Onset's response to my questions on icebath & broken nubs (see below) 

Dear Jim,

Paul has forwarded your email to me. In regards to your questions:

1. You want the ice to be a small consistent size. You can place ice in a
plastic bag and break the ice up with a hard object, such as a hammer. If
you do not want to crush the ice yourself, you may find a grocery store
that is willing to sell you some of the crushed ice that they pack their
produce in. You want the ice and water to create a slurry.

The crushed ice bath is listed as a means for customers to test their
loggers accuracy when they do not have access to a controlled environment.
You will see differences if you use chunks of ice in water, the
thermistors that are closer to the ice chunks will read differently then
the thermistors that are floating in water. To maintain a consistent
temperature, it is important that you follow the ice bath directions very

If you would like, we can test the loggers for accuracy. There are two
types of services available for testing the loggers:

A.Check up Service - Cost is $35.70 per logger. With this test you will
not receive a written report, we only check to see if the loggers are
working within the specifications that is outlined in the TidBits Manual.

B. NIST Certification - Cost is dependent upon how many temperature points
you would like the TidBits tested at. There is a set up charge per unit of
$25.00. In addition to this, there is a charge per temperature point that
each individual TidBit is tested at. Point charges are $15.00 per standard
point or $20.00 per custom point. Standard temperature points are every
10° C from -30° C to + 120°C. Custom temperature points are in 1°C
increments. Test points selected must be within the range that the logger
can read.

For example, if you sent in 1 TidBit that you wanted tested at 20 and 35
degrees C, the cost would be:

1 Set up charge - $25.00
1 Standard point - $15.00
1 Custom point -    $20.00

Total cost            $60.00

If you were to send in 20 units for the example above it would be
$1,200.00. You would receive a certificate per unit             showing what the
logger read and the NIST bath read at each point. If you would like to
send in the TidBits for either procedure, please contact us for a RMA
number in advance.

2. There have been many verbal discussions between Onset sales
representatives and researchers associated with ME Lobster Conservancy,
UMASS Dartmouth, Gulf of ME Lobster Foundation and Atlantic Offshore
Lobsterman's Assoc, regarding ways that the TidBits may be protected to
keep them intact. In addition, we have suggested moving into a sturdier
product such as the HOBO Water Temp, it was stated that these were too
large. We can offer suggestions, however we are unable to test these
methods in the environment that these groups are using them within. The
TidBits were not designed to be in an environment where they would be
dragged and banged around. This type of environment will cause the
communication LED nubs to break.

The nubs are breaking off due to physical damage, not a design defect.
Onset's warranty is for manufacturing defects, we cannot be liable for
environmental damages that occur in the field. To avoid further problems
the TidBits will need to be placed in a protective casings so they are not
banging into other objects. Since the TidBits have been introduced, we
have sold well over 70,000 units. If there were a design defect, it would
be evident through a high return ratio for this problem. From 11/20/02 -
1/2/04 we have sold 13,941standard TidBits, during this time span 59 units
were returned that had broken nubs, this is less then 0.5%. Out of the 150
custom units that the Gulf of ME Lobster Foundation purchased, only one
was returned under RMA #104309.

We have recently released a Stainless Steel Temperature logger that
communicates via USB, perhaps this is better suited to your application.
Following is a link to the page on our website that lists the
specifications for this product:


If you would like to discuss your application and the use of another
product, or methods of protecting the TidBits,  please contact Eileen
Sandherr at (800) 564-4377 ext 154. hope this information is helpful to
you. If I can be of further assistance, please feel free to contact me.
Thank you.

With kind regards,

Linda Cain
Customer Service Manager

>Hi again Paul-
>Can you direct this email to whoever you think might best answer these
>1) I noticed your web site:
>suggest using "crushed ice".  Just how crushed should this be?  What
>should I expect if I use regular ice cubes? Where do you get your supply
>crushed ice when you preform this type of calibration check at your
>facility.  I would be willing to drive from North Falmouth to whever that
>source it located so that I get get a supply.  I expect to be collecting a
>large set of probes on Friday Jan 30th and want to do this test on them.
>By the way, would ONSET be willing to conduct this calibration test? If
>what would be the charge for, say, a set of 20 probes.
>2) We continue to lose valuable probes and data due to TidBit nibs
>off.  We have lost dozens of probes due to this unexpected fault in the
>design.  Shouldn't we get some sort of compensation for this lost?  We did
>not expect nearly 20-30% of our probes to have this problem.  Paul Borsari
>has been helpful in retrieving most of the data for us and can attest to
>numbers of probes we have lost.

For further information contact: James.Manning@noaa.gov

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