Generator advice

Eh, this was for estimation purposes and it was a tedious manual process. It was a combination of using the maximum value on appliance (individual loads i.e. lights, computer, furnace) labels, making generous estimates for appliances with no label, associating each appliance with a circuit, then dicing and slicing each appliance based on categories (priority/default status, seasonality, etc). I hope that I was overly generous on the estimates and that the actual load ends up being a tad less - some overhead on running watts is a good thing.

let’s say I wanted to run my furnace on my generator - do yall just have a plug inline to your furnace that you can unplug if needed. Or perhaps just leave it as is and when the need arises, you go up there with a knife?

It al depends. Ive seen some with naturally with plugs. Otherwise there should be a switch at the unit(Light switch) that you can unwire & wire the “suicide” cord into it.

There’s a TOH on one such product:

Another “correct” way is to add current taps to the wiring at the breaker panel.

For example: https://iotawatt.com/

Mine arrives Saturday.

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Amusing that after ordering the the following last week and awaiting their arrival…

image

… I suffered a ~1:20 power outage today. My UPSs managed a positively heroic 30 minutes of uptime before I was forced to go into minimal mode with the laptop tethered to the phone.

Anyway. After consulting with the internet and some knowledgeable folks I opted for 2 smaller generators in parallel for a number of reasons:

  • Redundancy
  • Actual loads will often fall within the capabilities of one generator, which will be more efficient than running a larger unit at <50% load
  • Smaller and handier units are more likely to see periodic use for projects and other functions beside the chore of a monthly/quarterly “fire up the generator” to-do item

I’m still pondering the ultimate form that the outdoor enclosure will take. DIY’ing a doghouse will be a fun project ala the notorious shed. But a job box would be faster, more secure, probably easier to soundproof, and could be obfuscated with a clever facade; problem being that the smallest job box is too small and the next size up too heavy/more than I want to spend and still has meh access angles for operation. Decisions decisions.

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Probably quieter also.

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Regarding using at home when there’s an outage, is the intent to plug various appliances/cords into the two units when the power goes out, or run a single cord from the main panel to the parallel connection unit and power the whole house (with non-critical circuits off) from there?

The latter - I’m going to properly power the house’s electrical panel via the generator. There are two ways to do this - a transfer switch and an interlock switch. The deceptively-named singular transfer switch is a number of external switches that sit between the panel and the circuits, and with the flip of a switch disconnect mains power and connect generator power to that individual circuit.

An interlock switch occupies two individual slots on a conventional split-phase panel ala a 240V breaker and is connected to the generator. A mechanical device prevents both the main breaker and interlock switch from being closed at the same time.

I’m going with an interlock switch since it’s a cheaper one-and-done affair that can be fed 120V or 240V split-phase. Por Ejemplo:

The red plate is a simple sliding mechanical safety that prevents the main breaker (top) and the interlock switch (in positions 1+2) from being closed at the same time. There is a bit more hand-monkeying with an interlock since you’ll want to open all individual circuit breakers before switching to generator power then switch on critical circuits sequentially so as to stay within the limits of your generator’s capacity (and limit startup surge).

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Lol, Then there is keeping it running in adverse conditions. I was on a site (data center) today where they lost 3 of 8 genny’s in 1 yard. Ol Murphy likes to poke around some times

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I was talking with someone today who had been shutting off his home generators at night, not quite trusting them when he slept. They both suffered ethanol water separation, and one froze and split the fuel filter, and the other froze water in the float bowl to where the float couldn’t fall to allow fuel in. Thankfully he had a third one that was stored inside so he could get the furnace running again, and thaw the one without the split fuel filter.

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I would throw out an alternative: buy an AC clamp (current) meter.

That’s what half of those power logging do-dads really are. If you wanna get fancy, get one with in rush capabilities to capture starting load.

Then multiply (amps x volts) to get (watts).

Maybe a plastic deckbox/bin cover?

https://www.acehardware.com/departments/storage-and-organization/outdoor-storage/sheds-and-garages/7368384?x429=true&gclid=CjwKCAiAhbeCBhBcEiwAkv2cY5jThKNI1FKFlbiK3urI-gEt6V07lDWmX7uzOdTPYPP2DKxJmIOBSBoCAoAQAvD_BwE&gclsrc=aw.ds

I agree with that. I actually don’t have an amp-clamp sadly. It’s been on my list of need to purchase but haven’t had an excuse for a while.

One thing that you might miss is a lot of the meters do reactive loads (VA) in addition to simple resistive loads (Watts) so you can get a feeling of which ceiling you’ll hit first.

I’ve since received my generators and begun the process of breaking them in (note that opinions on this subject vary wildly with some suggesting another 50-100 hours at high load after the third run; I plan on the two unloaded runs then a low-load run).

Observations:

  • WEN ain’t Honda
  • My concerns about noise are real: operating at full throttle these would likely be mildly annoying to my immediate neighbors
  • I will absolutely need an enclosure
    • I’d like to quiet them down to below “eco” throttle at full load\
    • Forced ventilation will be mandatory - internet says minimum 200 CFM; I’ll likely want more
  • Glad I got two smaller generators instead of a single large one
    • Just lugging these things around and doing basic operations I wish they were a tad lighter
    • SOP for backup power ops and maintenance will likely be to pull them out of the enclosure for refueling / oil changes etc; if I had a larger unit that might be a tad bit impractical
  • After the first hour the oil wasn’t dirty like a car would be after several thousand miles but it was cloudy.

Too flimsy, not enough time spent working outdoors in the summer cursing and over-engineering it. :joy:

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Completed the break-in with little drama. Both will run a heatgun or hairdryer at maximum power without complaint.

I did determine that neither generator is happy to start a tiny crappy window unit that I’ve got - overloaded both on first try (curiously restarted on second try without complaint). Suspect that the two units running in parallel wouldn’t break a sweat starting the AC and that I could cheat by setting the AC to more or less never turn off then switching one off one generator - will leave me with very little operating margin, however.

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In a pinch you can spin the squirrel cage to get it going. That little kick may well give it enough of a rotating magnetic field to lower the inrush current. You’re basically acting like a human starter, just like you see on big motors.

I wouldn’t think the compressor should take too much to start since the pressures bleed off.

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Not-quite necro bump.

Finally got the whole shebang running and it was a banner success. Connected the parallel kit, started the generators, plugged the extension cable in, opened all the breakers, closed the interlock breaker, closed critical-load 120V breakers, I’ve got lights again. I was even able to start the office portable AC as the final load without issue.

The noise really wasn’t bad in the side yard with the gate closed. I imagine that a pretty minimal enclosure will cut the sound down to negligible levels.

The general Bill of Materials:

  • WEN 56203i (2) inverter generator ($375/ea)
  • WEN GNA36i 3600W parallel kit (~$50)
  • Custom extension cord (~$100 / DIY)
    • L5-30P plug
    • 8/4 power cable (20’)
    • L14-30R cord end
  • L14-30P generator inlet / 60A 240V interlock breaker / mechanical interlock (~$500 turnkey)

I’m satisfied spending $1400 for a minimal backup power solution capable of running most of a workday. A few more dollars were required for startup consumables - oil, oil conditioner (optional but recommended by some sources), and of course fuel.

Extras:

  • Magnetic dipstick ($10/ea)
  • Jerry cans (2, $45/ea)
  • Sta-Bil (don’t recall price)

All told I believe I’m under $1600 turnkey for a setup that can provide more than a week of WFH backup power.

I will invariably tweak this in the future. I need a fall project and that’s apt to be a doghouse for the generators that will have room for a larger 240V/120V unit should I choose. I’ll likely install a voltage/current monitor of some sort at the panel when I do this. I’d also like to modify a marine gas tank so I can run both generators from a larger common fuel tank so I could truly run them all day, all out.

While WEN isn’t the best brand by any means, the units have worked acceptably during my testing before today’s acceptance trials. The fuel cutoff feature is nice for my use case - turn the things almost off then wait a minute until the residual fuel depletes itself. I’ve kept my spreadsheet reasonably up to date on portable generators.

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I’m going to suggest that the likely next steps are a pair of suction feed gas caps and a pair of 3 or 5 gallon marine gas tanks to feed them.

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Many companies make a dual and some a triple fuel carb for generators (gas, natural gas, and propane). So my next upgrade to the gas generator (which ran my house through the FREEZE) will be a triple threat carb. The preferred power is NatGas, but if ERCOT cuts the supply then there is gasoline, and the last resort is propane for cooking. The real last resort is firewood in the rick, but that won’t cool the house when it is 103’F, and there is computing to be done.

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