"Richard J Kinch" wrote in message
. ..

Adding insulation is not typically an improvement in anything of recent
construction. That's a fantasy factoid lingering from the 1970s energy
crisis, endlessly repeated by people who've never measured the realized
benefit.

Richard - Unfortunately our boat is not of recent construction. The original
icebox had just 1/2" of polyurethane insulation. When I installed the refrig
unit, I added as much as I could on the outside. But, it is still not as
much as is often recommended. Only way of adding more, is on the inside.
But, if it won't make much difference in compressor run time, I would prefer
not to do this because of cost of so-called "space-age" insulation or space
taken by conventional insulation.

Perhaps this explains why I would like to measure present power usage, then
add temporary sheets of foam using 2-way tape and measure again.

Thanks for all the input so far guys!

GBM

"Keith" wrote in message
oups.com...
If it's 110V, just plug it into one of these:
http://www.thinkgeek.com/gadgets/electronic/7657/
They used to have these at Radio Shack, but they quit carrying them.
For $30, they're really worth it.


The boat refrig (Waeco Coolmatic) is at present DC only, but I can
apparently get a converter called a Mobitronic MPS-35 that would allow me to
automatically switch to A/C at dock. This might be a useful addition anyway,
and with that the Kill a Watt would probably do what I am looking for as
well as check the quality of the A/C. may be worth a try?

GBM

"Glenn Ashmore" wrote in message
news:tbH7g.22412$iF3.13428@dukeread01...
Here is an idea that will cost about $150 and do a lot more than measure
the
amps.

A Hobo 12-012 data logger with internal temp and RH sensors and 2 external
sensors.

http://www.onsetcomp.com/Products/Pr...a_loggers.html
Plug a temperature sensor in one of the external inputs and an Ampsense
Hall
effect current sensor on the other. http://www.ampsense.com/

With the free basic Hobo software you can capture the data and load it
into
a spreadsheet. That will give you the external temp and RH, internal box
temp and amp draw on a common timeline.


Having the temperature difference would be a useful piece of additional
information. But, I will have to think of some other uses for this device
before parting with $150.00 for my test

GBM

----- Original Message -----
From: "Dennis Pogson"

Connect it to an isolated, fully-charged cheap auto battery of known
capacity, and see how long it takes to discharge the battery. I assume
that
is what you want the data for in the first place. Not very accurate, but
hellish useful!


I do have a few 12v batteries ( I recently installed 6v,s) - using one of
them and monitoring the voltage could provide a rough measure of usage. If
the battery is (was?) say 100 Ah and the unit draws 50Ah/ day, I suppose I
would get a reasonable voltage drop if I let it run for say 12 hours
overnight?

GBM

Adding insulation is not typically an improvement in anything of recent
construction. That's a fantasy factoid lingering from the 1970s energy
crisis, endlessly repeated by people who've never measured the realized
benefit.

Richard - Unfortunately our boat is not of recent construction. The
original
icebox had just 1/2" of polyurethane insulation. When I installed the
refrig
unit, I added as much as I could on the outside. But, it is still not
as
much as is often recommended. Only way of adding more, is on the
inside.
But, if it won't make much difference in compressor run time, I would
prefer
not to do this because of cost of so-called "space-age" insulation or
space
taken by conventional insulation.

Perhaps this explains why I would like to measure present power usage,
then
add temporary sheets of foam using 2-way tape and measure again.

Thanks for all the input so far guys!

GBM

This topic (now moving away from recording to efficiency) has had a
great deal of exposure.

As one who has taken a sawzall to his original box (anyone wanna buy a
very cheap, perfectly good, 110/engine drive, dual split-system cold
plate[s - 2], quite large system?), without getting technical about it,
BTU are BTU. However many it takes is what it will require for the
cooling system.

An advantage to the older engine drives (techumseh compressors like
used to be on 60s era Ford products) is that they can make a ton of ice
in an hour, properly set up, so there's ample capacity if you have the
right cooling plates, regardless of how poorly insulated your box might
be.

However, if it's not adequately insulated, it will sweat - and
eventually rot stuff, usually behind the fascia, where you don't see
it. That's why, in our boat, the galley sole was skinned before I
bought it, and why the area under the reefer, inaccessible until we
tore it out, was mostly gone. Ample pix of that removal in the late
04/early 05 galleries if you wanted to see what happens.

So, back to the story. You can either live with it, add mechanical
(could be attached to a genset or the main engine - or rigged with a
110 motor and pulley, if you're dockside most of the time) cooling, or
(unless you don't mind losing the space occupied by the original
housing/insulation, in which case you could build it from the inside)
rebuild it from scratch, as we did.

At that point, your options expand but as you've identified, it's a
tradeoff between foam for cheap but fat, or vacuum for dear but thin.

I vehemently (well, not to be angry, just strong) disagree with the
"70's hype" bit. If you don't keep the heat out, you have to remove
it. There's a point of diminishing return, but my marker is to take an
infrared thermo (cheap at the cheapo tool places, and even sometimes at
the Shack) and point it at the face of the insulated, cold, box. Then
point it at another similar face nearby which isn't near the
reefer/freezer. If they're within a couple of degrees of each other,
that's probably as good as you'll get. The less techie test is to use
your hand. If the reefer feels notably cooler, you probably don't have
enough insulation. However, if you have a face plate trim which isn't
in contact with the box (another barrier, good idea) then it masks the
truth. If you have a top loader, your countertop is a good place for
the test, even though the least amount of BTU go through the top (heat
rises, so the convection component is very small there).

As to your "temporary" sheets of foam, part of the equation is
preventing air movements. You have to be very aggressive about sealing
joints and overlapping as many times as possible (longer path for air),
along with as precise a fit as you can manage. Again with my pictures
for examples - I used paper patterns for exact fits, and at that
spoiled some of my sheets, doing them over.

FWIW, my original thought was to add insulation to the inside of the
box, too, replacing the countertop as I went. Without the gory details,
that proved impossible. Had I known the reality which might have
avoided all the gory details, I might still have cut it out, because
the original insulation, even if it's not sweated (as yours nearly
certainly must have, as thin as it is), loses most of its R-value over
the years. Technology today helps, and epoxy encapsulation retards it,
but you'll still lose some R over the years with new stuff, space age
or extruded Poly-x. However, 30 years from now, I'll not care about it
in my boat :{))

I have a lead on what used to be a very much less expensive (than
Rparts or Glacier Bay, the usual suspects) source for vacuum panels if
you decide to go that route.

Hope that helped and not just repeated what you already know...

L8R

Skip

Morgan 461 #2
SV Flying Pig KI4MPC
http://tinyurl.com/p7rb4 - NOTE:new URL! The vessel as Tehamana, as we
bought her

"Believe me, my young friend, there is *nothing*-absolutely
nothing-half so
much worth doing as simply messing, messing-about-in-boats; messing
about in
boats-or *with* boats.
In or out of 'em, it doesn't matter. Nothing seems really to matter,
that's
the charm of it.
Whether you get away, or whether you don't; whether you arrive at your
destination or whether you reach somewhere else, or whether you never
get
anywhere at all, you're always busy, and you never do anything in
particular; and when you've done it there's always something else to
do, and
you can do it if you like, but you'd much better not."

"Skip Gundlach" wrote


So, back to the story. You can either live with it, add mechanical
(could be attached to a genset or the main engine - or rigged with a
110 motor and pulley, if you're dockside most of the time) cooling, or
(unless you don't mind losing the space occupied by the original
housing/insulation, in which case you could build it from the inside)
rebuild it from scratch, as we did.

Skip,

We are done with the initial re-insulation and have the Waeco Coolmatic
installed. So let's not get into other types of compressors or changing the
external box insulation - that is behind us!

I just completed insulating the box - insulation now varies from about 1.25"
to 3" where I used polycyanurate board but is 5+" where I poured in foam
around the back and most of bottom.

If I have excessive compressor run time, I could add internal insulation on
the two areas where I could only fit in an extra 3/4" of foam. It would be
quite easy to temporarily add sheets of cyanurate with two-sided tape for a
test.

There's a point of diminishing return, but my marker is to take an
infrared thermo

Not a bad idea - I will try the hand feel first!

Had I known the reality which might have
avoided all the gory details, I might still have cut it out, because
the original insulation, even if it's not sweated (as yours nearly
certainly must have, as thin as it is), loses most of its R-value over
the years.

Our 1/2" insulation was at least totally encapsulated and was bone dry, at
least on the piece I cut out - I have sealed the openings I cut with epoxy
and sealed all edges of the new foam with aluminum tape or epoxy.

Basically now come down to testing and seeing if I need to add the internal
insulation. I am going to insulate the side of the engine room that faces
the icebox. I am also going to ventilate the cupboard that is between the
two.

Thanks guys for all the good ideas. I have several ways I can go and will
try the cheapest first

GBM

In article tbH7g.22412$iF3.13428@dukeread01, Glenn Ashmore
wrote:

Here is an idea that will cost about $150 and do a lot more than measure the
amps.

A Hobo 12-012 data logger with internal temp and RH sensors and 2 external
sensors.

http://www.onsetcomp.com/Products/Pr.../U12_family_da
ta_loggers.html

I'm not real happy with this URL. When I accessed it, I got the
following in my Java Console window:

----------------------------------------
Java Plug-in 1.5.0
Using JRE version 1.5.0_06 Java HotSpot(TM) Client VM
User home directory = /Users/peter


----------------------------------------------------
c: clear console window
f: finalize objects on finalization queue
g: garbage collect
h: display this help message
l: dump classloader list
m: print memory usage
o: trigger logging
p: reload proxy configuration
q: hide console
r: reload policy configuration
s: dump system and deployment properties
t: dump thread list
v: dump thread stack
x: clear classloader cache
0-5: set trace level to n
----------------------------------------------------

init()
GroopzApplet 2.1 build 17 starting...
active icon URL:
http://mygroopzserver.onsetcomp.com:.../1000/groopz-a
ctive.gif
away icon URL:
http://mygroopzserver.onsetcomp.com:.../1000/groopz-a
way.gif
paging icon URL:
http://mygroopzserver.onsetcomp.com:.../1000/groopz-p
aging.gif
Initializing network...
HTTP tunneling disabled.
Attempting TCP connection to port 6789
Network connection established.
sent login from 13153778814316625 to service (siteID 1000)
received login response from service (siteID 1000)
Applet has started.

-----------------------------------------------------------

No warning or request. This is bad behaviour IMO. Can't do any harm to
this computer, but even so, I don't like it.

Why is an applet talking home to mommy?

Just why do they need to d/l an applet and run it to provide what on
the face of it is a pretty simple Web page?

I was interested because we make extensive use of dataloggers. The ones
we use are dataTakers - http://www.datataker.com/. These are NOT cheap,
but we run them in Antarctica and on icebreakers for months at a
stretch unattended. I'd like to find something cheaper, but my
electronics engineers express a total lack of faith in USB devices when
run time extends to months straight. Too many bad experiences.

PDW

Don't understand that. Nothing special about the site. May be a break in
my paste. Try http://www.onsetcomp.com/ and search for the U12 family.

They are fairly inexpensive data loggers but probably overkill unless you
are a compulsive tester/experimenter like me. So far I have only used it to
document tests of ice chests (the $60 Coleman Xtreme beat the heck out of
the $150 Iceytek and equaled the $400 Frigid Rigid) but once I start tuning
Rutu it will come in real handy.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

"Peter Wiley" wrote in message
. ..
In article tbH7g.22412$iF3.13428@dukeread01, Glenn Ashmore
wrote:

Here is an idea that will cost about $150 and do a lot more than measure
the
amps.

A Hobo 12-012 data logger with internal temp and RH sensors and 2
external
sensors.

http://www.onsetcomp.com/Products/Pr.../U12_family_da
ta_loggers.html

I'm not real happy with this URL. When I accessed it, I got the
following in my Java Console window:

----------------------------------------
Java Plug-in 1.5.0
Using JRE version 1.5.0_06 Java HotSpot(TM) Client VM
User home directory = /Users/peter


----------------------------------------------------
c: clear console window
f: finalize objects on finalization queue
g: garbage collect
h: display this help message
l: dump classloader list
m: print memory usage
o: trigger logging
p: reload proxy configuration
q: hide console
r: reload policy configuration
s: dump system and deployment properties
t: dump thread list
v: dump thread stack
x: clear classloader cache
0-5: set trace level to n
----------------------------------------------------

init()
GroopzApplet 2.1 build 17 starting...
active icon URL:
http://mygroopzserver.onsetcomp.com:.../1000/groopz-a
ctive.gif
away icon URL:
http://mygroopzserver.onsetcomp.com:.../1000/groopz-a
way.gif
paging icon URL:
http://mygroopzserver.onsetcomp.com:.../1000/groopz-p
aging.gif
Initializing network...
HTTP tunneling disabled.
Attempting TCP connection to port 6789
Network connection established.
sent login from 13153778814316625 to service (siteID 1000)
received login response from service (siteID 1000)
Applet has started.

-----------------------------------------------------------

No warning or request. This is bad behaviour IMO. Can't do any harm to
this computer, but even so, I don't like it.

Why is an applet talking home to mommy?

Just why do they need to d/l an applet and run it to provide what on
the face of it is a pretty simple Web page?

I was interested because we make extensive use of dataloggers. The ones
we use are dataTakers - http://www.datataker.com/. These are NOT cheap,
but we run them in Antarctica and on icebreakers for months at a
stretch unattended. I'd like to find something cheaper, but my
electronics engineers express a total lack of faith in USB devices when
run time extends to months straight. Too many bad experiences.

PDW

On Mon, 8 May 2006 21:06:43 -0400, "Glenn Ashmore"
wrote:

They are fairly inexpensive data loggers but probably overkill unless you
are a compulsive tester/experimenter like me.

Heh --- compulsive. I use one of their devices (dedicated
temp and humidity) to monitor a wine cellar, recording
conditions every few minutes. They make a shuttle that
lets you collect data from the logger and carry it to
the PC for downloading. That way you don't have to dismount
the logger and take it to the computer for downloading.

I wired 2 DC powered run-hour meters into the circuitry which opens the
solenoid valves for my refrigerator and freezer. Only 1 valve is open at
once. If you don't have this, look for something similar in your system
(thermostat, on/off switch, etc.) About once a week I enter the run-hours
into a spread sheet and look for anomalies. It's highly consistent, so if
something is out of wack, I know it right away.

As mentioned, the amperage is not constant, but if you watch your gauges
you'll see that the amperage quickly becomes constant (in my case once the
expansion valves have closed down.) Doing a you can come up with an average
amperage per minute.

My system consists of a Glacier Bay 1/2 HP 12V DC motor driving a Bitzer IIY
compressor with an 18F plate in the frig and a 0F plate in the freezer. I
have Carel electronic thermostats which allow me to accurately set the on/off
points which measure plate temp. This is important. The unit cycles on
demand. When it starts it draws about 40A and then drops to about 30A after
about 5 minutes. My system draws 85AH per day in the Caribbean where the
temp ranges from 80 to 90F and the water temp is 80F. I'm quite happy.

-- Geoff

"GBM" wrote in news:4Zw7g.72646$fd.56060
@read2.cgocable.net:

What is the best way of measuring the power drawn by a boat's refrigeration
unit?

Is there a way to do this without any expensive instruments?

I was thinking of installing an ammeter in the line to the compressor to
determine the current draw, but manufacturer does not recommend this. Even
with that, I would need an hour meter or some such device to know how often
and for how long the compressor runs.

I would like to test existing installation, then add some "temporary"
insulation to the inside of the box and then test again to see what
improvement I might get if I added permanent insulation.

GBM