I would like to do some testing on our Refrig unit.

Minimum would be to monitor icebox temperature and voltage to compressor so
that I can see on-off cycle and resulting temperature vs time for a 1-2 day
period.

If possible, I would like to add current to compressor and temperature in
area where compressor/condenser is located.

Since this is just a fact finding test, I would like to keep the cost down.

I have seen individual USB temperature and voltage loggers at Lascar
Electronics. For example:

http://makeashorterlink.com/?V2BD2567D and

http://makeashorterlink.com/?P5CD2567D

Does anyone know of a Canadian or US source and especially for a unit that
might accept several inputs?

Someone suggested earlier on rec.boats.cruising that I just use a video
camera, but I need to do this over 24-48 hrs to determine why my refrig
controller at times seems to go into hibernation!

Any ideas welcomed.

GBM

Price is right but I don't like the set 30 minute sample rate, the range or
the 4F accuracy. I (and I think Richard Kollmann) use the Onset Hobo
dataloggers. For $200 including software it has RH, temperature and 2
external inputs. More expensive but you would have about the same amount in
the Lascar units if you want to monitor the same things and a heck of a lot
more flexible. You can monitor interior and exterior temps, humidity and
with about $10 of parts cobble together a hall effect current sensor to
monitor to amps used. Those are the 4 factors you need to monitor
refrigerator efficiency. You can set the sample period anywhere from .5
seconds to several hours,accuracy is about +-1F, or 4 times better and the
battery lasts up to 5 or 6 months.

Support is really good too. Their tech actually designed the current sensor
for me and pointed me to where to get the parts.

--
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

"GBM" wrote in message
...
I would like to do some testing on our Refrig unit.

Minimum would be to monitor icebox temperature and voltage to compressor
so
that I can see on-off cycle and resulting temperature vs time for a 1-2
day
period.

If possible, I would like to add current to compressor and temperature in
area where compressor/condenser is located.

Since this is just a fact finding test, I would like to keep the cost
down.

I have seen individual USB temperature and voltage loggers at Lascar
Electronics. For example:

http://makeashorterlink.com/?V2BD2567D and

http://makeashorterlink.com/?P5CD2567D

Does anyone know of a Canadian or US source and especially for a unit that
might accept several inputs?

Someone suggested earlier on rec.boats.cruising that I just use a video
camera, but I need to do this over 24-48 hrs to determine why my refrig
controller at times seems to go into hibernation!

Any ideas welcomed.

GBM

In article , "GBM" wrote:
I would like to do some testing on our Refrig unit.

Minimum would be to monitor icebox temperature and voltage to compressor so
that I can see on-off cycle and resulting temperature vs time for a 1-2 day
period.

If possible, I would like to add current to compressor and temperature in
area where compressor/condenser is located.

Since this is just a fact finding test, I would like to keep the cost down.

I have seen individual USB temperature and voltage loggers at Lascar
Electronics. For example:

http://makeashorterlink.com/?V2BD2567D and

http://makeashorterlink.com/?P5CD2567D

Does anyone know of a Canadian or US source and especially for a unit that
might accept several inputs?

Someone suggested earlier on rec.boats.cruising that I just use a video
camera, but I need to do this over 24-48 hrs to determine why my refrig
controller at times seems to go into hibernation!

Any ideas welcomed.

GBM



I have been looking at loggers from these companies.....

http://www.microdaq.com/measurement_computing/index.php

http://www.omega.com/vh/hometm.html

In article , (GregS) wrote:
In article , "GBM"
wrote:
I would like to do some testing on our Refrig unit.

Minimum would be to monitor icebox temperature and voltage to compressor so
that I can see on-off cycle and resulting temperature vs time for a 1-2 day
period.

If possible, I would like to add current to compressor and temperature in
area where compressor/condenser is located.

Since this is just a fact finding test, I would like to keep the cost down.

I have seen individual USB temperature and voltage loggers at Lascar
Electronics. For example:

http://makeashorterlink.com/?V2BD2567D and

http://makeashorterlink.com/?P5CD2567D

Does anyone know of a Canadian or US source and especially for a unit that
might accept several inputs?

Someone suggested earlier on rec.boats.cruising that I just use a video
camera, but I need to do this over 24-48 hrs to determine why my refrig
controller at times seems to go into hibernation!

Any ideas welcomed.

GBM



I have been looking at loggers from these companies.....

http://www.microdaq.com/measurement_computing/index.php

http://www.omega.com/vh/hometm.html

"http://www.measurementcomputing.com/cbicatalog/directory.
asp?dept_id=559&top_id=557&dept_name=temperature


http://www.omega.com/ppt/pptsc.asp?r...B-1&Nav=dase01



You should be able to see the temperature change as compressor goes on off
with some delay.

greg

In article , "GBM" wrote:
I would like to do some testing on our Refrig unit.

Minimum would be to monitor icebox temperature and voltage to compressor so
that I can see on-off cycle and resulting temperature vs time for a 1-2 day
period.

If possible, I would like to add current to compressor and temperature in
area where compressor/condenser is located.

Since this is just a fact finding test, I would like to keep the cost down.

I have seen individual USB temperature and voltage loggers at Lascar
Electronics. For example:

http://makeashorterlink.com/?V2BD2567D and

http://makeashorterlink.com/?P5CD2567D

Does anyone know of a Canadian or US source and especially for a unit that
might accept several inputs?

Someone suggested earlier on rec.boats.cruising that I just use a video
camera, but I need to do this over 24-48 hrs to determine why my refrig
controller at times seems to go into hibernation!

of course defrost always screws things up, especially if it is failing.
I specifically wanted to log the temperature as it defrosts in my use.
Its bad that manufactures do not offer the refridgerature owner having
the option to set the defrost, time of day, instead of the way they do it.
You do not want defrost during usage hours.

greg

In article , (GregS) wrote:
In article , "GBM"
wrote:
I would like to do some testing on our Refrig unit.

Minimum would be to monitor icebox temperature and voltage to compressor so
that I can see on-off cycle and resulting temperature vs time for a 1-2 day
period.

If possible, I would like to add current to compressor and temperature in
area where compressor/condenser is located.

Since this is just a fact finding test, I would like to keep the cost down.

I have seen individual USB temperature and voltage loggers at Lascar
Electronics. For example:

http://makeashorterlink.com/?V2BD2567D and

http://makeashorterlink.com/?P5CD2567D

Does anyone know of a Canadian or US source and especially for a unit that
might accept several inputs?

Someone suggested earlier on rec.boats.cruising that I just use a video
camera, but I need to do this over 24-48 hrs to determine why my refrig
controller at times seems to go into hibernation!

of course defrost always screws things up, especially if it is failing.
I specifically wanted to log the temperature as it defrosts in my use.
Its bad that manufactures do not offer the refridgerature owner having
the option to set the defrost, time of day, instead of the way they do it.
You do not want defrost during usage hours.

I cannot find the orginal logger I was interested in. I think it was only $40.
I thought it was from Omega. It had the advantage of specifying delay
time of sensor, and had the option of exposing the sensor for minimum delay time.

greg

Dallas Semiconductor sells temperature loggers as part of their iButton
line which can be placed wherever you want records. They come in a can
about the size of a quarter. You can also purchase a USB interface,
which you can connect the temperature logger into to get the data out
of it, and set the parameters to sample the data in the first place.
See http://para.maxim-ic.com/cache/en/results/4872.html for the USB
interface, and http://para.maxim-ic.com/cache/en/results/4871.html for
the loggers themselves.

Starter kits are available from
http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2820; this kit for $60
includes the USB interface, and a thermocron (which might be for the
wrong temperature range). The thermocrons typically have a 10 year
lifetime.

I've strapped these to water heater output lines and watched the usage
patterns of hot water. Software for windows XP is free for download.
If you're trying to use this with Linux, try the "One Wire File System"
software.

Thanks - I checked out their site - A bit technical, but it seems that the
iButton line is aimed at temperature/humidity logging. I would also need to
know when compressor switches on and off - For this, I would ideally use
current measurement (0-10A DC), voltage (0-30V) or even something like
sound. Two temperatures would be better than one.

Because of this, the buttons made for monitoring transportation
temp/humidity, may not be the best choice. The multi port dataloggers would
be great, but cost is a bit high for a one time experiment. There are units
that interface with a computer that are aimed at school science projects
that are more reasonable, but my laptops CDROM just failed!

http://www.drdaq.com/

I would prefer a stand alone unit for data collection that I can connect to
my desktop computer for downloading. The Onset Hobo would do the job, but by
time software and sensors are added, it becomes a bit pricey for a 1 time
job.

GBM

wrote in message
ps.com...
Dallas Semiconductor sells temperature loggers as part of their iButton
line which can be placed wherever you want records. They come in a can
about the size of a quarter. You can also purchase a USB interface,
which you can connect the temperature logger into to get the data out
of it, and set the parameters to sample the data in the first place.
See http://para.maxim-ic.com/cache/en/results/4872.html for the USB
interface, and http://para.maxim-ic.com/cache/en/results/4871.html for
the loggers themselves.

Starter kits are available from
http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2820; this kit for $60
includes the USB interface, and a thermocron (which might be for the
wrong temperature range). The thermocrons typically have a 10 year
lifetime.

I've strapped these to water heater output lines and watched the usage
patterns of hot water. Software for windows XP is free for download.
If you're trying to use this with Linux, try the "One Wire File System"
software.

simpler is to take a couple of turns of the positive feed to the
compressor round a reed switch. Pump on, reed closes, pump off reed
opens. A lot simpler than having to read the current.

Ian M

Some of the dataloggers have the possibility of monitoring an event such as
a switch on/off, but not all.

I think I have finally come up with a simple method - I will just use two
independent temperature loggers. One in the ice-box and one just above the
condenser fan. The latter will get an upward spike in temperature when the
compressor comes on. This way, I should be able to plot box temperature vs
compressor on/off cycle. This should do it.

Thanks for the input.

GBM

"nimbusgb" wrote in message
oups.com...
simpler is to take a couple of turns of the positive feed to the
compressor round a reed switch. Pump on, reed closes, pump off reed
opens. A lot simpler than having to read the current.

Ian M