Hi,

Yes, the best way is trial and error. Unfortunately this is the best way as there is no marking on the sensor itself. Even it it had one, the sensor is typically hidden in a thermowell/probe, etc. The interface polls the 1-wire sensors on the bus at start-up and assigns indexes then. They will not change as long as new sensors are not added or deleted.

You can assign any index# to any port#. The reason for both is it allows you to easily change the index when you add or delete 1-wire sensors and the index's change.

Please let me know any questions or concerns and I will try to help you. 

I'm sorry but I can not see where my question was answered. 

tracer

My apologies... I hope I understand your question better here.

1-wire sensors are indexed upon interface boot-up. They are indexed from 0 upward. So if you have three sensors, their indexes will be 0, 1, and 2 respectively. 

In each 1-wire device element, you would select the index of the sensor you want that device to display.

Which physical sensor belongs to which index needs be determined by trial and error. 

That answer your question? If not, please rephrase and I will try again. 

BD  I tried for several hours to get my 1wire sensors to display the temp without any luck.

The only way I can get them to display any thing is to disconnect all but one and set it as 0 . When doing that I can get all four of them to display the temp, one at a time. I thought I may have a bad mega but I'm 0n my third one now and still not able to display more than one temp.  The one probe that I have  displaying now I have set to control the boil KET but nothing happens.  It shows the temp of the probe the set point of the boil and the output  but nothing happens.  Have you tested with more than one probe?

Still an a loss  tracer

Hi Tracer,

I can appreciate your frustration. Trust we'll figure it out. Yes, the system will work with multiple sensors. Here is my list of ways to resolve this.

1. The probable culprit is wiring or a bad sensor - I know this is obvious and likely something you checked but nonetheless we need to check. There must be a reason 1 works at a time but not together. Make sure the sensors are wired per the schematic. All sensors' grounds are tied together and to a MEGA GND pin. All sensors' +5V lines are tied together and to the +5V from the MEGA on the 5V pin. The sensor's data lines are tied together and connected to pin 5 only. There needs to be a 4.7k resistor tied between +5V and the data lines. These must not be wired in parasitic mode. The wires must be short (<3m) and properly terminated. The power supply must be clean - I suggest you power the MEGA with a proper 12VDC regulated power supply into the 2.1mm jack or into the Vin PIN. Powering the MEGA with your computer's USB port may induce electrical noise.

2. I suggest we isolate one sensor at a time to make sure they each work individually. It sounds like you did that but I recommend you wire one sensor and check that it is responding. After wiring, the MEGA must be reset. Better, it should be powered down and restarted. The devices are identified/enumerated upon micro-controller boot up only. When you restart it, reconnect BruControl but use the same 1-wire device element, with the index set at zero. Because each time the MEGA starts, it will enumerate the first (in this case, the only) device as index 0, it will not change from test to test. Once you find that all four work individually, test again with two at a time, then if working, try three, then four. Per above, each time you add a sensor (don't forget to restart), each device element will need to be set to a unique index - so 0, 1, 2, etc.

3. If that does not work, I will send you a special diagnostic firmware that will read and report the 1-wire sensors on the bus. This would completely isolate BruControl and boil it down to just the hardware alone.

4. I am not sure I understand your comment about the "I have set to control the boil KET but nothing happens". What type of device are you using? Hysteresis, PID, etc? Make sure if you upgraded the Firmware to version 41 you also download the latest version of BruControl because the hysteresis mode was changed, and they are only compatible with each other. The Hysteresis and PID outputs will measure the selected input against the target and affect the output accordingly. The device element will report the output status (ON/OFF for hysteresis and % output for the PID). PID outputs will use PWM if the output port supports PWM and duty cycle (on/off) if the output port does not support PWM.

5. If you like, we are happy to speak with you live. Contact us at info (at) brucontrol.com with your number and a time to call and we can connect that way.

I will check all of the wiring again. I have a hard time seeing the numbers on the screw shield maybe I have a wire in the wrong place. I have my valves wired and they all work. I have the boil HLT and rims set up for PID out put.Yesterday when I had one of the probes working I assigned it to the boil kettle, it looked like it should have been working but the SSR for the boil never flickered. I did have all my probes working one at a time. Most of them are seven years old and the outer insulation is bad. I'm going to order new ones just to make sure all is good.

Thank  Tom

Thanks Tom

BD I had bad resister wired in changed it for a new one and sensors now work.The PID problem was user error. they now work.My pressure sensors are next, I have them in the HLT and boil kettle. The boil ket is showing a reading of  0, on BruControl the output pin from the sensor shows .082 volts. The sensor the HLT is showing 277 on BruControl the output pin on sensor shows .615 volts  can you show me how to calibrate to gallons.  

Tom

Hi Tom,

Glad to hear! If you don't mind the delay, I will do a whole write-up tonight on how to do the pressure sensor setup including calibration, with a spreadsheet.

But at a high level, you will put in a linear offset first to set the actual volume when the water just makes the sensor start to register. Then a linear multiplier to convert the voltage change per pressure change multiplied by the volume per height (depends on the diameter). 

BD You don't need to do it tonight, I  probably will not be able to do any thing for a couple of days.

thanks  Tom 

Hi Tom,

I posted a spreadsheet you can use to perform the calibration. It is here: http://brucontrol.com/build/resources/

Let me know if you need any help!

Thanks for posting the spreadsheet I would never have been able to calibrate with out it. It took 7 fills to get it right. My boil kettle sensor has quit working, so I didn't have to calibrate it. Will do without it for now.My next step will be to have BruControl to fill the HLT with RO water and have it to shut off at the volume I need some time be fore brew day.

 Tom