The Portable Generator
Hookup & Sizing Playbook
Size it right, hook it up legally, and run it safely: running vs. starting watts with a worked example, transfer switch vs. interlock without the sales pitch, the carbon-monoxide rules that save lives, and a print-and-tape-it-to-the-panel outage checklist.
Get the full guide — $17Sizing by watts: running load vs. starting surge
Every generator box screams two numbers: starting (surge) watts and running (rated) watts. Size your purchase off the running number plus your biggest motor's surge — here's why. Motors (fridge compressors, well pumps, furnace blowers, AC) draw 2–3× their running watts for the few seconds they start. Everything else — lights, TV, chargers — draws what the label says.
The worked example — a realistic "keep the house livable" subset:
- Refrigerator: ~200W running / ~1,200W starting
- Gas furnace blower: ~600W running / ~1,600W starting (electric ignition + blower)
- Sump pump (1/3 hp): ~800W running / ~1,600W starting
- LED lighting for the rooms you're in: ~150W
- TV + internet router: ~200W
- Phone/laptop charging, misc: ~100W
- Coffee maker or microwave (one at a time): ~1,200W while running
Add the running loads: roughly 3,200W. Now the surge check: the biggest single starting event (furnace blower, ~1,600W) replaces its running draw in the math. Total continuous need stays under ~3,500W, with surge headroom above that. A 5,000–6,500 running-watt portable covers this house comfortably — with discipline about what runs simultaneously. A 2,200W inverter generator, by contrast, would mean choosing between the fridge and the furnace blower in January. Size to your worst season, not your best.
The sizing worksheet (fill in yours):
- List every load you refuse to lose (heat? well water? medical device? fridge?)
- Write the running watts from each label (watts = volts × amps if only amps are listed)
- Circle the largest motor load — find its starting watts (label, manual, or ~2-3× running)
- Total running watts + the single largest starting surge = your minimum generator size
- Add 20% headroom — generators are happiest (and last longest) at 50–75% load
Budget generators advertise the biggest surge number in the biggest font. Shop by the running watts, confirm the surge number second, and check the derating fine print: output drops at altitude and in extreme heat, and "maximum" ratings are for minutes, not an outage weekend.
The other 8 chapters are yours for $17
Chapter 1 is free above. The rest — the blunt transfer-switch vs. interlock comparison, inlet & cord sizing, the CO safety rules, the maintenance schedule, and the tape-it-to-the-panel outage checklist — unlocks when you order.
- 🔒 Chapter 2: Generator types: conventional vs. inverter, fuel & noise
- 🔒 Chapter 3: Transfer switch vs. interlock kit: the legal, safe ways in (and why backfeed kills)
- 🔒 Chapter 4: Inlet boxes & cord sizing
- 🔒 Chapter 5: Loads you can — and can't — run
- 🔒 Chapter 6: Carbon monoxide: the chapter that matters most
- 🔒 Chapter 7: Maintenance & storage: the part everyone skips
- 🔒 Chapter 8: The outage playbook: before, during, after
- 🔒 Chapter 9: When to step up to standby
The complete 9-chapter playbook, printable, written from 20+ years in the trade. The right transfer equipment decision protects your family, your linemen, and your wallet. Secure online checkout — instant access after payment.
Buy now — $17Jason answers directly · Licensed PA HIC #PA166735
Need an electrician? Call JS Power LLC.
I'm Jason Mohoska, owner-operator of JS Power LLC (Licensed · PA HIC #PA166735), serving Pittsburgh and Western Pennsylvania. 20+ years in the trade. When you call, you deal directly with me: I quote the job, I do the work, and it's done to code.
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powerjsllc.com · powerjsllc@gmail.com
Licensed Pennsylvania Home Improvement Contractor · PA HIC #PA166735
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