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tc4c: another parts list
imaroaster
I think the list includes:
For heat control:
ssr
For fan control:
zero cross detecter
random fire ssr

I talked to the folks at Substance instruments and asked about a zero cross detecter and the random fire ssr and they said all I would need is this http://www.auberi...ducts_id=9.I did tell them it was for a motor and he said it should be no problem. What do you all think?

Also my thermal coupler has a spade type plugs how do I connect them to the tc4c?

John
Edited by imaroaster on 08/31/2012 9:00 AM
 
lmclaren

Quote

Switch method zero-cross turn on


The SSR you linked has a zero-crossing detector built in. This means that you can drive it with a dc voltage to turn it off and on and and it will only turn on and off at the zero crossing point. It could be used to replace a relay.

If you want phase dimming then it won't do what you want, so it depends on what you are driving it with. If you are using a off the shelf pid controller then it is probably ok, if you are using something specialized that uses phase control then it may not be a good choice.

btw, if your controller requires a zero crossing input then it is probably a phase dimmer.

Lee
 
imaroaster

Quote

lmclaren wrote:

Quote

Switch method zero-cross turn on


If you want phase dimming then it won't do what you want, so it depends on what you are driving it with.


My goal is to get a tc4c. My understanding is that it would drive (be the controller) for the motor. Right now I control the motor with a 1500 watt dimmer.The motor is a 4" vacuum motor from a Dustbuster, I don't know anything else about it.

-John
 
JimG
The good thing about the TC4C is that it is a general purpose device that can be programmed to do many things. The bad thing about the TC4C is that it is a general purpose device that can be programmed to do many things.

If you wish to have dimmer-type control for your motor, then the TC4C can be programmed to do that. The aArtisanQ firmware is presently available for download. It provides heater control using a standard SSR.

But motor control using the aArtisanQ firmware requires an external zero cross detector (ZCD board) plus a random fire SSR. A standard SSR will not work correctly in a dimmer-style application.

Jim
 
imaroaster
Jim- thanks for nailing that down. Is there a place to get a random fire SSR at a reasonable price? Right now I'm using a mechanical relay would this work (It would be noisy and eventually wear out but would it work)

Now I've been reading and I keep reading about "Slow PWM" but they seem to relate to DC fans, will "slow PWM" work with a standard SSR and an universal motor?

Maybe I should just plan on manually controlling the fan with the dimer switch.

Also how is the TC4C powered? Does it need something like a computer power supply?

Seems like the rabbit hole gets deeper and deeperShock
Edited by imaroaster on 08/31/2012 10:51 PM
 
greencardigan
The TC4C can be powered from the USB connection to the computer or a DC power supply (wall-wart).

I don't think a mechanical relay will work for phase control.

Slow PWM would usually relate to a heater rather than a fan. It could have a period of say one second where 75% power would mean he heater is in for 0.75 seconds then off for 0.25 seconds which wont work well for a motor.

I'm kind of in the same situation as you. I'm planning a new controller using but using the TC4 rather than the TC4C. I hope to use a zero crossing detector and random fire SSR for my blower. I intend to have a control knob (potentiometer) connected to the TC4 to manually adjust the speed but allowing automation of the blower speed someday.
 
greencardigan
If your thermocouple has connectors on it you can find the matching sockets and connect the sockets to the TC4C using some more thermocouple wire. This could be a good idea if you're going to enclose the TC4C in a project box. Otherwise you could just cut the connectors off and connect the ends of the thermocouple wire directly to the TC4C.
 
oldgearhead

Quote

imaroaster wrote:

>snip<
Maybe I should just plan on manually controlling the fan with the dimer switch.

Seems like the rabbit hole gets deeper and deeperShock


The only reason I would automate my vacuum motor would be to
simply turn it down twice during a roast based on time: once at 3 minutes and again at 6 minutes. So far, I've had to problem remembering to do that. However, my DC drive would be easy to automate because it has a 0-10V analog speed control input. Does a TC4 have an analog output available (4-20ma, 0-5vdc, 2-10vdc, 0-10vdc)?
No oil on my beans...
 
JimG

Quote

oldgearhead wrote:However, my DC drive would be easy to automate because it has a 0-10V analog speed control input. Does a TC4 have an analog output available (4-20ma, 0-5vdc, 2-10vdc, 0-10vdc)?


Sort of.

In most applications, IO3 is set up for 5VDC PWM output at 491Hz. Depending on the receiving device, you may or may not need to add a low pass filter to smooth the signal to get a more "pure" 0-5VDC output.

There are also library functions available (see PWM16.h) that make it simple to select from a wide range of PWM frequencies if 491Hz is too slow/fast.

Jim
 
imaroaster
Automation isn't the goal but control is. I'm reworking my roaster and figured this is the time to upgrade my controls. Right now I have no heat control and use a dimmer for the fan. My thought is to use a tc4c to control the heat and figured I could replace the dimmer switch with tc4c control.
 
imaroaster
Found this layout which helps alot. I believe all credit goes to JimG for this. JimG- if there is a problem with me posting this I'll edit it out. Sorry if this is posted somewhere else.
www.mlgp-llc.com/arduino/public/tc4-wiring-small-20111120.jpg

Picture is worth a thousand words.

-John
 
JimG
That diagram can also be found here:

http://www.mlgp-l...111120.jpg

Thank you for reminding me that it exists Grin

Jim
 
bvwelch
Open-source hardware and software platforms are wonderful -- infinitely malleable -- but can be a bit daunting at times.

great discussions here -- if in doubt, ask!

My two cents -- you can't go wrong with the TC4C. Unless you know you want to use some additional Arduino 'shields', in which case the TC4 shield is preferred since it is stackable.
 
imaroaster

Quote

JimG wrote:

That diagram can also be found here:

[b]http://www.mlgp-l...111120.jpg[


JimG - what would be changes for running a kbic-120 on DC for the fan? And then roastlogger could control both heat and fan as a stand a lone?

- John
 
JimG

Quote

imaroaster wrote:
JimG - what would be changes for running a kbic-120 on DC for the fan? And then roastlogger could control both heat and fan as a stand a lone?

Please keep in mind that I don't have any experience using the KBIC unit, and am going only on what I have read here over the past couple of days.

But if the KBIC can be configured to use a 0-5VDC analog signal as its input, then RoastLogger software should be able to control the fan directly from the I/O3 port on a TC4 shield or TC4C (I/O3 is the default fan output port for RoastLoggerTC4 firmware). It is possible that a low pass filter (1 resistor, 1 capacitor) would be needed to smooth out the PWM signal, but that should be easy to add if it is necessary.

Controlling the heater using RoastLogger/RoastLoggerTC4 is very straightforward and should require only a standard zero cross SSR of the correct rating.

If by "standalone" you mean no computer to run RoastLogger software, then you would also need an LCD display and keypad (LCDapterC, for example). The 4-button keypad becomes active and permits up/down adjustment of fan and heater output levels when RoastLoggerTC4 does not detect the presence of a connected computer running RoastLogger software.

Whew!

Jim
 
imaroaster

Quote

9.4 Voltage Following ? All models can be controlled with an isolated analog reference voltage (0 -7 VDC) in lieu of the main speed potentiometer. The voltage is connected to P2 (+) and F-. The control output voltage will linearly follow the input voltage. The source impedance of the input should be 10K ohms or less. The Min and Max trimpots are rendered inoperative in the voltage following mode. Use auxiliary trimpots for scaling and to limit the control range. If the input signal is not isolated, or is a current signal (4 - 20 mA), the KBSI-240D or SI-5 Barrier Terminal Board Signal Isolator must be used. It will allow direct connection to process controllers and microprocessor


JimG- you mention a 0-5vdc but the kblc-19pm manual mentions 0-7vdc is this a problem? Any other issues I should look out for?

-John
 
JimG

Quote

JimG wrote:
Please keep in mind that I don't have any experience using the KBIC unit, and am going only on what I have read here over the past couple of days.


OGH said the drive could be set up to follow 0-5V (at least that's what I understood). I'm taking this on faith:-)

Jim

EDIT: The "isolated" requirement may be a challenge, depending on how you are planning to power the TC4C board. Anyone know how important it is to be compliant?
Edited by JimG on 09/07/2012 9:16 AM
 
oldgearhead
If 0-7 = 0-120, then 0-5 = 0-90..
Right?
My 2-stage Amtek raises 500 grams at 53.5 volts.
Do you know the max voltage you require?
No oil on my beans...
 
oldgearhead
Isolation? Wieland is the benchmark, but you need a separate power supply...
http://www.ebay.c...4d0330cb90
No oil on my beans...
 
imaroaster
I'm really lost when it comes to this stuffBBQ grill

What about something like this? http://www.ebay.c...3cc99a1428

-John
 
oldgearhead
NO
No oil on my beans...
 
imaroaster
On an arduino forum they talked about this same issue and the on the last page he said he got his project working. http://arduino.cc...c=105828.0
Granted he is controlling a potters wheel and we are building a roaster but the parts are the same (I think)

Does this help any?

-John
 
imaroaster
Here is a thread on kblc voltage and the importance of isolation http://www.machsu...#msg153024

Once again I don't understand it so it may not help.

-John
 
imaroaster
I scored a KBSI-240D Signal Isolator very cheap ThumbsUp so this should take care of the isolation issue.

-John
 
imaroaster
OGH - could you tell me how your kb-120 is wired? Power goes to L1 and L2 but where do you connect the motor?

-John
 
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