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Topic: Newbie Help - Temperature sensors (Read 10801 times) previous topic - next topic

int2str

1 - yes, i like the green illuminated screen above, its more compact


A display like that is around $25.
Are you sure you wouldn't be fine with a 16x2 display? There's enough room to display 4 temperatures and they can be had for <$10?
I think they're also easier to read.... (see image below)

Which brings me to the next point:
What's your budget for this?

Quote
2 - yes as above


Sounds like you can mount the LCD & electronics yourself once received.

Quote
6 - been told a relay isnt the best thing to use, ive been told a fet should be used its solid state or something. but hey im far from an expert.


Doesn't make much difference. I'd prefer a relay because it will give you flexibility to use any fan you like down the road.
Probably something like this (2 channel to keep the future options open):


16x2 LCD:

int2str

Are those 12V power supplies?
Can the temperature controller/LCD be powered by those?

andy_con

yes mounting isnt an issue.

providing i only have one screen which can display the 4 temps at once i dont care.

the screen would need to read -

red  
blue
green
base

the the degrees symbol

that little board looks ace and flexibility of fans would be great for if i sell

no set budget, but i understand im going to have to pay for someones time to design and built a prototype.
and then the cost of additional units


1 - yes, i like the green illuminated screen above, its more compact


A display like that is around $25.
Are you sure you wouldn't be fine with a 16x2 display? There's enough room to display 4 temperatures and they can be had for <$10?
I think they're also easier to read.... (see image below)

Which brings me to the next point:
What's your budget for this?

Quote
2 - yes as above


Sounds like you can mount the LCD & electronics yourself once received.

Quote
6 - been told a relay isnt the best thing to use, ive been told a fet should be used its solid state or something. but hey im far from an expert.


Doesn't make much difference. I'd prefer a relay because it will give you flexibility to use any fan you like down the road.
Probably something like this (2 channel to keep the future options open):


16x2 LCD:


andy_con


Are those 12V power supplies?
Can the temperature controller/LCD be powered by those?


in the projector is 12v 3amps and 5v 8amps

sadly the 12v is pretty much used so i suspect ill have to get a small dc to dc converter. but dont worry about that, thats my issue to sort and its easy to sort.

this projector is my first one, so little issue like power supplies i need to address or the next build

andy_con


int2str


so where from here int2str?


I ordered a 20x4 LCD display and temperature sensors. Should be here in 3-4 days.
I will prototype it up and if you like what you see, I'll solder it up and ship it over.

andy_con



so where from here int2str?


I ordered a 20x4 LCD display and temperature sensors. Should be here in 3-4 days.
I will prototype it up and if you like what you see, I'll solder it up and ship it over.


rough idea on total costs?

int2str

rough idea on total costs?


First off, while I have ordered the parts already, you (or I for that matter) are not in any way committed. Like I said, I will prototype it up and if you like what you see, I'll solder it up and send it to you. If not, no harm, no foul. All the components I've ordered (LCD etc.) are very useful for other projects I'm doing anyway, so don't feel obligated :)

Also, I'm actually thinking about using an ATTiny85 for this. I have a few laying around and they are very easy to use.

Material cost so far:
$25 LCD
$10 4x Temp sensors
$2 ATTiny85
$5 Relay module

So, total spend so far is $40 with the bulk going to the LCD.
Add ~$10 for a circuit board & misc items. So ~$50 should cover it.

andy_con

that sounds an excellent price, i cant wait to see it up and running

one thing, we have our next laser gathering on weekend of 21st sept, id love to have a working unit i could take and show off/demo ;-)

cheers

int2str

The LCD display and temp sensors came in today already.
The display is really nice and super easy to work with.

I forgot that the ATTiny85 only has 3 usable ADC pins (without using a HV programmer). So I'll be using an ATMega328 instead. That adds about $2 to the price, but keeps the options open for future expansion.

I ordered the temperature sensors in a TO-220 package.
This means they look like this:


I did this because it enables you to screw the sensors directly to the lasers or zip-tie them. Not sure how you're planning to mount them.

So, here's what it looks like so far:
http://www.youtube.com/watch?v=J7ardMN20pA

Let me know if that meet your requirements or if you want any changes.

andy_con

first things first that looks fooking awesome!! :)

to be a pain any chance of using different sensor, i should have gave a tad more info on that part.

what i plan to do is drill a small hole in the side of a laser module and mount the sensor in there with some thermal paste.

ive seen some small 2 pin sensors but dont know what they are called so cant link to them :(

int2str

to be a pain any chance of using different sensor, i should have gave a tad more info on that part.
what i plan to do is drill a small hole in the side of a laser module and mount the sensor in there with some thermal paste.


How big are the laser modules?
What's your definition of "small" hole? :)

The sensor I used also comes in a TO-92 package. That looks something like this:


The head is about 4.5mm in diameter.
Is that small enough?

What you're referring to is a "thermistor". They do come in even smaller sizes. The problem is that they are usually non-linear and require calibration. In other word, they are less accurate and harder to use.

andy_con

Modules look like this, base late is 10mm thick so those would probably do


andy_con

do you have any photos of the complete setup so i can get an idea of size?

int2str


do you have any photos of the complete setup so i can get an idea of size?


Nope, not yet. Still have to figure it out how to put it together, too.

Here is the datasheet for the display:
http://www.newhavendisplay.com/specs/NHD-0420D3Z-NSW-BBW-V3.pdf

It has all the dimensions you need for the cut-out, mounting holes etc.

We have two options as far as mounting the controller goes:
1. "Backpack" it to the back of the display. Using stand-offs and attach the controller board right to the back of the display. That way it will be just one unit and you only have to worry about mounting the display.

2. Keep the controller board separate and just run a wire to the display. The controller board will be much smaller than the display board is, so it should fit pretty much anywhere.

Let me know which option you prefer.

Also, the controller and display need 5V. Do you want me to solder a voltage regulator on the board or are you going to take care of it somehow?

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