wpns
Solar Joules are catch and release
Also a water meter with contact closure (one pulse per gallon) running to a Raspberry Pi will tell you how much you are using per hour/day and have settable alarm limits.
Timed pump shutoff to prevent continuous running of well pump?
- Thread starter jimf909
- Start date
BAM! It finally clicked for me. I already have a 30/50 switch like this in my system and all I need to do is replace it with one with the low pressure cutoff. My brain was trying to think of how I'd add the switch to the system. $30 and a proven decades old tech. Win-win. Thanks.
Square-D Pressure Switch 40/60 with Low Pressure Shut-off
The industry standard for controlling electrically driven water pumps. Low Pressure Shut-Off operates at approximately 10 PSIG below cut-in and will turn off the pump.
aquascience.net
A low cut off pressure switch turns the pump off in the event that the water pressure in your lines drops lower than the cut-in pressure (low number). Imagine that there was a leak or break in your water line. This would cause the pressure in your line to drop and your pump to kick on and stay on which could lead to flooding of your home or business. The low cut off pressure switch would turn the pump off if the pressure drops 10 psi below the cut-in pressure (low number). Think of it as a nice piece of protection.
That's awesome. Simplest solution is usually best.BAM! It finally clicked for me. I already have a 30/50 switch like this in my system and all I need to do is replace it with one with the low pressure cutoff. My brain was trying to think of how I'd add the switch to the system. $30 and a proven decades old tech. Win-win. Thanks.
What does a Low Cut-Off Pressure Switch do?Square-D Pressure Switch 40/60 with Low Pressure Shut-off
The industry standard for controlling electrically driven water pumps. Low Pressure Shut-Off operates at approximately 10 PSIG below cut-in and will turn off the pump.
A low cut off pressure switch turns the pump off in the event that the water pressure in your lines drops lower than the cut-in pressure (low number). Imagine that there was a leak or break in your water line. This would cause the pressure in your line to drop and your pump to kick on and stay on which could lead to flooding of your home or business. The low cut off pressure switch would turn the pump off if the pressure drops 10 psi below the cut-in pressure (low number). Think of it as a nice piece of protection.
One thing to note- if the low pressure cut off is activated you have to go out to the pressure switch and manually flip the lever to switch it back on.
Is there a tutorial for this?
We have two wells going into 2 cisterns, when there's cattle in the summer both wells run 20 plus hours on a hot day especially when the house is occupied and continuous if a float is broke, This has been going on for 20 plus years. It could be helpful how deep your wells are and how big a pump, That said I would not worry about it, if the well is deep your back pressure won't dry out the pump as another person stated your pressure tank also keeps things lubricated. Only variable is how much sand, dirt going through the pump wearing out your propellers. IMOP cheers.
That's what I need. If something breaks there needs to be manual intervention to start the pump and fix the problem.
Thanks. I'm not concerned about the pump. My issue is that if the pump runs continuously it will drain the batteries creating a low voltage condition that will shut off power to the fridge, freezer, wifi network, etc. The loss of food is the biggest issue. Loss of communication is a moderate concern.
The generator is on AGS and will start automatically and that will eventually drain the 500 gallon propane tank, depending on how long I'm away. This $30 solution will prevent those problems.
Also, if the leak is in the house this will limit the water damage to 80 gallons or so.
wpns
Solar Joules are catch and release
Well, not exactly, but it's pretty straightforward, and there are lots of tutorials for setting up inputs. I use Python because that's the RPi ecosystem standard:
import RPi.GPIO as GPIO
GPIO.setmode(GPIO.BCM) # HCDC boards use BCM numbers
GPIO.setup(index, GPIO.IN) # , pull_up_down=GPIO.PUD_UP)
GPIO.add_event_detect(index,GPIO.BOTH,callback=Callback,bouncetime=BounceIgnore)
I use Redis for in-memory database, but you can use anything:
def Callback(channel):
time.sleep(BounceSettle/1000.0)
RedisDB.incr(<Name of counter>)
And then in another program (I fire this off every minute in crontab) transfer accumulator to SQL:
count = redisDB.getset(<Name of counter>,0) # reset it
SQLstring = 'insert into Counts(Epoch,Channel,EdgeCount) '
SQLstring += 'VALUES(unix_timestamp(now())'
SQLstring += ',{},{}'.format(channel,EdgeCount)
SQLstring += ');'
cursor.execute(SQLstring)
Then in Yet Another Program, get the last 24 hours of data from SQL:
sql = "select Epoch, EdgeCount "
sql+= "from Counts where Channel = {} ".format(Dict['Channel'])
sql+= "and Epoch >= (unix_timestamp(now())-(60*60*24)) "
sql+= "order by Epoch"
datacursor.execute(sql)
I use matplotlib for graphing, but there are lots of options out there, https://grafana.com/ seems to be all the rage, but old dog, new tricks, you know....
Does that help?
Pardon but you also said you need for the pump not to be cycled too long from someone running water excessively. The pressure switches that require reset from having pressure drop to nothing (broken pipe) will not handle that.
I don't understand what you're saying.
wpns
Solar Joules are catch and release
There are a bunch of different failure modes that the OP is trying to solve.
The dropout-on-low-pressure switch will solve some egregious issues (broken pipe, loss of input water, etc) but may not cover others (faucet left on, slow leak, neighbors using too much water).
I’ve got all kinds of sensors on my irrigation system, including cistern input and output gallon counters, back pressure sensor on ozone treatment system to know approximate storage volume, water pressure (and temperature) sensor to watch for leaks, pressure pump temperature sensor to shut down irrigation controller if water flow stops and pump overheats, and power consumption readings to confirm expected operation. It’s all belt-and-suspenders stuff, but it’s my hobby so I enjoy it.
For the OP the low-hanging fruit is the low-pressure-dropout switch. Everything else is risk/cost/value/reward. He could also look at battery SOC and disable the water at less than a certain point to preserve power for other uses, for instance.
That seems to be a problem I have. Read WPNS post.
That's correct. This is easily solves the problem of broken pipe, etc. which is my biggest concern. I'll continue looking at other monitoring solutions suggested for lesser leaks.
One other thing you may want to think about is exactly where to place this "shutoff switch". In my situation, the pressure tank is about 40 feet from where the pipe from the well enters my basement. If I place a switch after or at the pressure tank, any break or leak in the 40ft of piping before the tank will go unnoticed. The well pump will just keep running in that situation.
edit: This is assuming you want to install some sort of valve/switch to just stop the water flowing.
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wpns
Solar Joules are catch and release
Well, you should never have the switch that far from the pump, but the low-pressure-dropout switch will take care of a broken pipe.
I'm assuming the OP wants to remove power from the pump when "something goes wrong", there's no need for an electrically-operated water valve.
Steve_S
Offgrid Cabineer, N.E. Ontario, Canada
Sorry for not responding sooner.
With a 120V Well pump ou have a few options to go, some complicated while others are simple.
I have installed solar systems with 120V pumps in use and a few had similar requirements to ensure pumps would only run at certain time periods. In some cases other equipment as well needed to be time blocked. The simplest Good Working solution is to use a Programmable Timer for car Block Heaters (they handle higher wattages). Digital ones are better & have more options. Also there are now several Smart-Plugs which can be programmed via phone APP that are able to handle 120V/15A without issue.
I've installed "NOMA Outdoor Digital Timer, 20 Programmable settings, 2 Grounded Outlets" for a couple and even used a Samsung Smartplug (15A model) to handle a well pump. FYI - All SOFT-START !
Yes makes perfect sense.
efficientPV
Solar Addict
- Joined
- Sep 24, 2019
- Messages
- 1,372
All you need is an ON DELAY TIMER with a NC/NO relay contacts (or external relay). When pump is to be powered on, the delay timer starts. Power to the pump goes thru the NC contact. The delay starts and when it exceeds 30 minutes, the relay opens. It can be reset once the power to the timer and pump is removed.
