Detecting utility power restored while on generator

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This topic was discussed here...

https://community.hubitat.com/t/utility-power-restoration-notification-for-when-on-generator/133556

...but was closed due to inactivity.

I have the same problem, but maybe a little worse becuase my load center is on an outside wall and the devices like the Briidea and PowerBack are "indoor only".

The portable generator is connected to the house load center via a power inlet receptacle hanging off the load center and an interlock kit.

When on portable generator power, my HE, security system (Elk M1G), network, and Internet access will all be on powered circuits (and UPS's), so they will "always" be up.

As the OP on the other topic stated, I'm looking for some way to close a relay when the power restoration device sees the utility power restored. I can wire the relay to a M1G zone to detect utility power restoration, and the rest is easy.

Anyone know if the main components for the commercial power restoration devices are publicly available, i.e., the components that sense power and do whatever it takes to power/sound the alarm (which should be enough power a relay closure)?

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https://a.co/d/5VyQsQW

Or build your own version of this, Google inductive A.C. power detector. Several transistors, resistors, etc., and a coil of wire to inductively pickup AC presense.

Then as you said wire into sensor...

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I use one of these - it’s kind of fickle though

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Is the whole home powered by the portable generator or only some circuits? If there are any outlets that are not powered, you could use a Zooz Range Extender and use the battery/main attribute to trigger a power back alert.

I use these to alert me when the power goes out so I can shut the hub down before the UPS runs out.

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At a minimum you could sign up for texts/emails from you utility, if it offers that.

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AC present - relay schematic
AC present - relay schematic1184×796 111 KB

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He mentioned that he had an interlock, so the whole home.

I've never had a house with an outside panel. It would also seem inconvenient if you had to flip a breaker for whatever reason.

If he had a standby generator, it would have a automatic transfer switch, which would come equipped with a dry contact switch that could be used to determine house power status.

If there was enough room inside the panel, perhaps a PowerBack type of device could be hacked to trip a Z sensor, also inside the panel box. The signal might not get out though, and you'd have to rig an external antenna. Or, hardwire to an external plastic box where the sensor resides.

CT-type relays are available, I believe. You could install it on one of the utility legs. It closes/opens a relay. Self-powered. There is a RIB version.

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The outside panel is essentially used as a service entrance disconnect. An outside disconnect is required here, and the panel is cheaper than a true disconnect switch. It feeds another panel that is indoors. The outside panel only has a breaker for the portable generator power inlet (which is directly below the panel) and a breaker used for the whole house surge protector. It may have other breakers later for outdoor circuits that don't need to be backed up.

A large majority of new homes in this area (50 miles south of Houston) have a single load center mounted on an exterior wall. I've never liked that because I don't want to go outdoors in bad weather to mess with breakers. That's why I have this setup.

The setup is actually a little more complicated. It goes meter can -> outside panel -> indoor ATS -> indoor panel. The home is under construction. The plan is to install a standby generator after we move in. The outside generator power inlet is installed in case it takes us a while to get the standby generator. After that, it will be the backup plan for power outages, i.e., if the standby generator has a problem. I already have the portable generator, so it made sense to add the power inlet at the new house.

99% of the time (when the standby generator is providing power during an outage), this device won't be necessary because the ATS will determine power restoration and the ATS also has a relay to signal power restoration. This device will only be useful during an outage when the standby generator has failed, and I have to run off the portable generator (assuming it is working correctly).

I guess I could have hung the power inlet off the indoor panel, but that was more work (brick veneer wall, available breaker slots, etc.).

This setup may seem like overkill (ATS and standby generator, and power inlet and portable generator as backup), but it would have helped me in the past. During one outage that lasted a couple of days, the standby generator failed to start. Because widespread outages around here usually result in a lot of standby generators failing to start, it took a while to get a service tech to fix mine. And yes, it was exercised weekly, and in this event, it had exercised correctly a few days earlier.

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Was that the cold weather event where even the natural gas delivery system puked in places? That's not good for standby generators.

I started with an interlock and then added a standby, mostly for my wife (at the time, lol).

I still primarily use the interlock and avoid using the standby whenever I can. I use that PowerBack, but my feed goes into the basement.

I have a 1000 gallon propane tank, and it's still filled to the max 75%.

My usual scenario is: lights go out, maybe 15 seconds go by, and the standby kicks on. Then I can figure out what to do. If it's a blue sky kind of outage, I may just shut it down or let it run. Longer, I'll run water in the tub, take a shower, whatever uses the well, which needs the Big portable, which I don't want to lug around, lol.

Along with conserving propane, the usual residential standbys just have glorified, if that, lawn mower engines. It's not like you can just let them run unattended for the length of an extended outage. At best it'll shut down on low oil level.

I'm in a cool climate and don't even have A/C. I heat with oil and firewood so that takes very little electrical power to work.

So, I basically run the house on a Honda 2000i generator plugged into the interlock inlet.

Except for overnight, when I shut the generator off and run the refrigerator and wood stove fan on a couple of Bluetti AC180 batteries. I haven't tried the oil boiler alone...I guess I could estimate run time, but I haven't.

It's a new house-are you getting a smart meter? Theoretically the utility should know specifically when you are restored and could notify you in a timely, automated fashion. Theoretically, lol.

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The RIBXKTF you linked to is a current transformer. That won't work because when utility power is restored, there won't be any current draw on the line-in due to the interlock kit.

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That outage was due to a freeze, but it was back in the early 2010's (not the really big Texas freeze in 2021). That standby generator and the home were fueled by a 500 gallon propane tank because I didn't have natural gas there. I think the failure was due to a failed crank sensor.

The new house has natural gas. In this area, natural gas availability is extremely stable. I've never lost it at my current home, and I've never heard reports of it being lost around here during hurricanes or freezes.

I had installed a standby generator at the previous home three weeks before hurricane Ike in 2008, which caused a four day outage at my home. The generator ran flawlessly. After that hurricane, I decided I would always have a standby generator. It would be a cost of the home.

Natural gas is a lot cheaper than propane here. I have a 26KW generator at my current house that uses about $1/hr of natural gas when running at 50% (it almost always runs at less than 50%).

I'm pretty lazy. If utility power goes out and the standby generator starts and runs like it is supposed to, I just sit back and smile for the duration of the outage. The portable (Champion 7500W open frame inverter) only gets hooked up when the standby generator doesn't do its job.

My previous home had a 22KW liquid cooled 1800 RPM generator (2.4L Mitsubishi truck engine). The longest outage I had with that one was four days, and the generator ran fine continuously. Current home has a 26KW air cooled (999cc mower engine) on natural gas. The only reason I went air-cooled on this one is because I wasn't planning on staying here very long, i.e., until the new house was finished. Haven't had an outage with it, but dealer said it needs to have the oil changed after four days of continuous operation. The new house will have a larger liquid cooled 1800 RPM generator on natural gas.

Almost all long outages here are due to hurricanes, i.e., summertime when AC is a must. I didn't lose power at all during the 2021 freeze. I think this house is on a circuit that is deemed critical. We lost power for 36 hours after Beryl, when many less than a mile away were down for several days up to a week. Short (less than a day outages) are also very infrequent (maybe less than one per year), and most of those are less than a couple of hours.

I'm not depending on utility notifications. The ATS and home security panel will be able to provide me with all the notifications I need. The setup will tell me (via voice announcements and text messages) when utility power is lost and when it is restored, when the generator is running (even during weekly exercising), and when the ATS switches between utility and generator. I had the same setup at my previous house. When an outage occurred, I would get an announcement that utility power was off. Fifteen seconds later I would get an announcement that the generator was running, Ten seconds later I would get an announcement that the ATS switched to generator power. I got similar announcements and messages when utility power was restored. I'm not depending on the utility company or the Generac app to tell me any of that.

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That’s true. Duh.