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hottop voltage range


Barrie wrote:


rustic_roaster wrote:


I dont know if it is a matter nomenclature or not but I am pretty sure it is a matter of jumping to conclusions when I read "Early Hottops were more sensitive to voltage " and assumed that meant the heater voltage was now regulated. Wishful thinking on my part.

The company's US website has a table comparing the two current "2K" models. In the row labelled "not sensitive to voltage, no variac needed" both are labelled "Yes." I think Randy G. wrote that?

There is a discussion regarding that statement on Sweet Maria's forum stuck in the middle of a big introduction thread that gives some ideas on how this might be a true statement. The idea is the temp sensor feedback acts to compensate for voltage differences. If you include time into the equation I think the argument gets iffy.


Randy G wrote:

If we look at it logically, it would be difficult to get all the circuitry to raise the voltage going into the Hottop (it would be large and expensive to do so). Since the current models (all "B" and "P" models) allow the user to run the heating element at 100%, any sort of voltage compensation should not be necessary.

If the heater was resized and the default profiles based on using sub full power to the heater when the voltage is at nominal 120V, then that reserve could be used to compensate for lower voltage. It would not for work all voltages but possible a subset of more typical cases. The voltage would only need to be measured and not adjusted.


Randy G wrote:

Me? I currently have two disassembled Hottops on my workbench. Both are receiving the HTC + TC4C installations with my own custom thermocouples- one machine is mine and one for a customer. I will try to take photos along the way. I will have a template for thermocouple location available as soon as I verify its accuracy. But this is a great way to have complete control over the Hottops.

That is great, Randy. I had a frustrating day yesterday, having received my HTC+TC4C in the mail that morning. I had decided that I would not risk the warranty issue with my new HT for two or three months, and for the time being just use the logging feature via your bean chute method. I thought I had identified a machinist in the area who would drill the holes using your templates. To cut a long story short, I went to four machine shops and all declined to tackle it (immediately Grin). I think the problem was the stainless steel plus the smallness of the job. Bodes poorly for the permanent installation. Again, I would have preferred someone else to do the drilling. I don't visualize any major problem with it, other than getting the probes solidly in (the right) place, and I had planned to take the stripped-down and pencil-marked back wall to them for that.
Oh, well. thumbdown I did not know you took customers.
Edited by Barrie on 04/23/2013 10:16 AM
Barrie (San Diego, CA)
"So much to learn, so little time."
Hottop 2K+., Artisan, Jura Capresso ENA 3 (i.e. espresso).
Randy G
I have a punched cover I do not use. Contact me off list and we can work it out.

Attached (I hope) is a photo of the boards which I have mounted and ready to install in the Hottop. I do not normally do this as the time involved makes it quite expensive to do as a "business," liability aside. It necessitates disassembly of the Hottop, another $80 in parts cost in addition to the HTC + TC4C boards, and quite a few hours of labor to do the job right.
Randy G attached the following image:

Life's too short to drink bad coffee.
Hi Guys:

if you are going to continue this TH4 stuff will you please take it over to the TH4 forum; stuff is too hard to find otherwise.

thanks for your consideration in advance,

love ya bunches,


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