Not something that can be answered simply. I suggest you look at what others are doing. Search this forum and http://sprinter-source.com/forum/ for "electrical diagram" and read. Once you have read everything, start again and read some more.

If you don't have the time or interest in putting a decent amount of work researching I would suggest going with a proven and supported solution http://www.goalzero.com/power-packs .

 

[tthrsn]

Keep in mind that even though the stock battery is 70 AH, only 50% of that is usable without damaging the battery's lifespan.

I was working on this issue the other day. The cost of discharging Lifeline AGMs beyond 50% is not as great as you might think. Here's some data about the expected life of a battery when routinely discharged a given amount:

20% discharge = 3000 20% cycles = 600 "complete" cycles
50% discharge = 1040 50% cycles = 520 "complete" cycles
80% discharge = _550 80% cycles = 440 "complete" cycles

I have attached a graph of all the possibilities. (I notice that I forgot to label the axes: the horizontal axis is depth of discharge in percent and the vertical axis is number of cycles.) The data for the first graph was taken from the last page of the Lifeline Technical Manual.

It's the "complete" cycles that that show you how much life or value that you are getting from your battery, not the partial cycles. The graph shows that there is nothing special about discharging to 50% (though it does show that to minimize costs, discharge to only 20%).

Accordingly, I will not worry about heavily discharging my house batteries. But I will never treat my starter batteries that way because they are abused enough by the high starting currents and the poor charging regimen that they suffer.

 

[jonsobi]

An occasional discharge greater than 50% should not be fatal. I try to avoid dropping below 12.4v if possible.

 

[MOTOXHauler]

did a 6 hour drive this weekend, worked awesome!!! kids played PS3 and watched a movie...i need to clean up some small details and will post some pics soon. FYI...they still asked how much longer..lol..

 

[airmengarrettm]

did a 6 hour drive this weekend, worked awesome!!! kids played PS3 and watched a movie...i need to clean up some small details and will post some pics soon. FYI...they still asked how much longer..lol..

I'm calling you out MOTOXHauler!!!
You may have a life outside of this forum but but but you promised pics of your set-up with the TV and PS3!
hahahaha

 

[MOTOXHauler]

ok, u got me! i swear every week i do one more improvement but everyone has be so helpful with their advice so i made this prelim video on how i set up my moto van, constructive criticism welcome

https://youtu.be/WCkbZrph5Js

PS eventually i will take it down and make a better one And post it on my other u tube channel