Tragic day for my snakes.

[tcutting]

With a Herpstat model that includes the safety relay it has a relay inline with the solid state components. You enable the safety relay in the menu which can tie it into your settable High / Low temp alarms. So when your alarms are breached it will beep but will also trigger the relay cutting power to all outputs on the thermostat. This is what protects your against a runaway heating situation.

Those models would be the Intro+, Herpstat 1, Herpstat 2, Herpstat 4, Herpstat 6.

There are devices out there that do the text/email alerts. We've investigated that idea several times but unfortunately the explosion of "Internet of Things" products out there has also exploded with exploits and security holes. So now you not only have to worry about a hardware failure but also internet security, router configs, and so forth. Email alerts are like finding out your home is on fire. Its good to know but its better to put the effort into preventing the fire in the first place.

Keep in mind a mechanical relay only thermostat has a limited contact life with the biggest problem being when the contacts are released there is a spark that wears on the contacts. One of the reasons we have some special sauce in our Herpstat HP to minimize that. Not to mention if you are using it for regular temperature control of an enclosure the relay clicking will drive you mad.

Dion Brewington
Owner, Spyder Robotics

So its been a crazy long time since i updated this post and even had time to work on this project. (i have since been running a far safer thermostat solution since then) but I am getting it going again.

To your point about IoT and the security needs for it, I actually work in the cyber security field and have been at it for over 10 years. I am aware of the design challenges required to make this work and keep it from being an access point for attackers. My goal is to have it only send out encrypted data and not allow anything inbound. Well at least not directly. I have an SSL vpn configured for my home with Dynamic DNS setup so I can remotely connect to my home as it is. I use this for my Home assistant system which has no route path to the internet configured.

Anyway, I have solved some of the issues I needed to deal with recently and should hopefully have a working prototype by the end of dec. Ill try to update this thread, or start a new one depending on if people are interested.