Which Temp. Controller for Multiple Functions.

[sjlammer]

I am trying to figure out what is the most economical way to control the following processes

Switching:5500W 240V BK heating element

Switching: up to two (2) 2000W 120V Heat sticks for HLT

Switching: up to three small pond pumps for a glycol chiller

I would like to have a single temperature interface, that is expandable, but could use a PID/SSR for the 240V BK application, + somethign else for the other processes.

For these applications, I would like to have a digital display of the set point, and the actual temp. Also, I would like it to have the threaded temperature sensors like The Pol used in his set up.

What do you guys think?

 

[eccsynd]

Sounds like the perfect application for a BCS-460. It would be much more affordable than 4-6 rancos/loves/auberinstpids, plus give you a unified status and control interface. There are details in my signature.

I'd like to hear more about your glycol chiller setup.

 

[HomebrewJeff]

You may also want to take a look at BrewTroller | BrewTroller, I think it would also satisfy those requirements.

 

[BrewBeemer]

Sounds like the perfect application for a BCS-460. It would be much more affordable than 4-6 rancos/loves/auberinstpids, plus give you a unified status and control interface. There are details in my signature.

I'd like to hear more about your glycol chiller setup.

Will a pressure transducer control be added to the BCS-460?

I'm still on the fence but looking at that Honeywell LLE 305100 series liquid level photo-transistor in stainless to control the MLT level. I find this a simple trouble free unit vs a pressure sensor. Fixed vs mechanical one less item to worry about failing, getting damaged and cleaning. The $145.04 price is what's holding me back.

 

[jcdillin]

That is an interesting sensor. Do you have any datasheets on it? I couldn't seem to find much information on it with a google search.

 

[camiller]

Will a pressure transducer control be added to the BCS-460?

I'm still on the fence but looking at that Honeywell LLE 305100 series liquid level photo-transistor in stainless to control the MLT level. I find this a simple trouble free unit vs a pressure sensor. Fixed vs mechanical one less item to worry about failing, getting damaged and cleaning. The $145.04 price is what's holding me back.

That is an interesting sensor. Do you have any datasheets on it? I couldn't seem to find much information on it with a google search.

The only thing I could find is this PDF which seems to imply that the sensor simply tells you that it is submerged (or not) rather than telling you the current volume. In order to get progressive measurement you would need to mount one at say every half gallon in the tun.

 

[jcdillin]

right which is the same document I found. I thought it either implied that you had to mount them at different levels or it's possible that they put out a variable voltage based on the liquid distance from the sensor.

The full datasheet would answer that question.

 

[eccsynd]

Will a pressure transducer control be added to the BCS-460?

Yes, the Honeywell LLE 305100 is for level measurement, a float-switch replacement. Separately, pressure sensors (for volume measurement) are not currently supported for the BCS-460.

The biggest problem with using pressure sensors is that there is no 'one size fits all'. Due to the way that the calculations work, vessels with sloped sides (keggles) give different readings than straight sided vessels. And the readings can be affected by steam bubbles, probe placement, temperature differences, and even the weather outside (literally). So to get these things to work, they would have to be specifically tailored to each individual system via a very involved calibration.

I'm not saying that it can't be done. People have used them successfully in the past. See here and here. Yuri, I'd love to hear how your's are working. Also, I know the Brewtroller team is really working hard to get these sensors usable.

Physically interfacing the sensor to the BCS-460's expansion port is trivial. So the adding this capability in the future is a real possibility. All that it would take for the current community of BCS-460 owners is a firmware update. But its going to have to wait until there is a reliable, accurate, and user friendly interface available.

 

[kladue]

Implementing three wet liquid level sensors in my system was not that difficult, yes there needs to be two scale variables, one for slope bottom and other for straight sides. All three use industry standard 4-20 ma interface with 24V supply and are connected to the bottom of the kegs just below the skirt weld.

 

[eccsynd]

Do you have a link? Are they affordable?

 

[kladue]

Sorry there is no link as they were purchased on Ebay a couple years ago, the price then was under $20 each for SS pressure transmitter with NPT threaded connection. Calibration to vessel was done by adding random amount of water to keg, record start value, add exactly 1 gallon record finish value, divide for scale factor( 1 Gallon/(final-start)), apply scale factor for volume reading.

 

[MMW]

Why not take a page from the espresso guys?

Here is an interesting part. ($3)

And some pointers in the right direction:

Water level sensing
The capacitive sensor IC (which you might not even need as Arduino can do capacitive sensing right off the board...) is a QT113 from Quantum. The trick to use it for water level sensing is to set it to never time out when its sensing the water (from datasheet: set pin3 to GND, pin4 to Vdd). That is available at Saelig. Here is a tutorial for it. and the datasheet. It can we purchased from parallax. Then for the sensing electrode, get an insulated wire with a cm or so left unshielded at the end, and put that down into the water reservoir. When that unshielded tip goes dry, it will trigger the sensor.

 

[Brewers Hardware]

Why not take a page from the espresso guys?

That's a pretty cool little setup. The only thing is the BrewTroller crowd is trying to get stable and reliable volume measurement, not just level measurement. It looks like that setup will sense level at a set position.

I know in some high-end fuel tank senders they use a capacitive or resistive dip tube that the liquid floods and shorts out. When I looked into them, they were very expensive though.

 

[BrewBeemer]

Yes, the Honeywell LLE 305100 is for level measurement, a float-switch replacement. Separately, pressure sensors (for volume measurement) are not currently supported for the BCS-460.

The biggest problem with using pressure sensors is that there is no 'one size fits all'. Due to the way that the calculations work, vessels with sloped sides (keggles) give different readings than straight sided vessels. And the readings can be affected by steam bubbles, probe placement, temperature differences, and even the weather outside (literally). So to get these things to work, they would have to be specifically tailored to each individual system via a very involved calibration.

I'm not saying that it can't be done. People have used them successfully in the past. See here and here. Yuri, I'd love to hear how your's are working. Also, I know the Brewtroller team is really working hard to get these sensors usable.

Physically interfacing the sensor to the BCS-460's expansion port is trivial. So the adding this capability in the future is a real possibility. All that it would take for the current community of BCS-460 owners is a firmware update. But its going to have to wait until there is a reliable, accurate, and user friendly interface available.

My mind has already been made up on the next purchase item when my cash flow recovers, this a Honeywell LLE30510, I believe you were the one that told me about this level sensor months ago dated 2-09 on my printout sheet.
It is by HONEYWELL LLE305100 | Buy LLE305100 | LLE305100 | Onlinecomponents.com. Go to items number 201 to 250, there are many sensors to select from with lower prices with brass and plastic bodies besides different shapes. A candy store company.
We had a discussion in the past about me adding a delay timer after the sensor to send a signal preventing short and offten pump cycling.
The only problem is I like this stainless sensor at $145.04 price, I can live with the 6 week lead time. I recall Adam was the one to bring this sensor to my attention for my setup and needs. It is available in a plastic housing instead of stainless hence cheaper.
I find this a clean simple fail safe item mounted up high out of harms way vs pressure sensors as far a trouble free and possible cleaning problems or damage to them during cleaning. Also no extra holes in the MLT.
I've had it with pressure sensors on the maytag washing machine with past failures. It's mechanical has a flexible diaphragm therefore it will have a life cycling time before it fails.