Using a power inverter in an Oddessey?

[Martin Fraser]

Hi,
I used a power inverter in my 2002 Oddessey - a Vector brand, 400 Watt - and
had no problem with it for a year or so. Then a couple months ago my
accessory plugs (cigarette lighters) went out, along with my radio.
I checked the fuse (took a while to figure WHICH fuse box it was ! ) and
thought it was OK. When I took it in to the dealer for the 30K service I
asked them to fix it and when I picked it up they said the tech just changed
the fuse and it was fine - but that I had an AC inverter plugged in and I
shouldn't - that was the problem.

Question: Does anyone have any related experience? is there a type of
inverter or AC power supply that WILL work?
I use it for plugging in a laptop (usually for the kids watching DVD's on
long trips) and occasionally for plugging in Phone adaptors (Only because I
run out of Acc outlets with the GPS and the power inverter plugged in to the
two of them)

Thanks for any feedback or suggestions

Martin

 

[Maggot]

Hi,
I used a power inverter in my 2002 Oddessey - a Vector brand, 400 Watt -
and had no problem with it for a year or so. Then a couple months ago my
accessory plugs (cigarette lighters) went out, along with my radio.
I checked the fuse (took a while to figure WHICH fuse box it was ! ) and
thought it was OK. When I took it in to the dealer for the 30K service I
asked them to fix it and when I picked it up they said the tech just
changed the fuse and it was fine - but that I had an AC inverter plugged
in and I shouldn't - that was the problem.

Question: Does anyone have any related experience? is there a type of
inverter or AC power supply that WILL work?
I use it for plugging in a laptop (usually for the kids watching DVD's
on long trips) and occasionally for plugging in Phone adaptors (Only
because I run out of Acc outlets with the GPS and the power inverter
plugged in to the two of them)

Thanks for any feedback or suggestions

Martin

Isn't there a low amp rating on the accessory plugs, like 10 amps? I don't
know what the inverter draws (400 WTS is over 30 amps at 12.6 VDC if 100%
efficient and at full load). My guess this is where the "problem" is.
Probably shoud connect the inverter directly to the battery.

Mike

 

[Martin Fraser]

Isn't there a low amp rating on the accessory plugs, like 10 amps? I don't
know what the inverter draws (400 WTS is over 30 amps at 12.6 VDC if 100%
efficient and at full load). My guess this is where the "problem" is.
Probably shoud connect the inverter directly to the battery.

Mike

Thanks, I'll check on that. It's just a bit odd that it worked for a year or
so before quitting. perhaps a current draw spike from an aging laptop
battery?

I appreciate the suggestion
Martin

 

[Woody]

The accessories sockets are fused with a 15 amp fuse 9 in the passenger
under dash fuse panel. The accessory power socket relay is controlled by a
7.5a fuse 8. The 15 amp also feeds the audio unit, A/t gear position
indicator, dvd unit and rear controller. While the idle current on the unit
may not be enough to blow the fuse surge current can. As the other post said
a 400 watt inverter is way too much for that circuit. You were lucky that it
worked that long. The idle current may have been high enough to melt the
connections in the fuse over time. Also the only to check a fuse is with a
meter or replace it. Looking at it doesn't always work. Look for a 100 or
150 watt inverter to use. They are cheap. I got one for about
$30............

 

[Martin Fraser]

OK, Thanks!
I don't think that a 150 W unit will run a laptop playing a DVD - do you?
If the Laptop will run on 150 W (i.e. it's only drawing 1.25 amps) then
whether I have a 150 or a 400 W unit wouldn't matter, right?

Is it the case that the Laptop will trip the fuse in the 150W unit where it
would have blown the Honda #9 fuse if the 400 W unit was used?

Thanks VERY much for your most helpful response

Martin

 

[Maggot]

OK, Thanks!
I don't think that a 150 W unit will run a laptop playing a DVD - do you?
If the Laptop will run on 150 W (i.e. it's only drawing 1.25 amps) then
whether I have a 150 or a 400 W unit wouldn't matter, right?

Is it the case that the Laptop will trip the fuse in the 150W unit where it
would have blown the Honda #9 fuse if the 400 W unit was used?

Thanks VERY much for your most helpful response

Martin

No it won't. You miss the point. The car voltage is 12.6 volts. To
generate 150 wts of power at 120 VAC you will need in excess of 150 wts at
12.6 volts DC or 11 amps. Fogetting efficiencies, this will give you 120 vts
AC at 1.25 amps. So a 150 Wt laptop will work but with all the losses
involved with the inverter I suspect you will be approaching 15 amps, which
may be the fused limit on the accesory plug.

I still suggest you connect the inverter directly to the battery.

 

[Maggot]

No it won't. You miss the point. The car voltage is 12.6 volts. To
generate 150 wts of power at 120 VAC you will need in excess of 150 wts
at 12.6 volts DC or 11 amps. Fogetting efficiencies, this will give you
120 vts AC at 1.25 amps. So a 150 Wt laptop will work but with all the
losses involved with the inverter I suspect you will be approaching 15
amps, which may be the fused limit on the accesory plug.

I still suggest you connect the inverter directly to the battery.

I think what I am trying to say here is that although there may be a 15 amp
fuse on the line, Honda recommends (at least for the 2004 Odyssey that I
have) that "These sockets are intended to supply power for 12 volt DC
accessories that are rated at 120 Wts or less (10 amps)." So if the
combined power of the laptop and the power losses inherent in the inverter
exceed 10 amps then you may heat up the fuse and ultimately blow it.

My Compaq EVO 610c uses about 90 WTS max or about 7 amps at 12.6 volts DC.
I've never measured it but this is its rated power consumption. Can you
get a direct DC to DC converter for your laptop? Seems to me that this may
be a more efficient and less problematic way of powering the unit.

If not, I still think the best thing then would be to hook the inverter
directly to the car's battery, and it's not that difficult to do. Just be
sure you fuse it for its rated power maximum (in the case of the 400 wt
inverter I'd use a 25-30 amp fuse).

Mike

 

[Martin Fraser]

No it won't. You miss the point. The car voltage is 12.6 volts.

Dooh! - sorry. If I reread my post I'd have picked up my stupidity (I like
to think)
I'm always thinking in a 120 V world...

Yes, my inverter is fused, (and it did come with battery connectors - but
they're aligator clips) I will look at the battery wiring and find a likely
spot to tap in to the + side.

Not to sound too obtuse (ok I already do) - what would you use to wire it?
Household plastic sheathed 14g 3 strand ok?

and where would you pass through the fierwall? the steering collumn?

I realy appreciate your patience!

Martin

 

[Randolph]

Yes, my inverter is fused, (and it did come with battery connectors - but

they're aligator clips) I will look at the battery wiring and find a likely
spot to tap in to the + side.

Most Hondas have an under-hood fuse box. On mine there is one fat wire
coming in to that fuse box from the battery and one from the alternator.
These both have screw terminals, and are good points to hook up
high-power accessories. Crimp a ring terminal to your wire use one of
the screw terminals. For the ground lead, follow the ground wire from
the battery to where it is connected to the chassis. Again crimp a ring
terminal to your wire and use the same grounding point as the battery
uses.

Not to sound too obtuse (ok I already do) - what would you use to wire it?
Household plastic sheathed 14g 3 strand ok?

14 AWG is skimpy. At 150W and an efficiency of 80% (fairly typical
value) you will be drawing about 15A average current. The peak current
will be quite a bit higher than 15A, so to limit your resistive losses I
would go no smaller than 10 AWG. Get individual 10 AWG wires from your
favorite auto parts store, black for negative, yellow for positive. (The
inverter should be in the cabin, not under the hood). Remember to put an
in-line fuse in the positive wire within a few inches of were you tap
into battery voltage.

and where would you pass through the fierwall? the steering collumn?

Have a close look at the firewall. You will probably find some unused
rubber plugs you can pull out and thread the wires through the hole. Use
a grommet for your wires.

 

[Maggot]

Dooh! - sorry. If I reread my post I'd have picked up my stupidity (I like
to think)
I'm always thinking in a 120 V world...

Yes, my inverter is fused, (and it did come with battery connectors - but
they're aligator clips) I will look at the battery wiring and find a likely
spot to tap in to the + side.

Not to sound too obtuse (ok I already do) - what would you use to wire it?
Household plastic sheathed 14g 3 strand ok?

and where would you pass through the fierwall? the steering collumn?

I realy appreciate your patience!

Martin

Now there's a challenge ;-)

I'll be honest and tell you I've never done it in my Odyssey (only have had
it for 2 months and it's too cold here to want to spend any time trying to
wire something). I have owned several vehicles that I have run wiring (I'm
an amateur radio operator and had to run some heavy duty cables to the
passenger compartment and the trunk from the engine compartment).

First of all I'd use 14 or 12 gauge stranded wire, not solid. Stranded wire
will not break over time as quickly as solid wire from the normal vibrations
in the car. Secondly you will want to place an in-line fuse somewhere in the
engine compartment before the wire passes through the firewall. As to
connecting it directly to the battery, I have done exactly that (to the
positive connector or if you are lucky you may find a free tab in the fuse
block located in the engine compartment.

Auto parts stores will carry pre-assembled wiring complete with an in-line
fuse. You only need to run the positive line to the passenger compartment,
the negative return can be made to the car body itself. I'd be really
carefull passing the wire through the firewall. You may find other wiring
passing through a rubber grommet and will be able to pass yours along side,
sometimes an icepick can be used to puncture the rubber to allow a reasonably
watertight passage. Be careful you don't break or pierce the existing
wiring. Or, you may find a place to drill a small hole in the firewall.
Again be careful and assure that you aren't going to puncture some important
structure. You should place a rubber grommet in the hole to minimize
chaffing of the new wire, then seal it with silicone cement.

I think I'd start by looking for a complete cigarette lighter recepticle
assembly at the auto shop. This will come with all the necessary wires, fuse
and perhaps directions that will help. The recepticle can be mounted
somewhere in the vehicle and you could then use your existing setup.

HTH,

Mike

 

[Martin Fraser]

Randolph, Mike -
I really appreciate your help. The fact that you both agreed, chapter and
verse without referencing each others post is Very reassuring.

You and this group are a great resource, I only wish that I might be able to
return the flavor some day.

Sincerely,
Martin