The Cables-to-Go USB panel mount is sold out. Here's a cheaper one, although it sounds as if you may need to supply your own screws.

JimG wrote: BT-RoR, ET, ET-RoR,

shouldn't we call it ET-RoC(Rate of Change) since at times it can be slightly in the negative.

My TC4C/HTC arrived today and I don't quite understand everything. I found this "manual" http://www.mlgp-llc.com/htri/index.html, HT Roaster Interface Technical Reference Manual pending Randy's Manual.

Randy's original post has a Cables-to-Go USB panel mount and Rama has an alternative. Why isn't a standard USB cable sufficient? I don't see how the panel mount goes into my laptop unless I have it bass ackwards and then I don't see how it connects.

There are 2 8-pin connections on the HTC board, marked CTL and PWR. I assume from the photo that the connector from the control panel of the HT is now plugged into the PWR connector, the purchased connector from HT goes on the CTR and the other end goes below to the main board on the bottom of the back compartment of the HT.

I earlier posted about Kapton® Insulated Thermocouple Wire type K 30 gauge. This is not a good idea if bought as just wire as it is real hard to get the insulation off and sepate the 2 wires. Bob McBob's find of the ready made insulation kit is the way to go.

I'm confused about the ground. I have the P version and will connect to a lap top. Do I need to ground anything, there are ground terminals TCGRD and a resistance ground?

Alot of my questions were answered by rereading the "Installing ET and BT probes in a Hottop" thread. There is a plethora of material on HB which have been rendered superfluous by this new technology. When I'm done ripping my HT apart for its semiannual maintenance, I'll have more questions.

Marvin

The purpose of the panel mount USB cable adapter is simply to make the installation look prettier and eliminate any requirement for strain relief. It's basically just a short internal USB extension from the board with a male connector and screw holes. You can connect a USB cable directly to the board and drill a hole for it in the roaster, but it won't look as pretty, and you run the danger of snagging it and damaging the board.

The manual is almost complete and may be available as soon as Monday or Tuesday.

I originally cut a USB cable in two, fed it through the hole in the bottom of the machine, and spliced it back together inside (soldered and heat shrink). Once I established that all was working (I was testing what was a pre-production "Guinea Pig Special" to some extent) I opted for the panel mount version so that there would not be another dangling cord. it also allows the back to be removed and teh cable unplugged from the TC4C without the USB "permanently" attached through the chassis. Handy for maintenance as well.

You are correct- the CTRL connector connects to the control panel, and the PWR connector attaches to the "Main Board" (Power Board).

Hi, Marvin -

I apologize for the (temporary) lack of a good users guide. As Randy said in his post, a dramatically improved version should be ready this week. I am also happy to answer questions via email or here.

iginfect wrote:Randy's original post has a Cables-to-Go USB panel mount and Rama has an alternative. Why isn't a standard USB cable sufficient? I don't see how the panel mount goes into my laptop unless I have it bass ackwards and then I don't see how it connects.

This has been addressed by others. The panel mount is optional and just makes for a little cleaner install.

iginfect wrote:There are 2 8-pin connections on the HTC board, marked CTL and PWR. I assume from the photo that the connector from the control panel of the HT is now plugged into the PWR connector, the purchased connector from HT goes on the CTR and the other end goes below to the main board on the bottom of the back compartment of the HT.

Reiterating information in Randy's post, connect the CTL header to the Hottop control panel. Connect the PWR header to the power (or main) board that lies below the drum motor.

iginfect wrote:I earlier posted about Kapton® Insulated Thermocouple Wire type K 30 gauge. This is not a good idea if bought as just wire as it is real hard to get the insulation off and sepate the 2 wires. Bob McBob's find of the ready made insulation kit is the way to go.

A thermal stripper works pretty well, but this very fine wire is still difficult to work with. If you want, mail me the wire and I'll take a shot at building you some bare bead probes. I have a homespun thermocouple welder that can put a decent bead on the ends of the wires.

iginfect wrote:I'm confused about the ground. I have the P version and will connect to a lap top. Do I need to ground anything, there are ground terminals TCGRD and a resistance ground?

The TCGND pins are there as a fallback to solve ground loop problems. If you electrically isolate your thermocouples from the roaster as recommended, it is unlikely you will need this. When used, these pins tie the negative side of the TC4C's power supply to the roaster frame through a 10K resistor that is already soldered onto the HTC board. Suggest doing nothing with TCGND until/unless ground loop problems show up.

Jim

JimG wrote:

I have a homespun thermocouple welder that can put a decent bead on the ends of the wires.

another_jim wrote: DIY thermocouple

...30 gauge capton K...Use a fine gauge wire stripper and just twist the sensing ends together -- this will work fine if you are looking for 1C accuracy.

My understanding is that a bead isn't necessary.

Marvin

iginfect wrote:My understanding is that a bead isn't necessary.

Yes, I know that's Jim's position, backed up by his successful experience. But a welded bead is preferable when it is available. I am splitting hairs here, but oxidation can occur between the contacts of the twisted wires, and to some degree oxidation degrades the junction.

If you send them to me for thermal stripping of the insulation, they will come back with beads. Otherwise, the world will continue to turn just fine if you twist 'em.

Jim

First, I'd like to thank Jim and Randy for their time in putting this project together.
Second, I know I may be a pain, but I'm an early user of this system and others may come up w/ same problems. I went to Lowes and Radio Shack this a.m. to get some hardware to attach the TC4C/HTC to the roaster. The nylon bolt that goes through the TC4C board to be attached to another threaded cylinder in Randy's initial picture has threading too small to match anything in the store. In order to order anything online, I would need to know the specs of the threading. Thanks.

Marvin

M3.

Jim

EDIT:

iginfect wrote:First, I'd like to thank Jim and Randy for their time in putting this project together.

Appreciated, but don't leave out Tom!

Jim