Indigo and Backup Generators

This is the learning so far in trying to solve for the following use case:

A whole house backup generator kicks in automatically during power failure and
'brown outs'. Need to turn off all non-essential equipment when the generator
kicks in.


So the scenario for the use case so far looks like this:

Utility Power goes out >>

Four Pole ice cube Relay opens circuit to non essential equipment(see diagram below), Mac powers down,
backup generator starts up>>

Backup Generator is up, Mac powers up and Indigo pings an IP device on the utility side only
to determine when utility power is up >>

Utility Power comes Back>>

Indigo checks if Utility Power has been stable for some 30 minutes.

If Utility power has been stable Indigo to send a 'restore' signal to the ice cube relay.(I
still have to source a IP to contact closure device.)

Aiport Express Bridge Mode

After much trial and error I now understand how to better use the Apple Airport Express(AX). I hope some of you can save some time with this information.

Senario 1 - Use if streaming music with iTunes and/or Sharing a printer.

I assume you have a router connected to the internet set up with a WEP security key for wireless access by your PC's. Using the AX airport utility software select wireless mode to  'Join an existing network'. The AX ethernet port will be disabled. I could not get WPA security to work in my configuration.

Senario 2 - Use if streaming with iTunes, sharing a printer and 'extending' your wireless network.

Again, I am assuming that you have a router connected to the internet. Connect your AX with a ethernet cable to the router. Yes you have may have to pull cat5/6 cable. Using the AX airport utility software select the wireless mode to 'Create a wireless network' and set connection sharing to 'Off (Bridge Mode)'. Note that you are always creating a new wireless network(SSID) even if you decide to set it the same as an existing SSID. If you do decide to use an existing SSID then set the wireless channels to be different on each router.

There is a third wireless mode called 'Participate in a WDS network'. My experience after using this mode is that it is not worth the effort. The configuration is complex and the loss of speed is proportional to the number of WDS clients. Pulling cable is easier or invest in a dedicated wireless bridge - really.

Rate of change

I am monitoring the outdoor vs indoor temperature to understand how the house performs from an energy point of view. It is interesting to see the effect of the mass of the house on temperature changes.

Chart of indoor vs outdoor temperatures