[TriEmbed] Question: On/Off Sensor for Hot Water Heater

Wed Jan 14 19:03:44 CST 2015

Yep, these are a little pricey but they look rugged – industrial. I’m putting them on my list as a back-up. I need to research all the info you gave me a little more. I really appreciate it. 

Thanks!

Dwight

From: TriEmbed [mailto:triembed-bounces at triembed.org] On Behalf Of Mark Sidell
Sent: Wednesday, January 14, 2015 4:17 PM
To: Triangle Embedded Devices
Subject: Re: [TriEmbed] Question: On/Off Sensor for Hot Water Heater

If money is not an issue, Veris sells on/off current sensors with digital outputs. (As others have noted, since a water heater is a constant load, on/off is all you need.) I used the H800 to monitor my water heater. I clamped it around one of the hots, in the electric panel. Be careful with that, of course!

    http://veris.com/product_results.aspx?keyword=H800

As an aside, I use a couple of Continental Control Systems WattNode Pulse units to measure power usage for the mains and heat pump. These devices output pulses at a rate proportional to power. 

   http://www.ccontrolsys.com/w/Home

I feed the pulses to a Hobby Boards 1-wire dual counter board, which a computer reads at regular intervals:

   http://www.hobby-boards.com/store/products.php?product=Dual-Counter

On Wed, Jan 14, 2015 at 3:12 PM, Rodney Radford <ncgadgetry at gmail.com> wrote:

Great board (current sensor) and a decent price ($18), so I will definitely add it to my list of future projects.

However, I was wondering if there wasn't a simpler way to do this - my hot water heater has a light that comes on whenever the heating coil is on, and goes off when the coil is off. That light is a neon light, so there is an almost zero chance it will not work.

It would be easy to add a light sensor over that light and sense it, and that may be a cheaper solution for you.

However, if the $18 is not too high, that option does give you the option of not only knowing it is on, but also measuring the wattage - a very nice plus.

On Wed, Jan 14, 2015 at 3:05 PM, Dwight Morgan <dwight.w.morgan at gmail.com> wrote:

Thanks Shane!

This is interesting. Right much of the article was a bit over my head right now but I can see this may be an option for me. I need to do a little more research on it – look at specs closer. I appreciate the info.

Dwight 

From: Shane Trent [mailto:shanedtrent at gmail.com] 
Sent: Wednesday, January 14, 2015 2:43 PM
To: Dwight Morgan
Cc: Triangle Embedded Computing Discussion
Subject: Re: [TriEmbed] Question: On/Off Sensor for Hot Water Heater

Dwight,

Here is pre-built board that might do what you want. It's a good read about using Hall Effect sensors for monitoring AC current.

http://moderndevice.com/new-products/current-sensor/

Shane

On Wed, Jan 14, 2015 at 2:15 PM, Dwight Morgan <dwight.w.morgan at gmail.com> wrote:

Hello All:

I want to monitor when my hot water heater is on and off using my Arduino UNO. I have done research on sensors and it looks like the best choice is the ACS712 Hall Effect Current Sensor. 

My water heater has two 4500 Watt elements at 240 Volts. So the calculated current draw is 18.75 amps since only one element is on at a time.

My question(s): First, is the Hall Effect sensor a good choice and second, if so, will the 20 amp rated one work okay? 

Also, if this is viable, I think I will try to use Cat5 cable to pick up the signal which will be about 100 feet away. I’m not sure exactly about the connectors yet.

All advice is appreciated. 

Thanks!

Dwight

_______________________________________________
Triangle, NC Embedded Computing mailing list
TriEmbed at triembed.org
http://mail.triembed.org/mailman/listinfo/triembed_triembed.org
TriEmbed web site: http://TriEmbed.org

_______________________________________________
Triangle, NC Embedded Computing mailing list
TriEmbed at triembed.org
http://mail.triembed.org/mailman/listinfo/triembed_triembed.org
TriEmbed web site: http://TriEmbed.org

_______________________________________________
Triangle, NC Embedded Computing mailing list
TriEmbed at triembed.org
http://mail.triembed.org/mailman/listinfo/triembed_triembed.org
TriEmbed web site: http://TriEmbed.org

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.triembed.org/pipermail/triembed_triembed.org/attachments/20150114/831ffc64/attachment.htm>