Aussiedistiller, Home Distilling, Moonshine, Home Brew

Soo.. burnt my stc sensor probe cable on a hotplate today, nothing major as is just one of the wires exposed but i want to replace it.
this is the one i have, same ebay page. mentions NTC sensor so i ebay searched for that
http://www.ebay.com.au/itm/Digital-STC- ... Sw37tWCktX


Wondering what people think, is this a good probe to replace it with. looks exactly like the one on it now only its 5m instead of 1m or so that i have.

http://www.ebay.com.au/itm/5M-Long-NTC- ... xycgVThYSY

Cheers
WTD

Hey WT, couldnt you just splice the wires with an extension cord and use heat shrink?
The wire thickness 'looks' similar...5 bucks, or less, cheap fix.

sorry, didnt look at the second link...8.60 cheap... it just the wait yeah?

waiting isnt an issue. getting a good probe is. can get them for $1 from hong kong and no shipping but how do i know it if is accurate.

Im thinking now I should cut my sensor cable and just using male and female crimps to rejoin the wires, and/or the heat shrink plastic as my sensor is fine, just a little bit of wire exposed. assuming i can shrink it with my map holding it a substantial distance away underneath :shifty:

The length isnt long already and if i cut out 3cm then there goes a bit more. Im wondering if i can just use some 1.5mm cable and lengthen the cable myself or should it really be a thin cable like the sensor. looks ultra thin.

does thicker cable give off different reading or is it just thin because of the such small voltage in it and they use small cable to cut costs, meaning i can touch it while on and nothing happens.

If adding some length myself is 1.5mm cable ok?
Or, should i get something smaller from jaycar like maybe this... http://www.jaycar.com.au/fig-8-white-ac ... e/p/WB1560

aside from ebay i rang around and a shop near me has them. about $30, yea right could buy 2 new STC's for that

Cheers
WT

If you are going to Jaycar, why not just get a couple of connectors and put them in where the damage is,
You could get a couple of extra connectors and some wire and make up a jumper wire to extend it as well
so you would end up with a normal length and an extender.

A PTC is " Positive Temperature Coefficient " and a NTC is "Negative Temperature Coefficient" one goes up
in resistance with more heat while the other goes down in resistance.

Should work as long as you do not put any resistance in the circuit.

Toyoda

cheers, ill do that, does wire thickness matter? i mean if its thicker than the original. i always looked at it as a larger diameter was for more flow but having larger doesnt hurt.
Is this right? ill get connections and wire from jaycar. just wondering if size matters? Im doing my bachelor in power engineering but still in my infancy in that

The thicker cable would have lower resistance meaning it's less likely to adversely affect your readings.

I've spent the last 2 hours trying to find my good multimeter with no luck :angry-banghead: I was going to measure the resistance on an STC-1000 probe I have here too see if it's the same as the replacement one you found.

I'd probably use a soldering iron or maybe a heatgun (the wife's hairdryer?) over mapp gas to heatshrink on cable that small, don't want to melt more of it :teasing-tease:

lol ok, originally was going to hold it a foot below but ill get the hair dryer, does it not take too much heat to shrink? been years since i used it in school

So on a revised look I found the bloody multimeter (only coz I announced I couldn't find it I'm sure....), the STC-1000 probe measured at 11k ohm which is pretty well close enough to the 10k ohm one you found.

I also found some wire exact same size as on the probe, if you want I can solder some more wire on and heatshrink it aswell? I'm on the south side of Brissy

Cheers, ill give it a go myself. Need the practice since ill be doing alot of it. also enjoy making it myself. Pretty sure one of my next courses requires me to get a soldering iron n stuff for uni.
Thanks for the offer :handgestures-thumbupleft:

No worries, if you do your trip to jaycar they have the matched size wire on small spindles. Happy soldering :handgestures-thumbupleft:

Stc 1000 has a calibration adjustment.
Chuck it in ice water and calibrate it to zero or boiling water and cal to 100. +/- 10 degrees.

what is ice water? is it a jug of water filled with ice to make it really cold? is that 0 degrees C?

Yep,

Agree with the above posts - Thicker wire has less resistance so should not affect reading. :roll: Heaps of Caveats here - wire material/number of strands/size of strands/insulation thickness !

Soldering is easy just tin the wires first.

Toyoda

use a ciggy lighter for the shrink sleeve. NO MAP

What is STC?

While I'm asking stupid questions...
Why use voltage controllers instead of just turning elements etc on and off?

Sorry for the noob questions.

I'm not doing any electrical work, just trying to learn.
I'm actually an apprentice EFM but get no exposure to this type of stuff and have no idea
what the guys in this section of the board are talking about.
I probably should though.

Thanks

Simon

An STC1000 is a model of temperature controller frequently used to modify fridges for constant brewing temperature.

Voltage regulation is better than switching the elements on and off for maintaining a constant temperature. When the element goes off the temperature starts to cool down until you get to your lower set point (assuming you are using a temperature controller of some sort) and it switches back on, this still takes time and temperature continues to drop until the element switches on full power and heats up again. The overall effect gives temperature fluctuations that look like a roller coaster.

By using voltage regulation you can set your element to run at a percentage of full power and keep it there and maintain a constant temperature.

Hopefully that doesnt sound too rambly and makes sense.

Do you also need to limit the current?
Or will current remain constant even at a lower voltage?
Regards

Simon

If it was me i would
Solder all joints as connectors, crimps can increase the resistance and introduce an error that will change with time as they corrode or become loose.

The length of wire can be changed if checked for accuracy, use any size of cable as there is very little current flow,

Note: some thermocouples require special cables