Why Bother with Smart Management Modules (SMMs) for Generac Standby Generators?

[@leopoldoramirez2936]

Hey I a m a Florida electrical contractor. Great video. Although generators are not my primary line of work, I do install them on occasion, I also had a service call were a smm went bad and cut power to a clients dryer for 2 days until I could get there. that's the only concern I have with them. Just like anything else is something more that could break, and in my case caused the customer an inconvenient even though she never had an outage. the SSM just simply went out. Other than that. It's a grate and budget friendly attentive to a full house back up generator as far as cost.

[@abrelectric]

I agree. I worry about the same issues with AC condensers in the summer.

[@patlav110]

Exactly same problem with these. 3 of mine have gone out. The contactor needs to be redesigned so that street power does not go through it all the time. When these things fail, it kills the power to the device even when the generator is not running. These are usually key appliances like AC units. Not going to have a generator control my everyday life.

[@leestokes6761]

I live in American Fork, Utah. I grew up in St. George, Utah. Compared to St. Gerorge Municipal Power (remnant of the 1930s REA) my current power company (Rocky Mountain Power), my electric power is extraordinary stable. The joke in St. George when I was a sarcastic teenager was if a bird landed on a power line and pooped, the power went down. In fairness, the system was growing so quickly, the city had a hard time keeping up. I turned 10 in 1965-the population was around 3,500. When I graduated from Dixie High School at age 18 in 1974, the population was pushing 12,00-14,000. Where I live now, we experience an outage perhaps once a year-if that. Average outage is 5-10 minutes. The longest outage I remember was about three hours. St. George had several 12-24 hour outages when I lived there-but again not much you can do at the end of a several hundred mile transmission line if that line is taken out by a small plane crash or a forest or brush fire. If I still lived in St. George, I’d consider a generator. In American Fork, I’m not too sure I need one. Though my wife is agitating now and again for one. So, I am kicking it around. We’re both 67. If either of us ended up on oxygen as we continue to age, a generator would become a necessity. What holds me back is I would need to take on much of the work to keep costs down. The wiring and gas plumbing are pretty straightforward. Service entrance is about 15-16’ from the gas meter. No underground utilities between them. AC compressor is between them on the same side of the house. Do you have any suggestions on where I could learn how to properly size a generator? Could I calculate my average daily usage from my most expensive electric bill (summertime A/C use) and use that as my basis?

[@abrelectric]

I would size the generator based on your priority load during an outage. For an extreme example, if you really only needed power for two oxygen machines, you could simply get a small, quiet inverter style generator (3kw) and simply run a few extension cords for the duration. Going the other way, prioritize the large loads: AC condenser, electric water heater, electric oven, etc. The more large loads you need the larger your generator will be. Your generic lights and plugs use very little power. My parents lived near St. George for a bit in the early 2000s. Pretty country.

[@michaeladams9129]

Great video, thank you, James! I am definitely one of the electricians that just tells my client to use their head and lets back out the whole house. I do like the idea of using a large contactor to isolate some of the non-critical loads to eliminate some of the possible challenges you mentioned. I have thought about somebody being away from home when the power goes out. Thank you as usual for getting me to think about things that don’t cross my mind sometimes!

[@abrelectric]

Sounds like you're an awesome electrician and take care of people

[@clayfischer7768]

Great video. Thanks for sharing your experience. I have installed SMMs on most of the generac whole home systems in my area. Great way to power a 37kW load with a 22kw gen for example. Have seen quite a few modules fail 2-3 years after installation. So plan for a call back if you use them.

[@abrelectric]

Yes, thank you. I've had several people recommend the PSP load shed module instead. Have you heard of that brand?

[@waterboy74]

@@abrelectric I have two of the PSP SAK 60s in my house to shed about 20kW of load (double oven and an HVAC system w/ heat strips). Haven't actually overloaded things to see what happens with the generator running, but can confirm that they work great as far as delaying the loads coming back online after a power loss. It seems to be a very well built piece of hardware/software with lots of configuration options. Here's a pic of one of mine: kzbin.infoUgkxJPesuqTlTrnFxLFuX4PTRft6Xmn2emHu Here's a link to the install manual also: www.pspproducts.com/wp-content/uploads/2020/12/SAK60Install5.5x8.5V112320.pdf

[@abrelectric]

@@waterboy74 thank you!

[@bobrader1920]

Great video, We just upgraded to new furnace and a/c also updated new electrical panel. The home came with a Generac 8kw generator so this will not power ac or hot water tank so we installed one SMM on hot water tank and I am going to order SMM for a/c.

[@RealDeanWinchester]

I back up my whole house with a 10kw generator. My large loads are 2 water heaters, central air, clothes dryer, and a well pump. I put soft starters on the central air and well pump. The two water heaters and central air are allowed to run 20 minutes each during any given hour. The dryer is disabled. If I want to run the dryer i press an "override" switch which allows it to run for one hour, the water heaters and central air are disabled during that time. The generator and transfer switch are controlled by a PLC. I used normally open contactors for everything except the central air. The 24Vac that from the thermostat is routed through a relay output on the PLC. If the generator frequency drops below 55 hz all managed loads are disconnected for 20 minutes. If it drops below 55 hz during that 20 minute period the generator shuts down.

[@abrelectric]

Sounds like a good setup

[@johnstraley9057]

Informative content. It only makes sense to design a whole house standby system with load shedding capability. The thought of wondering whether or not one feels a need to pacify an inspector should be a moot point. It's more of a concern to get the the load analysis, system sizing, location and installation properly completed by licensed professionals. A smooth inspection should follow.

[@Neil-fw2qx]

Great explanation. Thanks. I have one of these on my dryer. It’s a vacation home. The dryer stopped working after a recent power outage where we were not at the home. By process of elimination I determined that the switch was at fault. I disconnected and wire-nutted load and line wires. The dryer now works. I’m not sure I even need the switch. It was here when we purchased the home. Can I leave it bypassed and is there a better way to connect the wires? Also wondering if test button is also the reset button.

[@rbrown2925]

Looking for a generator, I’m mostly concerned about the startup surge when we’re home, since you only have 10 seconds to turn things off before startup. When we’re away, the only big loads are the 3 and 4 ton ACs and a few lights, so nothing much to worry about. We were thinking about putting one or both ACs on LCMs and a Kohler dealer says their 20 kW gen has great surge capacity so the LCMs aren’t necessary, while another dealer who sells Generac and Kohler says we should have them, especially with a Generac. All opinions on the need for LCMs with a 22 KW Generac or 20 kW Kohler are very welcome!

[@trith72]

I got a Generac 24kw installed a few weeks back and on my test run I had both my ACs( 3 and 4 ton) running, washing machine, my office computer equipment and my electric oven, two small window ac units running and the generator never missed a beat. I even ran up and down the garage door a few times and tuned on all 3 tvs in the house. I honestly couldn't think of anything else to even turn on to test and the electrician was like "don't worry about it, you are not going to overrun this generator"...he was right. I ran two hours test and life as normal in house didnt make it break a sweat. I probably could have gone with a 18 to 20kw on my house but buying up to 24kw keeps me from needing the SMMs. 4k square foot home and boat house all powered easily from the 24kw. The installer did have the gas company come out and put a much bigger valve on my meter to increase flow. The meter itself is an Intelis Gen 5 250 BTU and I figured they would have upgraded it, but the gas man told me a dirty little secret, most of these new residential meters will easily push over 500k BTU as long as you have the right valve and Pipe size allowing the flow from the street. They upgraded mine and said I would never have to turn anything off gas wise to keep the generator running.

[@abrelectric]

That is awesome!

[@pokerpirate4034]

I'm a Florida homeowner, not an electrician. We've been in this house for three years and the 22KW Generac is less than four years old. We have three A/C systems, each with it's own SMM. My feedback is that in about three years we have replaced two of the SMM once and the other one just failed for the second time, so it'll be four failures in three years. At about $375 a pop to repair/replace, I'm getting to the point of just wanting to bypass/remove the three SMMs from my system. Our worst scenario is that we're away for a month and the day after we leave home, the generator kicks on, can't handle the load, then shuts down causing the home to be unpowered for a month. The biggest cost for me is food loss due to refrigerator death and the house gets hot....but we'll never have the worst-case scenario of a winter deep freeze and all the damage from frozen pipes.

[@abrelectric]

@pokerpirate4034 I've begun changing over to PSP load shed modules. Several subscribers recommended them vs the Generac SMMs.

[@MTBTrek34]

I have been reading these SMMs fail often. I think mine finally failed on my AC condenser probably in about 3-5 years. Not bad. Dunno what causes them to fail however.

[@nickcasesa1774]

and yes. great video..thank u

[@georgebennett785]

I would be most interested if you would explain in detail the set up procedure of this module. Lockout switch setting, LED states, (A)Priority setting, (B) Lockout switch, (C) Test, (D) status lights, and if module failed how to bypass relay coil if energized so you may use appliance

[@timothyhargadon752]

Wireless? How does it detect frequency wirelessly? I have one of these on each of my A/C units.Thank you for a great video.

[@abrelectric]

@timothyhargadon752 actually, independent may be more accurate. It's a normally closed relay that will open (shed) on a load when the generator power frequency is altered by a heavy load.

[@greatwhitewing]

Do the load shed devices turn back on (closed) once the un-shed load goes back down?

[@abrelectric]

Yes, depending on how you set them. The Generac SMMs has a slide switch to set that.

[@EngineerMikeF]

Anybody know how the modules communicate to follow the priority settings?

[@KenEdwards-k1d]

We were sold a 8kw about 12 yrs ago for our cottage which became our home. We have an ATS with h the usual dedicated switches. Our main consumers in the switch are a heatline for drawing lakewater in the winter/ jet pump and sewage pump/furnace AC 1 freezer 2 fridges various lighting circuits. We’ve since installed a 240 volt small hot tub. Would one of these devices help? The hot tub is not on the ATS and my worry is that the tub may freeze while we are away

[@ryana5191]

Hi! Really great video but I have a question. What if one of my four modules is blinking and is not getting power (it’s for the dryer)? The others are for the pool and oven. Do I go to the breaker and turn those off that way or some other way in the generator to power the dryer? Thank you for your time!

[@kevonslims7269]

How do you size the load shed box for each device, like A/c stove ect ect.

[@Beeper22]

Is there a video to bypass these after installed? My mom purchased a house not long ago that has these installed. One went bad and not looking to buy a new one and have installed due to cost right now... however, AC is off and with her in her 70s and in Texas, I needed to get this AC up and running now. I am not having luck on how to bypass this for now safely. She has a 3000 sqft house and 22KW Generac so ample power

[@abrelectric]

You can make sure the Lock Out Disabled switch is all the way to the right. You can shut off that breaker, and splice the 2 hots together to bypass the relay.

[@SniperX611]

That's such a huge box! They need to make a smaller package

[@KUSLERYACHTSALES]

How do you minimize the HUMM from the unit?

[@dondorfman3951]

Not an electrician, an mech. engineer. I was wondering if the PSP basic contactors would be a more robust solution? Voltage VS frequency controlled and no wireless which I know saves time wiring but adds an element of potential failure. I am looking at an 18kw and 26KW derated to 24KW due to natural gas) would power my whole house. If a manual transfer switch is used is load shedding still required by code? On the fence.

[@abrelectric]

I am hearing that PSP is a far better solution. I have yet to try them myself.

[@abrelectric]

If you're using a portable generator, the those particular Cide requirements don't apply.

[@annaszmitko2145]

Hi. Where to connect a diy contactor setup to the ats to do loading shedding.

[@BarnDoorEnterprises]

We have a 11 kw pv system with a whole house battery backup system installed in May of 2021. About a year into our system we have had a continual problem with these generac SMM modules. They keep failing which as you know completely shuts down power to those circuits that it's connected to even after the power from the grid comes back up. We've had several replaced only to fail again. Of course there's only a one-year warranty on these things and the company that did our installation has gone out of business leaving many with a nightmare situation. Since these SMM modules seem to be fairly problem-free across the board. I am left to believe that our system was not set up properly. I am trying to learn and understand so that we can have a functioning system. Any words of wisdom you care to share?

[@RobGuercio]

I have a 30 kva 3 phs water cooled Generac. My one smart module (006873-0) which just failed, so for now i bypassed it. It's on a 3 ton AC which is running on single phase so my question is it seems insignificant and i question if i really need it. I have 2 five ton ACs (which are 3 phase units), a 1.5 hp pool pump, 2 frigs, 2 freezers, a over range and stove top, e dryer. Heat is Gas for ACs and Water. Anyway do you think i need to replace it and if so what brand and model do you suggest.

[@abrelectric]

@@RobGuercio I'm not sure you need the load shed for that 1 phase 3 ton unit. If you do, use one from PSP

[@abrelectric]

@@RobGuercio I'm not sure you need the load shed for that 1 phase 3 ton unit. If you do, use one from PSP

[@RealDeanWinchester]

The manage your loads yourself plan works great until it's your wife or kids that have to do it.

[@abrelectric]

There you go.

[@robertvandell8987]

If mounted in direct sunlight, the brand you show last about a year and a half.

[@abrelectric]

@@robertvandell8987 we are transitioning to PSP load shed modules. The Generac SMMs are problematic without direct sunlight:)

[@jsracz]

Great video! all about politics here, the generator was sized to power everything in the house and then some. The inspector said "I don't care I require the modules" the electrician who installed the generator thought it was ridiculous but nodded and said yes sir and installed them. They're garbage, needing to be replaced every two-three years at best as some others have mentioned here. I mean come on Generac be better, or they know exactly what they're doing because when you look around this issue has been going on for years now.

[@tatermorgan6559]

My generac load shedding module kicks in and out all day. How can I fix this?

[@abrelectric]

I don't know. Anything obvious in the troubleshooting section of the instructions? Any loose connections at the coil on the contactor?

[@brianvanness783]

If it is doing that while the generator is off, it’s either faulty or you have a something upstream going on. Do your lights flicker?

[@billyreastmanjr6176]

You could just use a soft start on your ac unit

[@alansabin7487]

it's a back up, you don't need to put the whole house on it.

[@jeffleary1598]

150 bucks each Need 3 Plus install = home owners claim It’s a pain in the ass to be honest And when them smm’s go bad they snap and click and sound like transistor box for electric fence Kind of intimidating

[@abrelectric]

I agree. The alternative is to hardwire the control coil wiring to all the load shed NC contactors. It just adds a large layer of cost.

[@JJG84679]

Have a 22k generator. I'm not home most of the time. Seems like a waste replacing the module every two years. Tops my heat pump and dryer might be on simultaneously when I am home. It trips my hotwater tank. Ridiculous. Feel like it's a con job for more service calls

[@Jeff-ts5mr]

all those appliances would stay off and would have to be turned on one by one.

[@RHP2024]

wait a minute. you forgot 1 other way.

[@scottbeckius7756]

Keep spares of these units on hand. These are a terrible design and they don't last long, year tops, and then you get to replace them

[@nickcasesa1774]

Terrible Product.. I have 3.. one was replaced under the 1yr warranty.. yr 3, 2 more went (including the new one)... Just got the quote from the electrician to replace 2...$1200. this person services my generac... I mean rip off?? so fired ...I spoke with Generac and they do not care... I purchased 2 new modules for ~$300. replacing myself. I agree we can self manage but if we are away etc it could be a problem.. so the pool one stays but do I really need a module on a steam room?? it does not automatically go back on and barely used... poor planning on original install ...

[@MrSamsamsammy]

These things suck. We use PSP’s stuff and have never had an issue with them

[@abrelectric]

Thank you - who is PSP?

[@abrelectric]

Just looked them up - very interesting