I should be grateful for some help with my BruControl Setup for fermenting please.
I am using an Arduino Mega, 2 x PT100 with Adafruit Max31865 shields, and standard 6 x Arduino type relay board, and the issue is that during my first trial run.
Everything is stable when idling, as well as when cooling is called for, but when the heat is activated my temperature sensor / reading then goes haywire (generally in the minus range) for about 10 to 30 seconds or so (see photo) before it re-stabilises.
The situation appears to be an issue that just happens on the FV1 side, as the FV2 side appears stable.
Therefore, I should be grateful for your thought on what could be the issue with my system please? Thanks.
Is the heat source common for both FV1 and FV2 or individual ? If individual maybe try swapping them both (heat sources) and see if the problem changes with the exchange.
Do you have good separation of wires/cables between your relay and PT100 filter, I'm wondering if this is an EMI issue? When heating is called for it may be causing a spike which translates over to one of your PT cables/leads thus causing the negative reading.
Hi Tartan1, Thanks for your prompt reply, and although there is some separation between the wires, but you could be right with an EMI issue. I will look at move the MAX31865’ away from some nearby cabling. Thanks again.
Hi, Yes, I believe that it is an EMI issue, especially when a 12volt coiled relay triggers a 240 volt appliance, such as heater and the 240v external glycol pump.
Doing my monthly backuo to dropbox. If you do NOT have a good backup plan, you will not be happy one day. There is an automated backup in BruControl ( to your local drive) which is great, but one day that might not be enough!
I'm switching to a proportional SSR -- specifically the Crydom PMP2425w. Can I run this with 5v PWM (not duty cycle) alone? Or should I convert the signal to an analog 0-5v in front of the PSSR?
^definitely^ needs an "analog" transfer control input which can take many forms: 0-5 VDC, 0-12 VDC, 4-20ma (<- that one takes me back about five decades ). Not a pulse width control thing...