I am planning on building a small personal brewery that will fit in my garage.

This will be done using the all-grain mashing technique which usually involves having 3 kettles that contain grains with hot water (150-180 degrees) or just hot water by itself. Initially the 1st kettle will contain hot water, the 2nd will contain hot water with grains, and the 3rd will be empty. The process is to cook the grains in the 2nd kettle for a set period of time (roughly 1 hour) and then filter the water from the grains and transfer it to the 3rd kettle. Next, the hot water in the 1st kettle is used to rinse the grains in the 2nd kettle and then filter into the 3rd kettle. Finally all initial liquids are transferred from kettle 1 & 2 into kettle 3.

A small pump will be used to transfer the liquids from kettle 2 into kettle 3. Gravity will allow liquid from kettle 1 flow into kettle 2 as it is higher in elevation than the other 2 kettles. Right now I am will be using manual ball valves to control the flow from kettle to kettle.

What I would really like to do is be able to automate the process of transferring the liquids from kettle to kettle using the pump. I imagine I would have to replace the ball valves with solenoids valves, along with adding some kind of water level sensors. Also I would like to be able to run the automation process from a PC. And lastly, I am working with a budget (meaning I am willing to spend a few hundred $), since it will be a weekend hobby for now.

Here are a few questions I have:

1. Having no experience in controls, my question is how would I go about linking a PC to the pump, solenoid valves, and level sensors?

2. I have read about USB data acquisition boxes that sound like something that might work. Can these be used to control the valves and pump in an on and off fashion?

3. It seems like the control would have to be based off of the time the liquids have be cooking to begin the transfer process, would this USB device also keep track of time?

4. Would I have to develop my own program to run all this... I have not much experience in programming either.

Any information/guidance would be appreciated.

 

There are pc cards. That you can add to your pc and some cards have i/o and anolog i/o. B&b Electronics or Jameco. If you need help with programming let me know.
Searching the internet will find many cards.

Retired
[email protected]

 

Mr. Van Winkle,
Interesting project.

You might accomplish this as a timed process: (1 hour soak, 2 minute transfer, 50 minute soak, 2 minute transfer, 30 minute soak, 2 minute transfer; for example) and avoid the lessons of field instrumentation - like level sensors.

Although I've done industrial controls for 25 years, I have yet to use a PC for control. The problem with PC control is what is called I/O - inputs or outputs that are electrical signals: inputs like level or temperature, outputs like "turn the pump on" or "close the valve". Digital outputs, abbreviated DO, are used to switch a pump on or off.

You broached the topic of I/O with your mention of USB. I am clueless on USB I/O. The dinky little connector is useless in industrial applications (no way to fasten it so it doesn't fall out). Someone else will have to advise you on USB I/O.

A common industrial alternative for PC I/O are I/O modules that talk an industrial protocol known as Modbus that communicates over an RS-232 port (which is what the serial port on a PC is) or RS-485 (which needs an 232/485 converter to work on a PC serial port). The catch is the software. You need software to program when the pump turns on, when the valve turns off, etc.

Software to monitor or control I/O generally falls under the category of SCADA or HMI software. Since software like this is typically sold to people who have expensive capital equipment and need to meet production schedules, it isn't software on the cheap. I know Advantech makes Modbus I/O modules for $300-500), but their Studio software is over $1,000.

If you find a USB solution, be sure to check what kind of software is offered. Your question on whether the software keeps track of time is exactly what you'd have to find out. I take it that you aren't ready to write your own control programs in C.

I have two alternative suggestions to USB - discrete controls, a timer and some relays, or a programmable logic controller.

If the process is strictly a timed process, you can do it with timers that cost $60-100 each and relays that cost about $20 each. Industrial supply houses (distributors) have industrial models, the 'light' timers one buys at Home Depot might not have enough resolution and are generally 24 hour timers. Everything gets wired with what is called "relay logic".

An alternative is a programmable logic controller, dedicated industrial controllers. These devices have multiple timers built in, and have I/O designed to do things like sense a high level switch and close a switch that would close a valve. The PLC is the controller, you'd still need a pump or a solenoid valve, the PLC tells the pump when to turn on or off.

One advantage of a PLC is that it is easy to re-do a program, without rewiring the timers or relays.

The disadvantage of a PLC is that you have to program it to make it work.
PLCs.net sells a tutorial book and there are text books on the subject.
Many community colleges in the US offer a course in PLCs or industrial electronics. The advantage of a course is having others you can talk with to help you in your task.

I've never used the brand, but I read lots of compliments about Automation Direct, a mail order PLC distributor. They have low cost hardware and my impression is that the software needed to program the PLC is low cost, too. Be wary of used PLCs, the cost of the programming software can be well over $1,000.

Bud

 

On August 19, 2005 21:57, Joe Van Winkle wrote:
<clip>
> 1. Having no experience in controls, my question is how would I go about
> linking a PC to the pump, solenoid valves, and level sensors?

There are many ways, and the best way depends upon the size, location, and type of actuating power the device uses. Essentially though, you need an interface board or box which your PC can talk to, to set outputs and read inputs (see below). You also will normally need some sort of relays or solid state relays to convert the voltages (and current) between what the interface
box or board can handle, and whatever the field devices (pumps, sensors, etc.) require.

> 2. I have read about USB data acquisition boxes that sound like something
> that might work. Can these be used to control the valves and pump in an on
> and off fashion?

Yes, but you will need some relays or solid state relays (for on/off type signals), or signal conditioners (for analogue readings of things like temperature) as well. The USB devices are generally not as good as some of the alternatives, but are likely more than good enough for what you need, and probably would be within your budget.

> 3. It seems like the control would have to be based off of the time the
> liquids have be cooking to begin the transfer process, would this USB
> device also keep track of time?

No. Your PC program will have to keep track of time.

> 4. Would I have to develop my own program to run all this... I have not
> much experience in programming either.
<clip>

You may have to develop your own program if you can't find one ready made. I would suggest that you do an internet search (e.g. Google or Yahoo) for micro-brewery hobbyist sites. I wouldn't be surprised if there was package available off the shelf for this sort of thing. You may also find other hobbyists offering free designs and software.

 

Hi,
An absolutely perfect candidate for LOGO! or similar programmable relay. Download and read the documentation, look at the examples, It can be programmed from the front and can display times and messages. Also contains a real time clock. I'm sure that the first few batches will not be perfect, but I could help you dispose of them!!

http://www.siemens.com/logo

Marc

 

At http://www.hottimesoftware.com/ there are a number of downloads that can be used.

The timing can be achieved, to operate solenoids or pumps at different times via the parallel port. A level sensor can be connected to control the "on" or "off" of your solenoids as an input.
This software is low cost and can be connected to kits or a PLC.

 

Another idea would be a low cost data acqusition & control package such as DAQFactory from AzeoTech. This software will work with a USB device called labJack. I have used Labjacks with great success, but I have not tried DAQFactory. Here is a link to Azeotech:

http://azeotech.com/products.php

The Siemens LOGO controller is a also a good suggestion, but it is not PC based. It would probably be a quick method to achieve basic automation.

I was also going to suggest a DL05 or DL06 PLC from Automation Direct. You might be able to find a low cost PC front end that will connect to the DL05.

Here is a link to the DL05: http://web6.automationdirect.com/adc/Shopping/Catalog/PLC_Hardware

 

Be aware that many electric or other types of valves and fittings are not designed for food type applications and can allow product to accumulate in various internal and external cavitites. Over time these accumulations can introduce some pretty wild bacteria into your final product. If the downstream stages of the process are not able to kill off these bacteria, this of course can present serious health risks. You could find yourself with a food poisioning situation. I am not familiar with the brewing process, but you may want to keep this in mind as you design you system.

Sounds like you are about to learn a lot... have fun! Think SAFETY!

 

Joey,
Your best bet is to buy a Data Acquisition card that goes in your computer and send all valve on-off signals, pump on-off signals out through it. you can also get signals from sensors and use them in your program through the Data Aquisition Card (DAC).

An easy way to program the whole system is to use LABView from National Instruments www.ni.com. They also sell the DAC. However, this option may get kind of expensive.

Alternatively, you could use a microcontroller and program it in C or Assembly language. This would be cheaper, but it would take you longer to get going.

This is not too difficult a project if you are not trying to control mass flow rate, temperature, pressure, etc. If you only want to turn devices on and off on a set schedule or in response to sensors, it's pretty easy.

This would be a good exercise for a mechanical engineering instrumentation lab.

 

If the application is really simple, the Parallel port on a standard PC will work.

(Fewer than 8 Valves and Fewer than 8 sensors, and Timing is quite easy.)

I use QuickBasic for this type of work.

This is a very rewarding approach if you have a liitle time to learn the rudements of Basic.

Todd