Btw did we ever find a reputable source for pre-made sensor probes, seems like the latest batches to hit the web have all been counterfeits or parasitic models
I bought some from ebay a few months ago and found out last week that none of them work at all. I just got 5 from Amazon a few days ago and all 5 are working well.
Vktech DS18b20 Waterproof Temperature Sensors Temperature Transmitter (5pcs) https://www.amazon.com/dp/B00CHEZ250/?tag=skimlinks_replacement-20
I use half a Sainsmart to control my keezer, with the little relay switching a 12V DC current loop that in turn switches a big honkin' 30A relay that powers the compressor.
The other half of the relay module controls a 12V DC cooling fan for the controller enclosure. Both sides work perfectly.
Can't answer the thermowell thing, never used one...
Cheers!
#!/usr/bin/env python
import RPi.GPIO as GPIO
import time
import os
import sys
cmd = '/opt/vc/bin/vcgencmd measure_temp'
GPIO.setmode(GPIO.BCM)
Fan_Control = 24
GPIO.setup(Fan_Control, GPIO.OUT)
TempOn = 130
TempOff = 110
FanOn = False
GPIO.output(Fan_Control,True) #! Note inverted logic, relay is now inactive
try:
while True:
line = os.popen(cmd).readline().strip()
if "error" in line:
print "Error ... is your firmware up-to-date? Run rpi-update"
else:
# line now contains something like: temp=41.2'C
# to get the temperature, split on =, and then on '
tempstring_c = line.split('=')[1].split("'")[0]
tempvalue_c=float(tempstring_c)
tempvalue_f = tempvalue_c * 9.0 / 5.0 + 32.0
tempvalue = round(tempvalue_f,1)
#! print tempvalue, "Degrees F"
if FanOn == False and tempvalue > TempOn:
#! print "Fan On"
GPIO.output(Fan_Control,False) #! Note inverted logic, relay is now active
FanOn = True
else:
if FanOn == True and tempvalue < TempOff:
#! print "Fan Off"
GPIO.output(Fan_Control,True) #! Note inverted logic, relay is now inactive
FanOn = False
time.sleep(10)
except KeyboardInterrupt:
#! print " Quit"
GPIO.cleanup()
#!/bin/sh
### BEGIN INIT INFO
# Provides: BrewPints RPi Temperature Monitor and System Fan Control
# Required-Start: $remote_fs $syslog
# Required-Stop: $remote_fs $syslog
# Default-Start: 2 3 4 5
# Default-Stop: 0 1 6
# Short-Description: Put a short description of the service here
# Description: Put a long description of the service here
### END INIT INFO
# Change the next 3 lines to suit where you install your script and what you want to call it
DIR=/usr/lib/cgi-bin
DAEMON=$DIR/fan_monitor.py
DAEMON_NAME=RPFanMon
# This next line determines what user the script runs as.
# Root generally not recommended but necessary if you are using the Raspberry Pi GPIO from Python.
DAEMON_USER=root
# The process ID of the script when it runs is stored here:
PIDFILE=/var/run/$DAEMON_NAME.pid
. /lib/lsb/init-functions
do_start () {
log_daemon_msg "Starting system $DAEMON_NAME daemon"
start-stop-daemon --start --background --pidfile $PIDFILE --make-pidfile --user $DAEMON_USER --chuid $DAEMON_USER --startas $DAEMON
log_end_msg $?
}
do_stop () {
log_daemon_msg "Stopping system $DAEMON_NAME daemon"
start-stop-daemon --stop --pidfile $PIDFILE --retry 10
log_end_msg $?
}
case "$1" in
start|stop)
do_${1}
;;
restart|reload|force-reload)
do_stop
do_start
;;
status)
status_of_proc "$DAEMON_NAME" "$DAEMON" && exit 0 || exit $?
;;
*)
echo "Usage: /etc/init.d/$DAEMON_NAME {start|stop|restart|status}"
exit 1
;;
esac
exit 0
sudo update-rc.d fanmon defaults
I wrote a small service in Python that reads the RPi2 SOC thermal sensor, converts it to Fahrenheit (just because), compares the sensor reading to an upper threshold and if the former exceeds the latter runs the fan until the sensor reaches the low threshold.
Here's the code for the service
Cheers!
I love it. My keezer is in a Southern California garage that gets to 110f during the summer. I'm going to incorporate this before the temps start rising this year. I'm on my original RPI and it hasn't died yet due to the heat, but I figure it is only a matter of time.
Might be ok in a fridge, but not in a keezer.
Too much condensation going on for that...
Cheers!
I bought some from ebay a few months ago and found out last week that none of them work at all. I just got 5 from Amazon a few days ago and all 5 are working well.
Vktech DS18b20 Waterproof Temperature Sensors Temperature Transmitter (5pcs) https://www.amazon.com/dp/B00CHEZ250/?tag=skimlinks_replacement-20
[...]About the sensor length, I foolishly bought the 100cm probes. Could I solder it together with some cable from home Depot without issue?
Might be ok in a fridge, but not in a keezer.
Too much condensation going on for that...
Cheers!
BTW I booted up the controller last night so I could figure out the wiring issue with the sensors and they showed up this time. I'm not sure as to why, but I'll take the win.
About the sensor length, I foolishly bought the 100cm probes. Could I solder it together with some cable from home Depot without issue?
Kinda. The box was bought then modified, the panel is custom, carved out of a piece of an aluminum speed limit sign one of my sons liberated about 20 years ago
Cheers!
Yes, you can just extend the probes with cable from Home Depot. Remember that the wires from all of your probes need to be wired together at some point in your setup anyway, so you could just hook up all of your 1 meter probes together and then extend the length with one cable to your needed length, if that works for your setup. If my explanation doesn't make sense, let me know.
Wait, so the ground, data and vcc would be connected to one wire? That wouldn't be problematic?
I get the idea behind the one wire in terms of the data line, but I'm confused how you could mix all three and still have a sensor.
And as I rarely build just one of anything, I built its twin in parallel, so the filing was doubled.
these are the ones I got, no issues whatsoever
except they're a little short, I should have gone with 2m
buzzbuzz... that's on me
Speaking of your builds, what Hammond box are you using on yer minions?[...]
Hi All,
First time poster here so pls be gentle. I have gone down the path of a DIY Brewpi but having issues with getting it up and running. Is there a good place to go trawling through to trouble shoot 'Script not running'? something for 'dummies' would be a great help!
What type of UNO R3 are you using? Ch340g chipset (Chinese clone)Hi All,
First time poster here so pls be gentle. I have gone down the path of a DIY Brewpi but having issues with getting it up and running. Is there a good place to go trawling through to trouble shoot 'Script not running'? something for 'dummies' would be a great help!
Cheers
Thor
Hi All,
First time poster here so pls be gentle. I have gone down the path of a DIY Brewpi but having issues with getting it up and running. Is there a good place to go trawling through to trouble shoot 'Script not running'? something for 'dummies' would be a great help!
Cheers
Thor
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