Disconnect battery when plug into the house power?

Jltab

Dear everyone,
Does anybody done this before? 
Also when T@B is connected to house power, does the battery charge as well?
I have 2106 T@B max S

Normfun

Nope. The only time I disconnect my battery is when it's inn storage for a couple of weeks. That keeps the battery from draining. The rest of the time a trickle charge from the converter or my solar is kept on the battery. 

ChanW

Jltab, you can remove the battery when connected to house power, and yes the house power charges the battery.

irvingj

Here's a related question:

My understanding is that when hooked up to shore power, the 120V doesn't actually go to the 120V outlets and appliances, but rather goes to the inverter, which:
1) charges battery
2) supplies 12VDC to 12V circuits (lights, etc)
3) supplies 120VAC to outlets and appliances

Is this correct, or is there also a direct connection to 120VAC circuits?

Just curious!

Nomad

irvingj - Shorepower goes to the "converter" to handle the 12v stuff (your 1,2,3) but also passes thru and powers the 120v outlets.
Note: A converter takes 120 and converts it to 12 - An inverter takes 12 and produces 120. The T@B has a built in converter.

Michigan_Mike

Agree with what PX said above....  The converter charges the battery up, supplies 12 volts to the 12 volt components in the trailer and allows 120V to "pass through" via the breakers in the converter.  

I think the converter question is a good one as many new trailer owners who buy the Little Guy and T@B units are confused by the above, really not knowing or understanding what the electric converters do.  This is a frequently asked question on the forums as many assume that the converter powers up the 120V outlets when they are boondocking and are confused when they have no 120V power in remote locations and are not plugged into shore power.  

Another way of looking at these items (converter/inverter) are that they are actually small electric transformers which they are....

Converter - steps down voltage from 120V AC to 12V DC and charges the on-board 12V DC battery 

Inverter    - steps up voltage from 12v DC to 120V AC

ChanW

That converter box actually has three roles.

• It converts the 120v to 12v to power the 12v items, as well as 'intelligently' charging the battery.
• It acts as a 'breaker box' for the 120v shore power supply, providing the120v circuits
• It acts as a fuse panel for the 12v items whether powered by the battery or the converter

I'd be nice if it also incorporated the 'inverter' function, giving us 120v from the battery, but alas...

Nomad

ChanW - Built-In Inverter - But can you imagine people trying to do battery/power management. Plug in some high-draw AC appliances and boom, dead battery.

ChanW

Yeah, and it would have to be switched, to prevent phantom draw when not in use.

Too complicated. I like the Tab simple...

ScottG

If in doubt about how something works, I follow the trail of evidence (which, in this case, are the cables snaking around under the seat behing the panel). A little exploration reveals that a cable direct from the external plug serves the main AC breaker, and that four downstream breakers are connected to cables running directly to the GFCI wall receptacles, and dedicated receptacles for the Alde, air conditioner, and fridge.

In short, it's wired just like the 120V AC circuits in your house. As previous posters noted, there's no inverter, so these circuits will only work when plugged into shore power.

irvingj said:

Here's a related question:

My understanding is that when hooked up to shore power, the 120V doesn't actually go to the 120V outlets and appliances, but rather goes to the inverter, which:
1) charges battery
2) supplies 12VDC to 12V circuits (lights, etc)
3) supplies 120VAC to outlets and appliances

Is this correct, or is there also a direct connection to 120VAC circuits?

Just curious!

Michigan_Mike

And the bottom line/underlying intent here is that most people just want "these things" to be able to "make their coffee tasty & hot" every morning and the occasional need to heat up the trailer and keep things cozy and fire up the TV/DVD, etc......  

ChanW

And there's always one little 120v item that you gotta have, that can't be got in 12v...

irvingj

OK, got it, thanks for the clarification. Having recently bought a Roadtrek Sprinter-based RV, there were/are some things to get used to. Now I got it- the T@B has a converter, the Roadtrek an INverter. Wasn't sure if the T@B had a similar set-up, but now I see the difference.

Thanks again!

I will offer my T@B for sale again in the spring, but I still like visiting this forum, and will most likely continue to do so. Hope that's OK. Nice place, good learning opportunities. (Still really like our little T@B, however!)

ChanW

To come back to the OP thread subject, it's a good question whether you can have the battery out of the Tab while connected to shore power. Most car battery chargers should not be powered up until they're already connected to the battery, so I was surprised to hear that using shore power without the battery installed was ok'd by the manufacturer. 

WFCO designed this function into the converter. Nice feature.

Michigan_Mike

I normally don't work on anything without first turning the power off first and testing for any voltage present on the system.  I know there are exceptions, but I'd definitely unplug from shore power before working on the battery just to be on the safe side.  

ChanW

Heh! I guess that was worded unclearly! 

Have edited it to say the battery need not be in the Tab when/if the Tab is powered by shore power.. B-)