Heatedroofsystems

heated roofs automation

status

5/25/16

got What I now need from you

1/22/16

One way to design something is by implementing user stories. I have built what I need to implement most of the user story below. The little esp8266 wifi chip turns out to be awesome. It is up and running in a prototype. It reports on the state of the (my fake) HOA switch and if the HOA is in 'A'utomatic then it tells if it is automatic/on or automatic/off. It sends this information out to a server in the cloud whenever anything changes. At the same time, the microcontroller is listening for any changes that might be initiated by a user. 'Users' can read the status of the device on laptop or mobile device and can switch the (virtual) heater on and off. Observers can check the status without being able to change it.

Next thing I will probably do is work on the the 1 one feature of this story yet to be implemented

A form comes up asking for the ssid & passwd, and the device ID from the side of the box. Once entered, the mctrller resets and joins the home wifi network.

That gets me as far as I can get without real stuff.

What I now need from you

Send me a piece of your heater and a Veris model 103 SPST pilot relay with digital HOA monitoring and a Veris model V320-20A DPDT Relay (don't be concerned that is says 120V, it switches 2 120V poles at once.) Also a GFE could be for Cuttler Hammer or SquareD QC. I have both panels.Send this stuff to 12 Parley Vale, Jamaica Plain, MA 02130.

What is next for me

I have ordered the production wifi device plus the low voltage relays and connectors and boards I need for a more realistic prototype. Once I get your shipment I can select the best off the shelf circuit boxes for the setup, grab a 24v transformer and build the thing. I will spend a little bit more time on cleaning up the prototype controller/cloud/device communication software and maybe do a little work on the client devices. Then I will await the arrival of the stuff. Then I will test it locally and put the software in the cloud so you can control it.

to do(after that)

• build real clients with modern web technologies
• add server side authentication with different privileges for admin/installer/superuser/user/observer
• build server database for - HOA state over time for each registered device including who changed it and when (admin/user/weater...)
• build server side weather monitoring system.
• add client side weather info direct from external API
• add client side weather connection to server control

before 1/22/16

user story so far

The installer opens a box with a wifi enabled controller and the relays and power supply needed to control this IOT application of weather condition controlled ice-dam heaters.

The electrican has already been there, hanging a box on the panel, connecting the 220V roof panels through a 220 volt relay that is switched by a 110V pilot relay. The electrician has added a 220v breaker and a 110v breaker to the panel(or added to an existing 110V circuit). the 110v circuit powers the pilot relay, the 24 volt transformer and a 110v receptacle. The system now runs manually using the HOA switch on the pilot relay. He leaves a 100v receptacle and a low voltage connection block with 5 terminals: two of the terminals are the relay and the other 3 are the HOA digital monitoring signals.

The easisest thing would be a little circuit box with a 5 wire connector between what the electrican left and the microcontroller. Hook it up, plug in the usb power and find it on your laptop from its broadcasting AP. A form comes up asking for the ssid & passwd, and the device ID from the side of the box. Once entered, the mctrller resets and joins the home wifi network.

Now the installer goes online to check if the device is operating by going to a special page that references the deviceid. If he sees the status and can change it he is done.

intro

The first question that came to mind for this project was to be sure that there was a UL approved product that we could connect the control microcontroller to. There are a number of options. This one is the most flexible. Ii mounts to the panel of any junction box. It has a HOA switch (Hand control on, Off , or Automatic) that allows you override the automatic system and turn the heaters off and on from the relay if the internet or wifi go off.

Right now the electrician is providing some kind of 220v DPDT switch anyway. In the new scheme you would deliver the product with this relay/switch that mounts to the panel. In addition you would need to have them install a 24volt transformer (like is used to control doorbells or zone valves) and an outlet for the microcontroller usb cord.

At that point you are done with electricians and UL requirements since the line voltage wiring is complete and the switch is UL approved. The rest is control wiring and that is low voltage not requiring any special permits or anything. The internet connected microcontroller would mount there or be connected by doorbell wire to some other convenient place (near the router maybe).

You could start now including this relay and even a 24 volt transformer + timer to create a default standard for your installations. Then it is a simple matter to reconnect the 24 volt wires form the timer to the microcontroller.

relay choice

Veris V321 : Enclosed Power Duty Relay, 20A DPDT N.O., Coil: 24VAC/DC, 120VAC, w/2 HOA Switch, Relay Power LED, UL

The Victory 321 DPST power duty enclosed relays combine an industrial-strength relay with installation flexibility...use the nipple mount to attach to any enclosure. One coil input controls the state of two power-rated contacts for simultaneous control of two devices, or both poles of a single-phase load. Each output is enabled with a Hand-Off-Auto switch for local control. The Victory series does not require a dedicated field enclosure, so it is ideal for retrofit projects. Field-selectable high and low voltage coil inputs provide on-site versatility.

• V321 relay
• V321 install
• V321 $36.00

relay revised

Hey what is the breaker like for typical install? A double 20 (I hope) or a double 30 (a different ballgame)?

I have revised my thoughts on the relay a bit. I still do think we should have this feature called HOA (hand on/off automatic) so that if the internet is down you can still go to the relay near the panel and turn it on/off manually. But I think maybe we should use a device with 'HOA monitoring' which sends a signal that our microcontroller can read that will tell the user if the system is working as automatic or maybe someone flipped the basement switch and now it is on manual.

HOA monitoring is only available for 110 volts so now we would need 2 relays. The second relay needn't be high current, it can be a pilot duty relay like this for $21 since it is just driving the 220 relay. The 220 relay doesn't need HOA and can be something like the v320 $27. So I need to know what your electrician thinks of that setup and what you think of HOA monitoring. It changes the system architecture a bit

design decisions

server architecture

There are 2 basic ways to design how the microcontroller talks to the world.

One way allows the microcontroller to be a server and requires that users open a port on their wifi router. This is much the same as Xbox and nintendo requires users to open ports on their wifi routers to play online. All routers are different.

The other way is to have the microcontroller be a client who talks to the internet every 20 seconds or so and gets its marching orders from the servers response. No wifi router settings are necessary.

The first option puts more of the power on the microcontroller device.

my questions to you

We haven't really decided if we are cat5 lan connected, wifi only or wifi AND lan. What do you think? Lan only is by far easier to configure.

I would like you to go to your router and open a port on one of your devices, lets say your laptop. Open port 6438 for the hell of it. Now a server from the outside world can talk to your laptop on port 6483. Was that too hard? Would you not want your customers to have to do it?