# [SS2S-Main] Re: temperature controller with arduino

• From: Vicente Alvero Zambrano <vicente_alvero_14@xxxxxxxxxxx>
• To: "sugarshot@xxxxxxxxxxxxx" <sugarshot@xxxxxxxxxxxxx>
• Date: Sat, 28 Jun 2014 18:37:10 +0200

```Hi Tim,Any news?

From: vicente_alvero_14@xxxxxxxxxxx
To: sugarshot@xxxxxxxxxxxxx
Subject: [SS2S-Main] Re: temperature controller with arduino
Date: Wed, 25 Jun 2014 11:06:02 +0200

Sorry for the delay Tim, I've been busy these days. I'll try to answer your
questions.
1) What is the weight of the heaviest item you envision heating? In principle,
the heaviest element we want to cure is the nosecone. I do not know exactly the
weight of this piece because it is not yet defined. Say, as long long, 3 kg.
2) What is the specific heat of the materials used?
I do not know the specific heat of fiberglass fiber, but maybe we can make an
approximation
3) What is the maximum temperature required?
With the current resin we are using, the maximum curing temperature is 80 ° C.
But we have used resins with a maximum curing temperature of 200 ° C.
4) What is the maximum rate of temperature rise per min or per hour?
Approximately, the temperature rise is usually 10 ° C / h
5) Will you be doing this work in Europe?   I need to know what type of power
source you have available. Voltage and Amperage on the circuit you plan to use.
In Spain, the voltage is 220V with a frequency of 50HzFrom: tyoung489@xxxxxxxxx
Date: Mon, 23 Jun 2014 00:26:26 -0700
Subject: [SS2S-Main] Re: temperature controller with arduino
To: sugarshot@xxxxxxxxxxxxx

Vicente,

To

1) What is the weight of the heaviest item you envision heating?

2) What is the specific heat of the
materials used?3)
What is the maximum temperature required?4) What is the maximum rate of
temperature
rise per min or per hour?

5) Will you be doing this work in
Europe?   I need to know what type of
power source you have available. Voltage and Amperage on the circuit you plan
to use.

You
gave 100 C as the max temperature required. I could not find any epoxy systems
that recommend such a low curing temperature.

I
see 120-C to 180-C for Epoxy, 150-C to 180-C for Phenolics, and up to 290-C for
Polyimides

For Epoxy I see 1-C / Min to
5-C / Min rise.
This is 60-C to 300-C
per hour.   This is very different from
the example you gave.

example:

20 ° C to 100 ° C by increments of 20 ° C / h.

5 hours at 100 ° C.

100 ° C at 20 ° C with a decrease of 20 ° C.

Ideally develop a graphical interface to vary these parameters at will.

On Sun, Jun 22, 2014 at 2:47 AM, Vicente Alvero Zambrano
<vicente_alvero_14@xxxxxxxxxxx> wrote:

Hi Tim,
Unfortunately, we can not spend \$ 180 on this system. On the other hand, given
that the PID is the best option, we can opt for this.
We have a PID we bought last year. PID is REX-C700. I also have a thermocouple
type K 2 meters in length. So we can use this.

Now the question is, what fan?, What resistance?, What power?

From: tyoung489@xxxxxxxxx

Date: Sat, 21 Jun 2014 21:04:29 -0700
Subject: [SS2S-Main] Re: temperature controller with arduino
To: sugarshot@xxxxxxxxxxxxx

Hi,

Depending on how you locate the heaters you may find that you'll have
problems maintaining uniform temperature throughout the oven with your
planned dimensions of 2 x0.5 x 0.5 m (Free).  Long oven shapes are more
difficult to keep at a uniform temperature.   Long oven can be beneficial if
you have a process that requires different temperatures along the route
through the oven tunnel.   In a tunnel oven you are normally applying spot heat
directly or via infrared.

In a convection oven, like what you want, the heat is applied indirectly
via the surrounding medium, air in this case.   Normally the heat
source is not directly in the area with the product your heating. You want
some heat barrier (wood, steel, or aluminum plate) between it & the product to
avoid spot heating.   Larger ovens would use a supply fan with
additional stirring fans to maintain uniform temperature.

Just for consideration.  This could all be inside your plywood &
foam box. Heater section with stir fan(s) -> Aluminum plate barrier to
direct heating -> oven space with stir fan(s).   Also you can often get lower
cost fans if the motor is mounted outside the oven with only the blade in the
heated space.

The control portion of your job requires nothing unique that requires
new research or development efforts.   This is a straight forward case
of application engineering for this cure oven.

It
seems to me that with the Arduino you're starting from scratch to
re-develop the wheel.  This may be fun but is unnecessary with the
abundance of low cost, off the shelf controllers, & software
available.  Granted these weren't available 20-years ago but neither was
the Arduino.   The design, testing,  & debugging of the software
interface for the controller is where
you'll be spending or wasting your time, depending upon the results.

The BCS-460 is a fully debugged Temperature Controller with Everything you want
& much more. \$180.

Graphical, Web, & Smart Phone Software Interface.

8 Programmable outputs each with 8-stages.

4 Sensor inputs

You can pre-program & also interact with the settings on the fly.

http://www.embeddedcontrolconcepts.com

Graphics Screenshots

http://www.embeddedcontrolconcepts.com/screenshots.html

The BCS-460 has 4 temp sensor inputs.   These are any ntc 10k ohm
thermistor that you can get 100 for \$8 plus shipping online or \$0.75ea
plus shipping from SparkFun.

For your curing operation you will want to know the temperature of the
part, not just the oven temperature.   What is often done is to use a
scrap or dummy piece of what you are curing & embed the sensor at
the spot that the temperature is most critical to sense

BCS-460 Controller  Graphical, Web, & Smart Phone Software Interface
(These will do what you ask of them. Don't get tripped-up by what
they're called. Curing a composite part is less sophisticated than running a
Brewery)

https://www.brewershardware.com/BCS-460-Brewery-Control-System.html

iPhone Interface Demo

Software Documentation

http://wiki.embeddedcc.com/index.php/Main_Page

Other Electronics starting around \$15 (some of these have the ability to output
to your computer some come with software)

http://www.ebay.com/sch/i.html?_trksid=p2050601.m570.l1311.R1.TR8.TRC1.A0.H1.Xpid+temp&_nkw=pid+temperature+controller&_sacat=0&_from=R40

On Sat, Jun 21, 2014 at 4:02 AM, Vicente Alvero Zambrano
<vicente_alvero_14@xxxxxxxxxxx> wrote:

Hi,
The main idea is to made a home oven from plywood and foam insulation. I
planned dimensions of 2 x0.5 x 0.5 m (Free). With these dimensions we can cure
any parts necessary for SS2S project. Recall that the largest piece so far is
the nosecone (1507 mm).

For smaller piece, and in order not to waste energy, I have thought the
manufacture of a partition.
You're right about the fans. I'm sure I can get some free fan oven, as well as
resistence.

The objective of using arduino, is the possibility of developing a graphical
interface in which to determine the temperature rangesSubject: [SS2S-Main] Re:
temperature controller with arduino

From: tyoung489@xxxxxxxxx
Date: Fri, 20 Jun 2014 17:30:38 -0700
To: sugarshot@xxxxxxxxxxxxx

As much fun as it is to play with Arduinos it's a waste of time &
money.Programmable PID Temperature Controller with single or dual sensors can
be purchased on eBay for \$15-\$60.

Where will you be placing the temperature sensor for the controller, embedded
in the part or on the surface? Or are you going to try to run the oven at the
desired temperature and guesstimate the time it takes for the part to
equilibrate? I believe that would problematic and take longer to achieve your
cure. I think that the manufacture of the composite materials should be able &
more than willing to provide you with general propose curing methods &
procedures.

Are you building your own over with strip heaters, fans, etc? Or are you
planing to interface the controller and fans to an existing oven?
For convection circulation you only need constant speed fans and if you plan on
using axial flow computer type fans be aware most are rated to 60-C or  70-C.

You can get 105-C rated fans but not from an old computer. sofasco.com is one
of many places you can get them. You could use standard fans but it anyone's
guess on how long they'll last.

If the parts are small you can buy small electric convection ovens sold as
Toster/Pizza ovens.Check Walmart, Best Buy, Target, eBay, Amazon.

On Jun 20, 2014, at 4:01 PM, Vicente Alvero Zambrano
<vicente_alvero_14@xxxxxxxxxxx> wrote:

Florin that's perfect. The system must be simple (as cheap as possible). With a
source of heating (resistance) and several computer fans to circulate the air.
Arduino must be able to control the temperature (using the resistance and the
fan) according to a predefined schedule. A program is for example:

20 ° C to 100 ° C by increments of 20 ° C / h. 5 hours at 100 ° C. 100 ° C at
20 ° C with a decrease of 20 ° C. Ideally develop a graphical interface to vary
these parameters at will.

Date: Sat, 21 Jun 2014 01:32:37 +0300
Subject: [SS2S-Main] Re: temperature controller with arduino
From: florin.mingireanu82@xxxxxxxxx

To: sugarshot@xxxxxxxxxxxxx

I can help with the temperature controller but I would need more precise
specifications: like temperature range, control "band" etc.

On Fri, Jun 20, 2014 at 10:16 PM, Vicente Alvero Zambrano
<vicente_alvero_14@xxxxxxxxxxx> wrote:

Hi,Anyone know how to make a temperature controller with arduino to make a home
oven to cure composite? The idea is to monitor several computer fans and
thermal resistances. Must be able to follow a cure profile and decreased with
increases in temperature curing.

Any volunteer?
CheersVicente Alvero

--
Florin Mingireanu
Romanian Space Agency
Str. Mendeleev 21-25, et. 5, sector 1, 010362 Bucuresti, ROMANIA
office tel. +40-21-316.87.22; +40-21-316.87.23;

cell: +40-757-768971 (primary phone)
fax +40-21-312.88.04
florin.mingireanu@xxxxxxx

http://www.rosa.ro

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