Foretravel Owners' Forum

Our new Dell Studio Laptop is trying to teach me something but I don't know what.
In the past I have plugged the AC cord into an outlet, turned on the Inverter and off we went.
This week as we left home the computer gave me a low battery warning and quit.
I then found that the AC Cord was not receiving power from the wall outlet.
Later ( now ), I plugged into an old cheap 300 watt inverter that I had in the bay, now AC cord is powered and all is well.
WHAT THE H... ? These things drive me nuts, What I know about computers and tricity you could put on the Head of a pin.
Even though its working now I have no Idea why. >:D

Gary,

Check the GFCI.  On my coach, the one in the bathroom controls most of the outlets throughout the coach.  I have been caught several times with a dead outlet that I eventually traced to a tripped GFCI.  If that is not the cause, check your circuit breakers.

I use one of the little 3 light testers to verify whether an outlet is working correctly.

Dick

Dick, The GFI was the first thing that I looked at, what puzzles me is why Computer will operate off a cheap plug in inverter but not on the coach inverter.  The cheap inverter is a Little blue box plugged into the cigarette lighter that I found in my bay junk box, it has to be 20 years old.

Is the inverter on? In mine it is not automatically on.

I'd first check that the inverter reports itself as being on, then check the breaker panel for inverter-fed outlets, then check some other outlets to see who if anyone is getting electricity.

By the way, these inexpensive inverters are modified sine wave, so watch for overheating in the power adapter for your computer.  Some switching power supplies don't like MSW. 

Also, these inexpensive inverters can be very critical of 12 volt power.  I've found it necessary to clip them directly to battery terminals to prevent shutdown, as any coach wiring (especially through cigarette lighter sockets) reduces the voltage too much for them to work.

Tom, I checked other outlets to see if inverter was working, and it was.  Little old inverter is plugged in to 12 v outlet in front of copilot ,  power supply to computer does not seem to be overheating.  Mystery remains.

Does anything else work when plugged into that outlet and when running off the coach inverter?  What about plugging the laptop power brick into one of the other inverted outlets?

Not all the outlets in our coach are powered by the inverter.  Our inverter-powered circuits have a small breaker panel at the foot of the bed that does not have a door covering it.  Sometimes they do get bumped into the "off" position by one of the dogs (who also like to turn the block heater on  ::) )

Michelle

how can I determine which outlets are powered via the inverter?

George....  take one of those plug-in meters on the "50 amp tester" and plug it in to all your 110 plugs with the inverter on.  That should tell you which are hot.

George

Regarding modified wave inverters..... we have been using a 400 watt AIMS modified wave inverter to run a laptop for the Silverleaf.  I plug in the laptop charger (old Sony), which draws 1.2amps, so it is probably not using the full 400 watts.  The inverter is plugged into the dash 12 v plug.  We have had some problems with the inverter shutting down when the coach engine is not running, e.g., when we stop for lunch.  That was complicated by the fact that the Sony battery was not very good and provided little in the way of back up.  I replaced the laptop battery and we now make a habit of turning the inverter off and on again when we restart the engine. 

I did some reading last night on true sine wave vs modified sine wave inverters.  One site advised not using anything larger than a 300 watt inverter off of the dash plug.  Evidently, when the engine is turned off and the voltage drops from 14 something to 12 something, the inverter can't cope if it is larger than 300 watts.  Also, I did not see anything in the way of a warning to not use a modified sine wave inverter with laptop battery chargers.  But I will keep an eye on it and make sure it is not getting too hot.

George (the shortstop)

Our solution is less elegant, but quite simple.  I have a multiple outlet strip in back of the driver chair.  We only run chargers for cell phone and 2-way radios off the strip.  So I ran a short AC extension cord to the strip and use this to power my laptop.  Works all the time.

I'm still on first.

Steve, Anything else plugged into the INVERTED outlet works, only the computer brick does not ?? Go figure.. It looks like the small inverter plugged into the cigarette lighter is going to work OK so I have power I'm just mystified as to what is happening.

Does the computer work when plugged into a different inverter-fed outlet or just this one combination computer/outlet has a problem?  If just the one outlet, I'd try an extension cord and see if anything changes.  It might be some physical issue between that particular outlet and that particular plug.

Your coach's schematics in part, plus a simple a/c appliance (like a lamp) and the desire/energy/flexibility to plug and unplug from every outlet in the coach while running only off the inverter.  Including those outlets in the storage bays for completeness.

Michelle

I might be deficient in the "flexibility" department.

Same here. 

I think it's safe to assume most if not all of the accessible outlets on your coach are powered by the inverter.  Obviously, power to the air conditioners and refrigerator (cooling, not ice maker), unless you have an all-electric coach, are only powered by the generator or shore power.

Tom,
 Agree.  I think I will wait and find out as the need arises.  We don't run a lot of stuff when the inverter is on.
 Regards,
 George

Your schematics do contain some of that useful info.  Here's a snapshot of the relevant schematics page for our coach.



See on the right Note 3)  Circuits 1, 2 and 5 are powered by an inverter.  The items shown in the list, with their current draw, are for Circuits 1, 2, and 5

Michelle