Generator inlet receptacle installation on house

Power out? How about an inverter connected to your car?
kevm14
Posts: 15200
Joined: Wed Oct 23, 2013 10:28 pm

Re: Generator inlet receptacle installation on house

Post by kevm14 »

Naturally I wasn't going to just let this go.

Final circuit list:
WP_20151005_19_13_31_Pro.jpg
200 Stony circuits 10-5-15.png
Final phase balance:
200 Stony circuit phases 10-5-15.png
Analysis for loads of any significance, that I might use during a power outage:
Phase 1: Washing machine (unlikely but maybe), great room entertainment, upstairs bath (possible hairdryer), master bed/computer, microwave, fridge, furnace
Phase 2: Garage lights & openers, air compressor (highly unlikely), downstairs bath (maybe use hairdryer down here for balance), basement lights, coffee machine, toaster, hot water heater

Add to all of that the well pump (on both), which is somewhere around 1200-1300W I think. And not sure which burners on the cooktop are on which oven breaker phase.

For phase 1, I would say it might be best to avoid the microwave while the furnace is on. Or simply move it to the coffee/toaster/radio outlets. One nice thing is the master bed is on the same phase as the furnace. Well, that means if I used the A/C it wouldn't be competing for power with the furnace. That's something. Just have to remember to turn the master bed A/C off before using the microwave (or switch microwave to phase 2 as mentioned). Master bed A/C would only be used at night (probably for a couple hours before generator shut down), so there's not as much load juggling as I'm making it seem.

For phase 2, all I might suggest is avoid toaster unless other phase 2 loads are very light.

Phase 2 appears a little less burdened in a power outage scenario but overall, I don't think this is terrible.

Knowing about this will enable me to have a relatively good experience during an outage (i.e. minimize equipment failures or breaker tripping). And overall this is a good education that there is more to generator sizing/loading than just total watts/VA consumed. In fact, I'd go so far as to say phase balancing is MORE important than trying to add up peak starting loads. I think the peak capacity of a generator is largely uninformative and not useful, compared to the total continuous capacity, and capacity per phase (particularly regarding the way the breaker box distributes the loads).
kevm14
Posts: 15200
Joined: Wed Oct 23, 2013 10:28 pm

Re: Generator inlet receptacle installation on house

Post by kevm14 »

I switched the two great room circuits. Now the entertainment stuff and lights are on phase 2, which balances out better.

Updated circuit list:
200 Stony circuits 12-20-15.png
Updated circuit phase balance list:
200 Stony circuit phases 12-20-15.png
kevm14
Posts: 15200
Joined: Wed Oct 23, 2013 10:28 pm

Re: Generator inlet receptacle installation on house

Post by kevm14 »

kevm14 wrote:Close. Looks like it is actually the GE-200XL

http://www.geninterlock.com/product_gen ... ctric.html

Specs:
•200 amp single handle Vertical throw down (off), up (on)
•3 1/4" to 3 1/2" spacing between Main and first breaker
•Generator Breaker: Top left side 2 positions
From the website:
ge200xl_i_lg.jpg
ge200xl_u_lg.jpg
And here's mine:
WP_20151005_16_33_27_Pro.jpg
Looks like a match. At $75, this is both cheaper, easier and less complicated than a whole service transfer switch.

Here is my panel info for future reference:
WP_20151005_16_33_33_Pro.jpg
Electrical crew are here for the kitchen. They looked at my panel and said if I ordered this lockout plate, they would install it as part of the work. That's cool. So I ordered it.
kevm14
Posts: 15200
Joined: Wed Oct 23, 2013 10:28 pm

Re: Generator inlet receptacle installation on house

Post by kevm14 »

And it arrived. I put it next to the breaker box. It will be good to add this layer of safety even though there was basically a 0% chance that Jamie was ever going to attempt to hook up the generator herself.
kevm14
Posts: 15200
Joined: Wed Oct 23, 2013 10:28 pm

Re: Generator inlet receptacle installation on house

Post by kevm14 »

Post kitchen remodel, here is what I am working with. Yellow highlights are where changes occurred from my last analysis (all but one were from the kitchen). Some new, and some just got moved. And part of that was because of moving the generator breaker up to the top left slots to accept the lockout plate.
200 Stony circuits 110119.png
And now the updated phase balance list:
200 Stony circuit phases 110119.png
Looking at it, I am mostly happy with it. The fatal flaw before that caused one of the phase breakers to trip on the generator was likely due to running the Keurig and dehumidifier on the same phase. So what I did was plug in the Keurig to the next outlet which grabs the other phase and haven't had an issue.

I did figure out that the "A" circuit for the kitchen counter outlets begins where our phone chargers are. So that'll be easy to remember. Then it just alternates going around the room, A, B, A, B, etc. Right now the Keurig and toaster are on the "B" circuit so they shouldn't be run at the same time, either. Jamie did use the toaster this morning and it was fine.

Microwave is on phase 1 so again that is good. But I may want to just throw the dehumidifier breaker because it doesn't seem like an emergency to run that when on generator power. It's still on...

As far as an overall assessment here are some things:
- Furnace and hot water heater are still separated. This is good.
- On phase 2, the main things going on other than lights look like the water heater and refrigerator. Dishwasher, too, if it is an extended outage. I'd have to manage something to add that. Otherwise the phase 2 is sort of lightly loaded.
- On phase 1, the main things are computer in master bed, kitchen "A" outlets (most stuff is on this like toaster and Keurig), dehumidifier, furnace, great room (TV stuff) and microwave. This is kind of heavily loaded and this must be the phase that blew. Handily, it was the top breaker so I can consider the top breaker on my generator to be "phase 1" in my table here. I think I would consider moving the great room to phase 2 as TV watching is a thing during power outages.

Going further on phase 1, it is conceivable that the following loads could run simultaneously:
- Upstairs computer (180W or so)
- Keurig or toaster (I would just manage this to be an either-or)
- Dehumidifier (so may be a good idea just to shut off)
- Furnace
- Great room TV stuff which could be upwards of 300W
- Microwave

Yeah that is too much. I think if I pulled the great room over to phase 2, the CONOPS would look something like this:
- Keurig or toaster or microwave (elective)
- Furnace (runs autonomously)

Now that should be OK, plus small additional load for lights.

On phase 2, here is the situation:
- Anything on the kitchen "B" outlets, which is nothing right now
- Water heater (runs autonomously)
- Fridge (runs autonomously)
- Dishwasher or TV stuff (elective)

I kind of backed into the strategy. You want to make sure the autonomous stuff has as much flexibility to go on and off as it needs to. Then for elective loads that are significant, you just group them and decide which you can run simultaneously, and which need "OR" logic.

But yeah that doesn't look half bad. I guess just move one breaker over to the other phase. Cool.
kevm14
Posts: 15200
Joined: Wed Oct 23, 2013 10:28 pm

Re: Generator inlet receptacle installation on house

Post by kevm14 »

Swapped the basement bench light breaker (it is a 20A but everything is elective like shop vac or whatever else I may plug in) with the great room outlet that does the TV and stuff.

Final looks like this:
20191101_115341.jpg
Final circuits:
200 Stony circuits 110119 final.png
Final phase balance list:
200 Stony circuit phases 110119 final.png
And this is what I am hanging on the fridge for reference:
generator phase CONOPS for fridge 110119.png
kevm14
Posts: 15200
Joined: Wed Oct 23, 2013 10:28 pm

Re: Generator inlet receptacle installation on house

Post by kevm14 »

Whoops. I identified the Keurig and toaster on the "B" circuit and then somehow put them on A in my mind. Fixed the CONOPS stuff.
200 Stony circuit phases 110119 final fixed.png
The good news is, I can easily switch the toaster and Keurig around to A or B just by moving them over to an adjacent outlet. So I have some good flexibility there going forward.
kevm14
Posts: 15200
Joined: Wed Oct 23, 2013 10:28 pm

Re: Generator inlet receptacle installation on house

Post by kevm14 »

And it also turns out the electricians mislabeled the microwave and refrigerator breakers. They reversed them. I have corrected it on the panel label and my spreadsheet. So the correct update is this:
200 Stony circuits 1-26-20.png
200 Stony circuit phases 1-26-20.png
No wonder it overloaded a phase!! I have to rebalance again I think. I will analyze and figure something out.

If I switch the great room over to phase 1 (I think I already switched it to phase 2 in this thread), that might help. Then I can just focus on running one kitchen appliance at a time. That kind of makes sense I guess.
kevm14
Posts: 15200
Joined: Wed Oct 23, 2013 10:28 pm

Re: Generator inlet receptacle installation on house

Post by kevm14 »

I made some notes on the printout on the fridge but I need to update the Excel file for CM purposes. And probably print a clean version.

Also I am really toying with the idea of buying two load monitors with digital readouts so I can keep tabs on the amps per line/phase when the generator is powering my panel. That will really help confirm my load balancing and overall generator load. I would mount them on my panel in the basement and they'd only be active when on the generator. I could also temporarily monitor grid input power and get a feel for the load balance but it wouldn't be that relevant unless I ran the more strict generator "CONOPS." Which I could do. I could even monitor individual circuits to get a more precise understanding of each load and plan more precisely. An experiment while on the generator is more exciting though, even if it is just a test when the grid is up.

I have watched a few videos on this and combined with my EE background I have concluded that the single most important value to watch is amps per line. Watts is not relevant. The generator is really rated in kVA not Watts even though people use "Watts" as the unit. It comes down to power factor. Not all loads are the same so kVA is what you need to track. That said I wonder what the on board LED load monitor is reporting on. It could actually be amp-based.

KW are tracked at home because you are billed that way from the grid even though your actual grid demand is defined by kVA. Industrial customers are billed in accordance with overall power factor and are penalized by tier for lower power factors. Generators, wires and breakers all deal in kVA but we are conditioned to kW. Interesting huh?

Also I posted this whole thing from my phone. Ugh.
kevm14
Posts: 15200
Joined: Wed Oct 23, 2013 10:28 pm

Re: Generator inlet receptacle installation on house

Post by kevm14 »

PowerBack hasn't been working right for some time. At the beginning of this outage I decided to pull the panel cover and inspect. What I found was the inductive pickup that is wrapped around one of the main legs was somewhat loose and unraveling. I simply tightened it. And just now it worked perfectly to alert me the second power was restored. Which is good because the map still thinks I don't have power.
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