Thank you, Jim. This is very helpful.
From: Stable Isotope Geochemistry <[log in to unmask]> on behalf of Jim Palandri <[log in to unmask]>
Sent: Monday, January 25, 2016 12:19 PM
To: [log in to unmask]
Subject: Re: [ISOGEOCHEM] Heating cartridges for gas bench sample block
Here we went through this just last month.
These heating cartridges are of a somewhat specialized type "positive
temperature coefficient," where as explained by our local e-shop
engineer, the current flow is limited as the operating temperature is
We found what appear to be direct replacements here:
but did not receive replies to our requests for a quotation.
Others on isogeochem had indicated they used standard cheapo metal
cartridges as replacements, so we did that too, replacing all three. We
settled upon a non-metric size and the e-shop turned some steel sleeves
on a lathe to enhance contact between the heaters and the heating block.
Some notes we took at the time:
> While the current Jumo PID settings aren't as effective at homing in
on 70C with these
> new heaters, perfect enough. I'm certainly not going to mess with the
> controller. We get from 64 to 70C in twelve minutes which is about one
> quarter the time as before.
> Max overshoot is 70.7C at 15 minutes (from 64C), 69.7 at 24 minutes, and
> getting closer and closer from there. At 70.7 the effect on the
> fractionation factor leads to less than 0.02 per mil shift for d18O,
> which is in my understanding negligible for the Anthropology samples.
Hope this helps?
On 1/25/2016 9:29 AM, Dana Biasatti wrote:
> Hello all,
> Would anyone happen to have the part number for the Thermo heating
> cartridges for the gas bench heating block? Or, if you know the part
> number for the equivalent Watlow part, could you please share? Thank you
> very much!
> Dana Biasatti
> Isotope Specialist
> Center for Environmental Science and Technology
> University of Notre Dame
> Notre Dame, Indiana 46556
Department of Geological Sciences
1272 University of Oregon
Eugene, OR 97403-1272