Remote temp sensing help??

Hi people,

I live on a small acreage and I have two wells and two pump rooms on
the property. Winter temps frequently get below freezing so I have to
keep a small heater in them to prevent pipes freezing overnight.

Currently I use some cheap indoor/outdoor thermometers to monitor the
temp inside the insulated enclosures but I have to walk to each one to
check it.

I need some temp senders so I can have a remote station in the house
and each one can constantly indicate the inside temp so if the heater
dies I can get down there and fix it. I can have a switch to cycle
through them manually I do not need a 4-station setup but that would
be a nice luxury, cost permitting.

There is 110v in all places so batteries are not an issue. Can anyone
suggest a CHEAP kit I can get? The farthest away sender would be about
800 feet.

Thanks in advance.


--

Kind regards,
Jenny and her tribe of survivors.

 

[Scott Miller]

I need some temp senders so I can have a remote station in the house
and each one can constantly indicate the inside temp so if the heater
dies I can get down there and fix it. I can have a switch to cycle
through them manually I do not need a 4-station setup but that would
be a nice luxury, cost permitting.

There is 110v in all places so batteries are not an issue. Can anyone
suggest a CHEAP kit I can get? The farthest away sender would be about
800 feet.

This is probably overkill for your application, but I sell a kit of my own
design that can do that...

http://n1vg.net/opentracker

It's really intended to be used over amateur radio, but if you don't have a
license you could probably use it with a radio on one of the nonlicensed
bands. MURS, maybe - I'm pretty sure telemetry is forbidden on FRS and
GMRS.

I've got a number of users using these for temperature and voltage
monitoring on remote mountaintop repeater sites. The cool part is that if
you do have a ham license (easy enough to get), you can use an existing
nationwide APRS network on 144.39 MHz that'll get your data onto the web.
And because I've got so many people using these things for enviromental
monitoring (I originally designed them for GPS-based vehicle tracking) I'm
working on developing an email notification system, so you could be notified
when the temperature crosses a defined threshold. That's assuming you're on
the APRS network - standalone, you'd have to run a receiving station
yourself.

Yeah, at 800 feet you're probably better off using off-the-shelf home
automation stuff. But for ranges of many miles, this is a pretty slick (and
cheap) solution.

Scott

 

[Rich Grise]

On Sun, 09 Jan 2005 13:26:41 -0700, Jenny3kids wrote:

Hi people,

I live on a small acreage and I have two wells and two pump rooms on
the property. Winter temps frequently get below freezing so I have to
keep a small heater in them to prevent pipes freezing overnight.

Hi person. ;-)

My recommendation, as a Technical Consultant, is to listen to one (or
more) of those folks who knows more about that area of expertise than I
do! ;-)

(IOW, I wouldn't want to take on an 800-foot wireless project or string
an 800-foot wire, personally.)

But please, do keep us posted!

Good Luck!
Rich

 

[Jonathan Kirwan]

On Sun, 9 Jan 2005 18:13:33 -0800, "Scott Miller" <scott@3xf.com> wrote:

Scott your solution does seem a little more than I have in mind, but
thanks for the suggestion.

I don't think you specified in the original post if this needed to be a
wireless solution or not. If you don't mind running wires, you might be
able to get away with a Dallas 1-wire bus. 800 feet is a lot of wire (and
possibly a lot of trenching) though - but the sensors are cheap, and you
only need two conductors.

Most of the wireless stuff I deal with is either short range (e.g., ZigBee,
keychain remotes) or long range (many miles), not much in between. FCC
rules aside, if I was doing this I'd probably hook a couple of my kits up to
cheap Walmart FRS radios, with a third back at the house connected to a
soundcard on a PC running a software modem program. The temperature sensors
are built in, so no extra hardware there. Definitely helps to have a spare
PC and soundcard available, though. There's hardware that'll do the
decoding without a PC, but that'd probably go over your $100 budget.

This has all been very interesting for me to read. Jenny, thanks!

My own situation is quite similar to Jenny's. I also have a pumphouse, for
example, that is also on a separate power meter *and* a separate transformer
system, as well. My own pumphouse is approximately 1200 feet away, as well as
downhill from the main house by about 150 feet (so I have about 75 PSI
difference between the pumphouse pressure and house pressure.)

There is wiring between them, for pump control relative to the storage tank
pressure at the house, but it's a buried line (sadly, it appears that at least
some of it is buried without any conduit, as well -- I've seen it near the
house.) Trenching for new wiring would be ... very expensive. And there is no
existing set of poles for mounting above ground wiring.

There *might* be a line-of-sight possibility between the house and the
pumphouse, but there are many fir trees as well as maple, birch, and ash in
between, so providing a clear path in winter and summer might be tricky.

I do *not* have a HAM license.

Data rates could be very low and high error rates could be tolerated, as long as
command/status updates of once per 10 minutes or so could occur in each
direction.

Bidirectional laser communication would be an idea, assuming I can find a
suitable optical path (maybe) -- I'd consider using a 4X gunscope for the
receiving end of each side, I suppose, with a detector placed appropriately.
And an adequately powerful and appropriately aimed laser emitter. But it would
still need to operate in broad daylight or even in the not-infrequent heavy snow
and ice environment in the winter. Optical filtering as well as tight control
of modulation with a narrow band receiver as used in street light controls might
be appropriate. But it starts getting pretty tough for something reliable, I
think.

An RF arrangement would be simpler in ways, but it would require a sufficient
transmitter/receiver combination. And for that distance, I imagine that
operating on a single wavelength would probably violate FCC regs. one of the
several (two, I think) non-military spread spectrum techniques might be an
option, but I'm not sure. It's possible that accepting very high bit error
rates through the use of encoding and decoding protocols may permit legal use of
a single prime frequency.

Sounds like the FRS two-way radio idea is worth considering for this, though.
I've already checked out a pair and they work excellently for voice over this
distance. I'll start looking into that further, now. If there are some other
interesting thoughts about it... I'd be interested in those, too.

Jon

 

[Terry Pinnell]

Jenny3kids@msn.net wrote:

Hi people,

I live on a small acreage and I have two wells and two pump rooms on
the property. Winter temps frequently get below freezing so I have to
keep a small heater in them to prevent pipes freezing overnight.

Currently I use some cheap indoor/outdoor thermometers to monitor the
temp inside the insulated enclosures but I have to walk to each one to
check it.

I need some temp senders so I can have a remote station in the house
and each one can constantly indicate the inside temp so if the heater
dies I can get down there and fix it. I can have a switch to cycle
through them manually I do not need a 4-station setup but that would
be a nice luxury, cost permitting.

There is 110v in all places so batteries are not an issue. Can anyone
suggest a CHEAP kit I can get? The farthest away sender would be about
800 feet.

Thanks in advance.

I've had X10 on my list of Things To Try for about 10 years, so I
still have no practical know how. But, like JP, I'd have thought that
a sound approach too for this spec. Potentially compelling advantage
that all the mains wiring is already in place. Has your experience
with it really been that bad?

But, excluding that, for reliability and cheapness I think I'd favour
the hard-wired approach. The wire itself will be the most expensive
outlay. Despite needing to carry only a low current signal, the cable
diameter will probably need to be fairly substantial for robustness.
(My garden lamp relay box is probably only 100' from the shed-based
control circuit, running along a fence behind flower borders, but the
original thin wire I used proved inadequate against careless hedge
cutting and rose pruning.) The cable would link JF's temperature
detecting circuit to your house LEDs and piezo.

BTW, for further simplicity (and cost reduction), wouldn't it be
possible to use just *one* sensor? If the general temperature is close
to danger level, then I'd have thought all four sites would be close
to their 'risk thresholds' ?

If the distance had been much less I'd have gone for adapting a
wireless door-bell. I've used that successfully for several projects.
But I suspect a radio-based approach for reliable 800' operation would
be rather expensive.

I don't suppose you can *see* all 4 sites from the house? If so (and
if other factors like neighbours don't rule it right out) I wonder if
it might be possible to use a mains-operated lamp at each of the four
sites. If necessary, with an additional appropriately-positioned
mirror or two. And, again subject to the neighbour proviso (and your
willingness to sleep with a window ajar in winter), maybe a loud but
cheap piezo at each location, or shared if some of them are close?

Hmm ... on reflection, and thinking about safely routing all that
wire, radio begins to look attractive <g>. I think I'd look at a cheap
R/C model kit (plane or helicopter, for the range). Adapting one for
simple on/off switching could be fairly simple. Fun too.

--
Terry Pinnell
Hobbyist, West Sussex, UK

 

[Rodney Josey]

On Mon, 10 Jan 2005 20:13:03 +1000, Rodney Josey <rjosDIESPAM@dodo.com.au> wrote:

On Sun, 09 Jan 2005 13:26:41 -0700, Jenny3kids@msn.net wrote:

Hi people,

I live on a small acreage and I have two wells and two pump rooms on
the property. Winter temps frequently get below freezing so I have to
keep a small heater in them to prevent pipes freezing overnight.

Currently I use some cheap indoor/outdoor thermometers to monitor the
temp inside the insulated enclosures but I have to walk to each one to
check it.

I need some temp senders so I can have a remote station in the house
and each one can constantly indicate the inside temp so if the heater
dies I can get down there and fix it. I can have a switch to cycle
through them manually I do not need a 4-station setup but that would
be a nice luxury, cost permitting.

There is 110v in all places so batteries are not an issue. Can anyone
suggest a CHEAP kit I can get? The farthest away sender would be about
800 feet.

Thanks in advance.

Hi Jenny,

Here in OZ back in July 2003 (would you believe it is now Jan 2005) - our local electronics magazine
- SILICON CHIP - featured an article on using an PICAXE chip for communications purposes AND even
had a small section referring to 'wireless' linking using prebuilt hybrid 433MHZ UHF radio modules
at each end - reasonably cheap & developed for licence-free radio links. Now with a simple
directional RF antenna it is suggested that such links could reach up to a few kilometers.

If you think this type of circuit arrangement may be useful, you might want to look at getting a kit
from one of our local suppliers - www.oatleyelectronics.com - they can supply both the RF modules as
well as the Picaxe chips - if you need any additional 'interface' circuitry then let me know and
I'll see what I can draw up for you.

Oz-Rod

BTW: I forgot to mention that the PICAXE range of chips can do reasonably well at reading
temperature from various sensors (part of the in-system program).

Oz-Rod

 

On Sun, 09 Jan 2005 23:58:30 -0500, John Popelish <jpopelish@rica.net>
wrote:

OK, thanks guys, too many to answer individually so will try and
remember all suggestions.

If both meters run off the same pole (or buried) distribution
transformer, they should.

I think so, there is a can at the top of the main pole into the
property so maybe the X10 is worth a try. My bitch with X10 was when
using them to control lights in the house. The controller would
occasionally scramble it's brains and I have to fire up the software
and reset all the start/stop times. A real pain in the arse. The other
thing was that the wall outlets use relays and when they switch on/off
there is a hellasious clunk. I had assumed they would use solid sate
relays. DOH! Just as you are dozing off to sleep the X10 turns off the
lights somewhere, bingo wide awake again. POS!

OK, back to the issue. I think I see a woman walking the rounds
looking at the temp meters. <g> Although someone suggested a light I
can see from the house. That might be a good alternative, I can't see
one wellhead but I can run a 30' wire to the pump shed for it's light.
As to sleeping with a window open in Winter, who ever suggested that
obviously lives in Florida. LOL. With 12 deg nights, it's hard enough
to stay warm as it is. <g>

I had thought of the R/C thing and actually have a 2-channel here
somewhere. However given the obvious complexities involved with most
of the suggestions, I think I will thank you all very much for your
help and head out the door to read my meters.

It seemed like a good idea at the time, but it is just getting too
complicated compared to a 5 minute walk. The only thing I might do is
rig some sort of warning siren and screw the neighbors. Just kidding
they wouldn't hear it.

Thank you very much to all of you for trying to help.


--

Kind regards,
Jenny and her tribe of survivors.

 

[Michael]

Jenny3kids@msn.net wrote:

Hi people,

I live on a small acreage and I have two wells and two pump rooms on
the property. Winter temps frequently get below freezing so I have to
keep a small heater in them to prevent pipes freezing overnight.

Currently I use some cheap indoor/outdoor thermometers to monitor the
temp inside the insulated enclosures but I have to walk to each one to
check it.

I need some temp senders so I can have a remote station in the house
and each one can constantly indicate the inside temp so if the heater
dies I can get down there and fix it. I can have a switch to cycle
through them manually I do not need a 4-station setup but that would
be a nice luxury, cost permitting.

There is 110v in all places so batteries are not an issue. Can anyone
suggest a CHEAP kit I can get? The farthest away sender would be about
800 feet.

Thanks in advance.

--

Kind regards,
Jenny and her tribe of survivors.

An issue of Circuit Cellar several years ago had an article on an
X-10-based system for something similar to what you need. The author
wanted to turn a fan ON/OFF in his kid's 2nd- or 3rd-story bedroom,
depending on temperature. PIC-based trnasmitter queried upstairs
receiver for temperature via X-10 (TW-523?). Receiver measured temp.,
sent back either a HIGH or LOW signal. Transmitter could then either
ignore the situation altogether or send an ON or OFF command to the
fan's X-10 appliance module.

I was on the verge of building the thing when my need evaporated. If
you'd be interested, I'll look up the article.

By the way, I agree than some X-10 stuff is junk. But for the past 15+
years I've used the simple desktop manual X-10 controllers, the bedside
table clock/controller, and lamp modules to great advantage. If I had
to get out of my TV chair to make a light brighter or dimmer I wouldn't
know how to act. And the last time I turned OFF the downstairs lights
*before* going upstairs to be was in the late 1980's.

 

On Mon, 10 Jan 2005 13:10:25 GMT, Michael <NoSpam@att.net> wrote:

Thanks Michael,

I was on the verge of building the thing when my need evaporated. If
you'd be interested, I'll look up the article.

I think I will stick with the walk and the temp meters for the time
being. It isn't as simple as I suspected or hoped it might be.

I agree on some of the X10 stuff, but it drove me nuts about every 3
weeks the lights would start coming on in the middle of the night or
day, or stay on all the time.

I called them and they said spend more money on their filters. I
figured I had thrown enough good money after bad so put up with
resetting them for about 12 months then tore out all the outlets and
went back $3 timers from walmart. Not quite as hitech but they work
and still are 3 years later. The timers don't have that loud relay
CLUNK either. KISS in place now, and I suspect that's the best idea
for my wellheads and pump rooms too. <sigh>

Thanks anyway


--

Kind regards,
Jenny and her tribe of survivors.

 

[John Fields]

On Sun, 09 Jan 2005 17:46:30 -0700, Jenny3kids@msn.net wrote:

John Fields, your solution sounds fine to me. I can toss a solder iron
around and can build from your schematic. I would very much appreciate
that. I am happy with red/green LED's. In fact I'll probably add a
piezo with the red LED. Someone might need to get down there in the
middle of the night. Bbbrbrrrrrrrr. <g

Thel lowest I have seen the wellhead is 38 deg F, so I'd want it to
trigger the red LED at 40. That way if it does hit 38, I can scoot
down and make sure the bulb is still OK.

How involved would be setting up the transmitter and receiver
frequencies after building? I have a a'scope but no signal generator.
Could I buy a Tx/Rx set and just add your stuff? Say Vellerman/Ramsey
or something? As to "cheap" probably $100 or less. Not wishing to
whine, but single mom, couple of kids, so a walk around looking at
harbor freight temp meters needs a lot of justifying to spend more
than that.

---
You could make the thing wireless if you wanted to, but I seem to
recall that you said in another post that you have wiring available to
all four locations. Is that the AC mains wiring or do you have
something like an extra pair of wires going to each location? If you
do, that would make it far more robust, easier to set up, cheaper,
etc.

Also, it would make it possible to power the temp sensors from the
house unit and eliminate the four power supplies in the pump rooms.

What I'm thinking of is something like four little boxes (senders)
with temp sensors and the necessary circuitry in them to trigger the
receiver alarm, a 2-terminal terminal block to connect them to the
wires going to the house, and a box (receiver) in the house with a
green POWER LED, 4 red and 4 green LEDs to indicate OK temp and
undertemp for each channel, a piezo sounder and a RESET pushbutton
switch to reset the sounder, and an 8-terminal terminal block to
connect the wires going to the senders.

The whole thing would be driven by a single (probably 12V) wall-wart
with a regulated output which would plug into the receiver and run
everything.

If you have that extra wiring, could you describe it? That is, its
construction (lamp cord, twisted pair, twisted shielded pair, coax,
???) and the diameter of the conductors (or the AWG)?

Also, do you get much lightning where you are and are there any radio
or TV stations close by?

--
John (a bicycle) Fields

 

[Fred Bloggs]

Jenny3kids@msn.net wrote:

Hi people,

I live on a small acreage and I have two wells and two pump rooms on
the property. Winter temps frequently get below freezing so I have to
keep a small heater in them to prevent pipes freezing overnight.

Currently I use some cheap indoor/outdoor thermometers to monitor the
temp inside the insulated enclosures but I have to walk to each one to
check it.

I need some temp senders so I can have a remote station in the house
and each one can constantly indicate the inside temp so if the heater
dies I can get down there and fix it. I can have a switch to cycle
through them manually I do not need a 4-station setup but that would
be a nice luxury, cost permitting.

There is 110v in all places so batteries are not an issue. Can anyone
suggest a CHEAP kit I can get? The farthest away sender would be about
800 feet.

Thanks in advance.


--

Kind regards,
Jenny and her tribe of survivors.

You should be using pipe heater tape and not a light bulb on that well
head. What is the layout of those pump houses- can you daisy chain a
path between them and back to the house? The simplest solution would be
to buy a 1000' spool of 4-wire direct burial telephone cable off the
surplus market for ~$50 - you can just string it out for now and wait
until spring to bury it. If burial is not feasible, then a UV resistant
type strung along a fence or whatever is another option. Then do a
4-20mA current loop transmission of the temperature.

 

[John Fields]

On Tue, 11 Jan 2005 10:57:41 +0000, Terry Pinnell
<terrypinDELETE@THESEdial.pipex.com> wrote:

You must have missed her follow-up
news:35t4u09a491cgiak98ki1v7r4siaagp586@4ax.com
in which she opted out of an electronics solution!

---
Yup. Oh, well...

--
John Fields

 

[bsting]

Hi, a new technology is out there that really can help this problem.
It involves meshing or linking multiple radios to each other to relay
the data. Here is link on how it works:

http://computer.howstuffworks.com/mote.htm

-Brian


Jenny3kids@msn.net wrote:

On Mon, 10 Jan 2005 13:10:25 GMT, Michael <NoSpam@att.net> wrote:

Thanks Michael,

I was on the verge of building the thing when my need evaporated.
If
you'd be interested, I'll look up the article.

I think I will stick with the walk and the temp meters for the time
being. It isn't as simple as I suspected or hoped it might be.

I agree on some of the X10 stuff, but it drove me nuts about every 3
weeks the lights would start coming on in the middle of the night or
day, or stay on all the time.

I called them and they said spend more money on their filters. I
figured I had thrown enough good money after bad so put up with
resetting them for about 12 months then tore out all the outlets and
went back $3 timers from walmart. Not quite as hitech but they work
and still are 3 years later. The timers don't have that loud relay
CLUNK either. KISS in place now, and I suspect that's the best idea
for my wellheads and pump rooms too. <sigh

Thanks anyway


--

Kind regards,
Jenny and her tribe of survivors.

 

[Clarence_A]

"bsting" <bsting_fun@yahoo.com> wrote in message
news:1107113420.952887.62920@f14g2000cwb.googlegroups.com...

Hi, a new technology is out there that really can help this
problem.
It involves meshing or linking multiple radios to each other to
relay
the data. Here is link on how it works:

http://computer.howstuffworks.com/mote.htm

-Brian

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