Not sure which PCB design you’re using, but my latest designs break out 5V on a separate pin for this purpose.
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I have some of your older boards (1-2 gen). The new boards will shift the cooling signal to 5v?
Sort of — The signal itself coming off the microcontroller needs to be 3v3, but the relay boards have optoisolators built in to allow the 3v3 signal to switch a 5v signal which then in turn switches the relays.
The latest PCB design just has a 5V and GND pin broken out to make this a tad bit easier.
This is what @day_trippr ’s schematic was referencing — the JD-VCC pin on the relay board can be hooked up to 5V (with the jumper removed!) and you will be driving the relay with 5V. If you have a convenient way to break out a 5V line to go to the relay board with your current PCB then you don’t need a new design - hook that up and you’re golden.
This is the relay I am hopefully going to use. I haven't found a clear schematic yet, but the jumper just says high, com, low, triggers. Don't know if their the same yet.
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I have no experience with that board, but it looks like it might have an optocoupler wedged in there between the blue relay and the green screw terminal (the chip that has “354” written on the top) so I would guess that the design is able to be triggered with voltage lower than 3v3 (and use higher voltage to then subsequently drive the relay). Not sure how you would hook it up though.
What are the labels for the green screw terminals?
Pos, neg, in1. Does have an optocoupler.
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I think I'm mistaken. This design uses the optocoupler in order to allow for both high and low-level triggering (hence the high/low with the jumper) -- not for allowing decoupling of the signal and the power to drive the relay itself.
You could still make this work by adding a level shifter somewhere, but it's going to be additional hardware beyond the basic PCB design.
Do you remember on you older pcbs w/shifter do they use all the channels?
The circuit provides 5V across the relay coils, using an opto-coupled input sufficient to respond to 3.3V signalling levels. By noting the respective voltages I assumed you would follow the rails and arrive at the above conclusion. And if you don't want the optocoupler, drive the resistor at the base of the 2222 with the 3.3V control.
The relay pictured almost certainly uses the circuit I provided, btw. You can see the optocoupler and a 3 pin sot that's surely a transistor of some type. Judging by the trace sizes going through the three pin header, I bet that picks from the NO and NC relay pins and not actually changing the relay behavior...
Cheers!
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rkhanso
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wouldn't something simple like this do the job?
or
or
Nope.
I provided the correct circuit above.
Understand completely, or copy faithfully...
Cheers!
I provided the correct circuit above.
Understand completely, or copy faithfully...
Cheers!
Would this be as simple as jumping d5 to the lv side and the hv pin out to the relay? Or is more hardware needed?
So your saying if I remove the jumper and jump 5v supply to the high pin it should switch properly? With the jumper removed, I already have 5v on the high pin?
This is what I'm saying: the jumper on that relay module may select which relay point to use, which is analogous to inverting the control response without the complexity...
To know for sure would require an ohmmeter...
Cheers!
To know for sure would require an ohmmeter...
Cheers!
Finally attempting my first dry run with Fermentrack, I tried to set up v0.14 serial and had a 66.8 degree offset on the beer temp probe (was reading 3.2 F) that I could not adjust for (wouldn't allow any value).
I also tried the v0.14 Low Delay, but as it is Wi-Fi only and for some reason the communication between the Pi and the Wemos fails every time it tries to update the controller.
I am back to the v0.11 serial and it appears to be working fine.
I am using a Glycol Chiller for my set up and I found that if I have the Chamber temp probe in the glycol(34 F) the SW thinks the "fridge" is too cold so it will not start the cooling cycle (pump in the glycol to the cooling coil in the conical).
I Have the beer temp probe in the thermowell, and the chamber temp probe slipped in between the conical and the neoprene insulating jacket, which the SW liked.
Will see how everything goes over the next couple of days.
I also tried the v0.14 Low Delay, but as it is Wi-Fi only and for some reason the communication between the Pi and the Wemos fails every time it tries to update the controller.
I am back to the v0.11 serial and it appears to be working fine.
I am using a Glycol Chiller for my set up and I found that if I have the Chamber temp probe in the glycol(34 F) the SW thinks the "fridge" is too cold so it will not start the cooling cycle (pump in the glycol to the cooling coil in the conical).
I Have the beer temp probe in the thermowell, and the chamber temp probe slipped in between the conical and the neoprene insulating jacket, which the SW liked.
Will see how everything goes over the next couple of days.
I actually think that this is the schematic for that relay board:
The jumper doesn't seem to select which relay point to use -- both are broken out -- it actually inverts the signal going to the relay.
The P3 header clearly allows selecting between using the NC or NO points.
Haven't figured out the other headers can change "polarity" vs the gpio input...
Cheers!
Haven't figured out the other headers can change "polarity" vs the gpio input...
Cheers!
It appears Thorrak has the correct diagram for this relay. Dc+ directly feeds low jumper and dc- feeds the high jumper pin, the com pin also goes through a 1k resistor to the opto
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This seems pretty solid so far. Relay switches on and off promptly.
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Glad to hear it!
Lalo_uy
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That diagram is wrong. The colector of the opto is Not conected.
And the relay coil is only connected to heather pin3
Hey all, I'm hoping someone can point out what is probably an obvious error I'm making in my ESP8266 Brewpi build. I can't get Fermentrack to recognize any of my DS18B20 probes when mocked up on thorrak's latest "main" and "sensor breakout" PCBs.
It works fine when I just put the 8266 (and even an ESP32-S2 mini) on a breadboard and wire the sensors directly to the ESP using the same power supply. The only measurable difference I can see is that I get ~4.6V at the probe Data pin when wired to the breadboard and only 3.3V when wired to the PCBs (the jumper on the main board is using 5v to power the probes, confirmed with a multimeter).
I'm using a LoLin D1 Mini supplied by thorrak (and a Hiletgo ESP32-S2 mini from Amazon, just to see), probes and power supply from a working Arduino BrewPi build. Im using the docker version of Fermentrack and tried v0.11 and v0.14 firmware on the boards.
Long-time lurker, and very grateful for all the work you guys do!
It works fine when I just put the 8266 (and even an ESP32-S2 mini) on a breadboard and wire the sensors directly to the ESP using the same power supply. The only measurable difference I can see is that I get ~4.6V at the probe Data pin when wired to the breadboard and only 3.3V when wired to the PCBs (the jumper on the main board is using 5v to power the probes, confirmed with a multimeter).
I'm using a LoLin D1 Mini supplied by thorrak (and a Hiletgo ESP32-S2 mini from Amazon, just to see), probes and power supply from a working Arduino BrewPi build. Im using the docker version of Fermentrack and tried v0.11 and v0.14 firmware on the boards.
Long-time lurker, and very grateful for all the work you guys do!
Is your Ethernet cable straight through or crossover?
To tell, take a look at the end of the cable and compare the colors of the wires. Should be the same colors in the same order on both ends.
It's a straight-through patch cable right out of the package. Also tried a different cable...same result. I checked continuity between the sensor board pins and the proper ESP pins. Also, there's no continuity on pins that shouldn't have it, so I'm reasonably confident it's not a botched solder job.
Do you have the jumper on the main board selecting the 5v or 3.3v setting? I seem to remember it not finding the sensors if nothing is selected.
I see you have the jumper on the main board sorry. I gave up of the surface mounted boards due to my limited skills and eyesight but it seems like a similar issue I had with no jumper in place.
I could be off and just guessing but are you meant to have resistors in this area?? It looks like an area for one of the small resistors to be soldered?
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What happens if you switch the jumper to 3.3v?
Pull-ups should be 2k2 for 3v3 and 4k7 for 5v0.
That's an optional solder bridge location if you want to permanently choose a voltage. I'd guess that 90% of builds won't use it, but it was free to add.
The whole reason the selector exists is due to an issue I had with a build once where I had sensors that worked fine with 3v3 but not with 5v. Step one for debugging this symptom is doing exactly what you mentioned and checking to make sure that at least one voltage is selected. Step two is to then check the other voltage.
Step three is to go cry in a corner because these things are almost all knock-offs at this point with minimal quality control...
True, but you can get away with 4k7 for 3v3 with most sensors.
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