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Frequently Asked Questions

Straight answers about voltage, sizing, equipment, and what PowerCheck does (and doesn't) do. If your question isn't here, send it to us and we'll add it.

In short

PowerCheck sizes single-phase 120V / 240V split-phase battery systems for food trucks. We do not size 3-phase, we do not recommend generator + transformer workarounds, and we only recommend inverters that can deliver the voltages your equipment actually needs.

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Voltage & Phase

120V, 240V, split-phase, and why 3-phase doesn't fit a food truck.

Does PowerCheck support 3-phase power?

No. PowerCheck is built for single-phase 120V / 240V split-phase only — the same residential service every off-grid food truck inverter on the market is designed to deliver.

3-phase (208V or 480V) shows up in commercial kitchens, commissaries, and industrial buildings. It does not appear on food trucks because:

  • No mainstream off-grid inverter brand makes a true 3-phase unit at food-truck scale and price.
  • 3-phase equipment costs more, weighs more, and almost no food-truck-specific appliance is sold in 3-phase.
  • Shore power at events and commissaries is overwhelmingly single-phase 120/240V.
If your equipment is 3-phase, PowerCheck can't size a battery system for it. Talk to a licensed electrical contractor about a single-phase replacement for that piece of equipment or a dedicated commercial install.

What is split-phase 120/240V and why does it matter?

Split-phase is the standard residential service in North America. One inverter outputs two 120V "legs" 180° out of phase, which gives you 240V between the legs and 120V from either leg to neutral. One box, two voltages.

Why it matters for food trucks: every truck has 120V loads (POS, fridge, lights, water pump) and often one or two 240V loads (large griddle, espresso machine, electric fryer). A true split-phase inverter serves both from a single neutral — no extra hardware needed.

What PowerCheck recommends: when your equipment list contains any 240V item, we only show inverters whose nameplate output is "120/240V split-phase" — verified single-unit or in a manufacturer-supported parallel configuration.

Why isn't the Growatt SPF 5000US recommended when I have a 240V load?

The Growatt SPF 5000US is a 240V single-phase inverter — it outputs 240V only, with no 120V leg. Even paralleling multiple Growatts (the manual lists single-phase and 3-phase parallel modes) does not produce split-phase output.

Because every food truck also runs 120V loads, a Growatt-only build would leave the POS, fridge, and lights without power unless you add an external auto-transformer. PowerCheck's policy is to not recommend transformer-based workarounds — they add cost, weight, heat, and another failure point inside a moving vehicle.

When Growatt IS a good fit: all-120V trucks where the inverter's 240V output is simply unused. In that case, the calculator will still surface it.

Why did the calculator switch my item to 240V automatically?

Some pieces of food-truck equipment draw more wattage than a standard 120V / 20A circuit can legally carry. NEC limits a continuous load to 80% of the breaker rating, which works out to 1,920W on a 20A / 120V circuit.

If your item's nameplate draw exceeds 1,920W, the calculator auto-flips it to 240V and shows a small "auto 240V" badge. You can still toggle it back to 120V manually if your truck is wired for higher-amperage 120V circuits, but the default protects most installs from undersizing wire and breakers.

Can I force an item to 120V or 240V manually?

Yes. On the Step 9 equipment-review table, every row has a Voltage toggle. Use it when you know the nameplate better than our default — for example, an espresso machine sold in both a 120V and 240V SKU. The calculator uses the voltage you select for both the inverter-eligibility check and the recommended-system filter.

Sizing & Calculations

How PowerCheck arrives at battery kWh, inverter watts, and the price you see.

How do you size the inverter?

Plate sum × 1.0. We add up the running watts of every item on your equipment list and recommend an inverter whose continuous rating covers that sum. We do not add a separate surge or safety multiplier on top — modern inverters already publish their own surge headroom, and we filter the recommendations against your equipment's actual peak draw.

How do you size the battery?

We multiply each item's running watts by a per-item duty cycle (how often it's actually drawing during the shift), then sum across your shift length to get watt-hours. By default we use 100% depth of discharge (DoD) for LiFePO4 — that's the standard the chemistry is rated for. An optional 80/20 longevity setting is available if you want to extend cycle life.

What is the 10% install uplift on the recommendation price?

The system price you see is battery + inverter + 10%. That 10% is a flat allowance for the parts you'll buy regardless of vendor: wire, lugs, breakers, fuses, busbars, mounting brackets, and a battery enclosure. It's broken out as its own line on the result card so you can see equipment-only vs. installed total.

It is not labor. Pro install labor varies too widely by region and truck layout for us to estimate.

What do "Most Affordable", "Best Balance", and "Most Rugged" mean?

For each vendor (Signature Solar and BigBattery), we show up to three valid configurations:

  • Most Affordable — lowest total system price that still meets your spec.
  • Best Balance — the lowest-priced option that uses a single inverter (no parallel build). Cleaner install, fewer connections to maintain.
  • Most Rugged — the highest-headroom option within ~1.5× the affordable price. More surge margin, more battery kWh.

All three are valid systems — pick the trade-off that matches your build budget and tolerance for parallel complexity.

Equipment

What we know about your gear, what we don't, and how to fill the gaps.

My equipment isn't in your database. What do I do?

Use the Custom Item picker. You'll enter the nameplate watts (and optionally duty cycle and voltage), and the calculator treats it identically to a known item. The simpler path: type the brand and model into the search box — even if we don't have a stored profile, we'll often resolve it from the model number.

What is "duty cycle" and why does it matter so much?

Duty cycle is the percentage of an hour your equipment is actually drawing power. A refrigerator with a 400W compressor doesn't draw 400W for 60 minutes every hour — it cycles. In real service it's pulling 400W for roughly 33% of the time, so its real-world load is ~133W average.

Getting duty cycles right is the difference between a battery sized for the nameplate (massively oversized) and one sized for reality. PowerCheck ships with a duty-cycle database calibrated against real food-truck installs.

Should I convert my propane equipment to electric?

Usually no. Any single load above ~3kW (electric griddles, electric fryers, large char broilers) drives battery and inverter cost up steeply. If propane is already on the truck, keeping the high-heat cooking on propane and reserving electricity for refrigeration, lighting, POS, and small appliances is almost always the cheaper, lighter, more reliable build.

When the calculator detects an item over 3kW we surface a propane advisory next to it.

Using the Calculator

Tips, gotchas, and what changed in the latest build.

Can I upload my equipment list as a PDF?

Yes. Drop a vendor invoice, an equipment spec sheet, or a build sheet into the upload step and the AI will extract every powered item it can identify, with watts and (where available) voltage. You can edit anything after extraction.

Can I save my spec and come back to it?

Yes. After you generate a recommendation, you can save it as a shareable spec page. We'll email you a link to your spec — that's also how the calculator stays free: no account, no password.

Buying a System

Vendors, sourcing, and what's actually on the cards.

Why do you only show Signature Solar and BigBattery?

They're the two off-grid vendors we've vetted with a complete product line that fits food trucks: LiFePO4 server-rack batteries plus single-phase or split-phase inverters in the 3kW–18kW range, with full certification paperwork (UL 1973, UL 1741, UL 9540). We'll add more vendors as we vet them — if you'd like us to evaluate one, let us know.

Are these affiliate links?

Some are or will be. Affiliate revenue is how the calculator stays free. We do not change which inverter or battery the engine recommends based on commission — the engine picks the cheapest valid system that meets your spec, full stop. If a vendor we don't have an affiliate relationship with is cheaper, you'll see them.

Safety & Certifications

What certifications you actually need.

What certifications should a food truck battery have?

Four required, one optional:

  • UN 38.3 — transportation safety (shipping the battery)
  • UL 1973 — battery-system safety
  • UL 1741 — inverter safety
  • UL 9540 — complete energy storage system safety
  • UL 9540A — fire-propagation testing (optional, sometimes required by fire marshals)

Full deep-dive: see the Certifications page.

Do I need a licensed electrician to install this?

For anything above ~2kW of inverter, yes — strongly recommended. The wiring, breakers, and grounding inside a moving vehicle that serves the public are not a place to learn on the job. Many jurisdictions also require a permitted install before a fire marshal will sign off on the truck.

Don't see your question?

Email us and we'll answer directly — and add common questions to this page.

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Related Reading

If you found this helpful, these next pages go one layer deeper.

Battery vs Generator: 5-Year Math →
The detailed cost breakdown most owners skip.
Choosing a LiFePO4 Battery →
How to read a battery spec sheet without getting fooled.
Installation & Wiring →
Cable sizing, shore power, and inverter mounting.
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