motor dimmer or light dimmer to control crockpot temp

Ok I am in the process of trying to automate home made yogurt. I need to maintain the temp of the milk at between 100 and 110 degrees and hold it there for 8 to 12 hours. If I get to 120 degrees the yogurt bugs die and I get no joy. I have wanted to use my small crock pot but at the low setting it gets above the 120. So it got me thinking why not put a dimmer in line with the crock pot and dial in the lower temp with it. It then occurred to me there are motor dimmers and light dimmers and I am not sure what to use. My first thought is to use a light dimmer as the heating coil in a crock pot is nothing more than a giant filament.

What do you all think

As much as I enjoy reinventing the wheel, there are quite a few purpose built yogurt makers out there that start at around $20.

Ya but that is no fun and I really don't like things in my kitchen that only do one thing. No uni taskers allowed my kitchen.

Bread makers, yogurt makers and the like are not welcome. The only one that I have allowed is the keurig and it makes tea and coco so it is borderline ok.

for what it is worth, there are rotory and slide dimmers that can take high amperage.. but that should not be a problem for you. A home crockpot plugs into a 15amp circuit, so a regular wall dimmer might work if you build it into a metal box and use proper cords.

The only issue I see is you will then have two dimmers in line with each other (the one feeding the crockpot and the one built into it) so I am not sure what that will do. It will -not- be good for the controls of the crockpot. I have never taken one apart, but I wonder if you can gut it and just run it straight off of the mains and just use your new dimmer to set temps

Dimmers do not like big resistive loads...

It's a good way to start an electrical fire.

Your average knob-type household dimmer is only good to about 600 watts.

Check the rating on whatever you're using to reduce the current to the crock pot.

I wonder if the hi setting is strait through with out any reduction in power and the low setting is really the only built in dimmer.

Mine has three settings: "keep warm" "low" and "high".

The manual says that "Low" and "High" will ultimately reach the same temperature but "low" will take six hours to get there and "High" will take three.

Not sure if that helps or not.

Shawn

Dimmers use a triac to clip the incoming AC waveform. The chopped up sine wave may cause issues with a newer crock pot with "smarts" built into it. On older crock pots the dimmer may work.

I fail at hotlinking most of the time, the picture below shows how the waveform is modified by a dimmer. http://wiki.dxarts.washington.edu/groups/general/wiki/4dd69/images/3f9a9.jpg

we have some high power dimmers at work that are rated to 20amps.. I will try to find out who makes them tonight.

Worst comes to worst.. get an autotransformer!

Why not get a proper temperature control setup? I think you can get them or build them pretty cheap. Even with a dimmer, you're still going to be fiddling with things to try to get an even temp in the range you want, and outside influences like ambient temp will affect your settings.

You don't want a dimmer, you want a thermostat.

Kenny_McCormic wrote: You don't want a dimmer, you want a thermostat.

very interested in this. Got a link or somthing I can look at?

Chobani!

My opinion is that you can spend time and/or money in an effort to modify a tool not designed for yogurt making such that it may or may not work as intended, or you can get the right tool for the job.

In this case the latter solution is also likely the cheaper solution.

So you can put me down in Bumboclaat's camp.

Something like this would work http://www.amazon.com/Johnson-Controls-Digital-Thermostat-Control/dp/B00368D6JA/ref=sr_1_1?s=home-garden&ie=UTF8&qid=1419959424&sr=1-1&keywords=temperature+controller

Bumboclaat wrote: As much as I enjoy reinventing the wheel, there are quite a few purpose built yogurt makers out there that start at around $20.

I'm all for using ingenuity and making modifications, but in this case I would save the hassle, time, possible fire hazard, and spend $20 to get a yogurt maker.

dean1484 wrote: Ok I am in the process of trying to automate home made yogurt.

My brain must be in a weird place, because this made me start to think about manual transmission yogurt.

This for $15.00, set it and forget it.

110V Temperature F Controller Temp Sensor incubation thermostat Relay

•Measure range: -4°F~+194°F •Slew range of temperature: 1°F-30°F •Resolution: 0.1°F •Accuracy: ±1°F (-4°F~150°F) •Power supply: 110V AC, 50/60Hz •Power consumption: less than 3W •Relay contact capacity: Cool(10A/250VAC);Heat(10A/250VAC) •Data retention: Yes •Compressor delay protection: YES

http://www.ebay.com/itm/Fahrenheit-110V-Temperature-F-Controller-Temp-Sensor-incubation-thermostat-Relay-/281294885235?pt=LH_DefaultDomain_0&hash=item417e7b5173

If you are going to automate it, make it automatic.

Toyman01 wrote: This for $15.00, set it and forget it. 110V Temperature F Controller Temp Sensor incubation thermostat Relay •Measure range: -4°F~+194°F •Slew range of temperature: 1°F-30°F •Resolution: 0.1°F •Accuracy: ±1°F (-4°F~150°F) •Power supply: 110V AC, 50/60Hz •Power consumption: less than 3W •Relay contact capacity: Cool(10A/250VAC);Heat(10A/250VAC) •Data retention: Yes •Compressor delay protection: YES http://www.ebay.com/itm/Fahrenheit-110V-Temperature-F-Controller-Temp-Sensor-incubation-thermostat-Relay-/281294885235?pt=LH_DefaultDomain_0&hash=item417e7b5173 If you are going to automate it, make it automatic.

I am going to order one tomorow. That looks like exactly what I am looking for.

I will post up results.

I can put the sensor in the water bath in my large crock pot and it will allow me to make half gallon batches with ease.

I looked at automated makers in the $20-$30 range and they all had these little 8 ounce glass containers. I want to make it in a single container. I found one that did this but they wanted $135.00 for it.

Ok got one on the way. That is a really cool device. I can see other uses for it as well. Like using it to cool electronic equipment.

Got the new gizmo yesterday and wired it up. Will test it tonight. They also make 12 volt units that I can see some really cool automotive applications for.

I used something similar to record EGTs on the gas turbine I built. They are hard to beat for cheap temperature control.

The wiring instructions were not clear but after I figured it out it is the coolest thing. I am thinking of getting a coupe more. I could use it to add a small fan to my entertainment center's in the living room and in the family room to monitor the heat in the cabinet and then cool it if things get above say 100 deg. (PS3's run very hot as do other entertainment electronics)

I was also thinking that it would possibly be neat to put a small fan on my base board heating and when it censes the heat coming on it would start a small fan that pushed air through the base board. Don't know if it would actually save any $$$$ but it would sure cause a room to heat up quicker.

I could put it to a fan in the attic to monitor temps up there and automatically cool it when temps get to hot in the summer keeping temps down in the upstairs bedrooms.

This is just what I can think of at the moment.

EDIT: They also sell 12 volt versions that I can see a bunch of applications for cars. You could add cooling fans to things. Monitor temps and manually trigger a 2nd cooling fan. Put a small fan on the trans cooler on my truck that is controlled by this.