Ship's Power (or portable GPS) Question

I'm an old technology guy, flying comfortably behind my Lowrance 100, but
I've encountered a problem where there shouldn't be one: The internal
batteries still die and take the unit down, even when running on "ship's
power".

Last fall, I added a power outlet in the cockpit to power the Lowrance (as
well as provide an always hot point where I can hook a battery tender during
winter months).

The strange thing is that even using ship's power, the unit still dies from
time to time "wanting" new batteries. Makes no sense to me, since the 4
AA's in it should last a long time given that they shouldn't see any drain..
Besides, shouldn't the unit function just fine on ship's power even if the
internal batteries are dead or nearly so?

By the way, having the always hot circuit for the battery tender is very
handy...

Thoughts on what the GPS/power problem might be?

KB

On Mon, 28 May 2007 14:59:40 -0400, Kyle Boatright wrote:

I'm an old technology guy, flying comfortably behind my Lowrance 100, but
I've encountered a problem where there shouldn't be one: The internal
batteries still die and take the unit down, even when running on "ship's
power".

Last fall, I added a power outlet in the cockpit to power the Lowrance (as
well as provide an always hot point where I can hook a battery tender during
winter months).

The strange thing is that even using ship's power, the unit still dies from
time to time "wanting" new batteries. Makes no sense to me, since the 4
AA's in it should last a long time given that they shouldn't see any drain..
Besides, shouldn't the unit function just fine on ship's power even if the
internal batteries are dead or nearly so?

By the way, having the always hot circuit for the battery tender is very
handy...

Thoughts on what the GPS/power problem might be?

KB


I'm not familiar with your particular unit, but some units external power
only charges the batteries and doesn't run the unit directly. So If your
running non-nicads in it (akaline) then they will not be charged but just
run down like normal. An akalines life can be extended a little by
"charging" them but not drastically so.
John

On Mon, 28 May 2007 14:59:40 -0400, Kyle Boatright wrote:

Thoughts on what the GPS/power problem might be?

Most give an indication when power switches from external to battery,
newer Lowrance models even read out external voltage. Do you see this
indication when plugging and unplugging external power? Make sure your
outlet is still putting out power like you assume. A buddy of mine has
one (Lowrance 100), but doesn't have the adapter so I couldn't verify
this...

I have a Magellan GPS that will kill any batteries (2xAA) left in it, in
a matter of days. One possible reason is that the internal lithium
battery has failed and its trying to maintain memory and other things.
However if it has external power, it won't run the internal batteries
down. I just never use it anywhere where it has always on power,
everything gets turned off with the master switch. I simply pull the
batteries out everytime I'm finished with it for the day. Drawback is
that you have to initialize it everytime you want to use it...

I have a fear that our Lowrance 2000C could cause the batteries to leak
in it, so they come out everytime it won't be used for more than a
couple of days...

"Kyle Boatright" wrote

The strange thing is that even using ship's power, the unit still dies
from time to time "wanting" new batteries. Makes no sense to me, since
the 4 AA's in it should last a long time given that they shouldn't see any
drain.. Besides, shouldn't the unit function just fine on ship's power
even if the internal batteries are dead or nearly so?

Thoughts on what the GPS/power problem might be?

The most obvious point to start at, is checking the ship's power to GPS
cord/adapter.

Check to see if the cord is putting out any power, and if it is, you still
will need to make up a jumper cord so you have a place you can check the
output voltage while the adapter is under load.

It could be that it is not putting out enough voltage/amps while it is under
load.

If that checks out, check the path from where the cord plugs in to, to where
the power joins the circuit board for continuity.

Is there possibly a switch to set the unit to change over from internal to
external power? That is just a long shot guess.
--
Jim in NC

"Morgans" wrote

It could be that it is not putting out enough voltage/amps while it is
under load.

To further expound on that point, you need to know what the power draw is
demanded by the unit. Take a thin piece of cardboard, and put a wire on one
side to contact the positive battery contact, and run it to an amp/ohm/volt
meter, then back to the contact of the GPS unit, to be able to read the amps
(or milliamps) actually drawn from the batteries.

Of course, the output of the ships power adapter must be equal to or greater
than the draw of the GPS. I really think you will find your problem, there.
--
Jim in NC

"Morgans" wrote in message
...

"Morgans" wrote

It could be that it is not putting out enough voltage/amps while it is
under load.

To further expound on that point, you need to know what the power draw is
demanded by the unit. Take a thin piece of cardboard, and put a wire on
one side to contact the positive battery contact, and run it to an
amp/ohm/volt meter, then back to the contact of the GPS unit, to be able
to read the amps (or milliamps) actually drawn from the batteries.

Of course, the output of the ships power adapter must be equal to or
greater than the draw of the GPS. I really think you will find your
problem, there.
--
Jim in NC

Interestingly, someone sent me a private e-mail indicating that he had the
same problem with his Lowrance Airmap 100. He resolved the problem by
trading up to a newer unit. ;-)

Reading through the Airmap's manual, it is supposed to switch to the ship's
power if the voltage from the ship exceeds the voltage of the 4 AA's, which
is roughly 6 or 6.5V. There shouldn't be a problem with the power from the
airplane. Its voltage is ~14, and the circuit is fused for 10A and wired
for 15-20A. I've checked the voltage it on several occasions.

My guess is that there is a problem with the internal switch on the Airmap,
and that I can't solve it on my end.

I guess I'll just have to keep feeding the thing AA's.

KB

"Kyle Boatright" wrote in message . ..

"Morgans" wrote in message ...

"Morgans" wrote

It could be that it is not putting out enough voltage/amps while it is under load.

To further expound on that point, you need to know what the power draw is demanded by the unit. Take a thin piece of
cardboard, and put a wire on one side to contact the positive battery contact, and run it to an amp/ohm/volt meter,
then back to the contact of the GPS unit, to be able to read the amps (or milliamps) actually drawn from the
batteries.

Of course, the output of the ships power adapter must be equal to or greater than the draw of the GPS. I really
think you will find your problem, there.
--
Jim in NC

Interestingly, someone sent me a private e-mail indicating that he had the same problem with his Lowrance Airmap 100.
He resolved the problem by trading up to a newer unit. ;-)

Reading through the Airmap's manual, it is supposed to switch to the ship's power if the voltage from the ship exceeds
the voltage of the 4 AA's, which is roughly 6 or 6.5V. There shouldn't be a problem with the power from the airplane.
Its voltage is ~14, and the circuit is fused for 10A and wired for 15-20A. I've checked the voltage it on several
occasions.

My guess is that there is a problem with the internal switch on the Airmap, and that I can't solve it on my end.

I guess I'll just have to keep feeding the thing AA's.

KB



My power cord for the Lowrance 2000c has a little green LED in the part that plugs in to the cigarette lighter plug it
that lights up when it is powered up...

"Blueskies" wrote

My power cord for the Lowrance 2000c has a little green LED in the part
that plugs in to the cigarette lighter plug it that lights up when it is
powered up...

I know understand that the GPS is made to accept ships power without the
power being altered, first. I agree that it is a problem deep in the unit.

I would just change the plug to go directly to the batteries, at a voltage
the batteries could accept without being over charged, and let the batteries
run the unit while being continuously charged and kept full by a regulated
power source, like a cell phone or something uses.

There are all kinds of universal 12 volt to whatever volt power supplies at
wally world. They would probably supply the right voltage, and enough
milliamps.
--
Jim in NC

"Kyle Boatright" wrote

I guess I'll just have to keep feeding the thing AA's.

If you wanted to keep the thing running, you could use a voltage regulator
to feed the batteries directly at a few tenths of a volt over 1.25 volts per
cell, which would keep the batteries charged, and the voltage regulator
taking the brunt of supplying the juice for the unit.
--
Jim in NC

"Kyle Boatright" wrote:

Interestingly, someone sent me a private e-mail indicating that he had
the same problem with his Lowrance Airmap 100. He resolved the
problem by trading up to a newer unit. ;-)

Reading through the Airmap's manual, it is supposed to switch to the
ship's power if the voltage from the ship exceeds the voltage of the 4
AA's, which is roughly 6 or 6.5V. There shouldn't be a problem with
the power from the airplane. Its voltage is ~14, and the circuit is
fused for 10A and wired for 15-20A. I've checked the voltage it on
several occasions.

My guess is that there is a problem with the internal switch on the
Airmap, and that I can't solve it on my end.

I guess I'll just have to keep feeding the thing AA's.

Check to see if there is a fuse internal to the plug power adapter. It
might be open...