Film Set Power & Distro: A Practical Planning Guide

A field reference from Lightbulb Rentals. Bookmark it, share it with your gaffer, and use it to plan power before you ever load the truck.

Running out of power mid-setup is one of the most avoidable ways to lose an hour on set. Whether you’re lighting a corporate interview in an office or a music video in a warehouse, a few minutes of math up front tells you exactly what your location can handle — and when you need a generator or a tie-in. This guide walks through the numbers, the gear, and the safety basics in plain language.

Safety note: This is planning guidance, not an electrician’s manual. Anything involving a tie-in to a building’s electrical panel, high-amperage distribution, or a generator over ~10kW should be handled by a licensed electrician or an experienced gaffer/best boy. When in doubt, hire the qualified person — it’s cheaper than a fire.

The only three numbers you need: watts, volts, amps

North American wall power is 120 volts (V). Every fixture draws a certain number of watts (W). What actually trips breakers is amps (A). They relate by one simple formula:

Watts = Volts × Amps → so Amps = Watts ÷ 120

That’s the whole game. If you know how many watts your lighting package pulls, you know how many amps you need — and whether a given outlet can feed it.

What a normal outlet can actually give you

Most wall outlets are on either a 15-amp or 20-amp circuit (check the breaker in the panel — 20A circuits often have a T-shaped outlet slot). But you should never plan to the maximum. Electrical code and common sense use the 80% continuous-load rule: only load a circuit to 80% of its rating for anything running more than a few minutes.

Circuit	Max (theoretical)	Safe continuous load (80%)
15 A @ 120V	1,800 W	~1,440 W
20 A @ 120V	2,400 W	~1,920 W

The other trap: several outlets in a room are often on the same circuit. Plugging into three different wall outlets doesn’t help if they all run back to one 15A breaker. When you can, spread heavy loads across circuits you’ve confirmed are separate.

Approximate draw of common fixtures

Use this to ballpark a package. Always confirm the actual draw on the unit’s label or ballast — wattage varies by mode, and HMI/tungsten inrush at startup can spike well above the running figure.

Fixture (typical)	Approx. max draw	Approx. amps @120V
Aputure LS 300x	~350 W	~2.9 A
Aputure LS 600x Pro	~720 W	~6.0 A
Aputure LS 1200d Pro	~1,440 W	~12.0 A
ARRI SkyPanel S60-C	~420 W	~3.5 A
LiteMat 4 (via ballast)	~450 W	~3.8 A
Astera Titan Tube (each)	~72 W	~0.6 A
650W tungsten fresnel	~650 W	~5.4 A
1K tungsten	~1,000 W	~8.3 A
2K tungsten	~2,000 W	~16.7 A
1.2K HMI (w/ ballast)	~1,500–1,800 W	~12.5–15 A
M18 HMI (w/ ballast)	~1,800–2,200 W	~15–18 A

A quick read of this table shows why modern LED packages are so location-friendly: a couple of Aputure 600x units and some tubes will happily live on ordinary house power, while a single 2K tungsten or M18 HMI can eat an entire 15A circuit by itself.

How to size your power in four steps

1. List every fixture you plan to run at the same time and add up the watts. Include anything else on the same power: monitors, chargers, a haze machine, video village.
2. Add ~20% headroom for startup surges and the odd extra draw. (Peak watts × 1.2.)
3. Divide by 120 to get total amps.
4. Compare to what the location gives you. Each confirmed 15A circuit = ~1,440W usable; each 20A = ~1,920W. If your total exceeds the available circuits, you either redistribute, swap to lower-draw fixtures, or bring your own power.

Worked example: two Aputure 600x (720W each = 1,440W) + four Astera tubes (~290W) + a monitor and chargers (~200W) ≈ 1,930W. Add 20% ≈ 2,320W ≈ ~19 amps. That won’t fit on one 15A circuit, but it splits comfortably across two — or lives on a single 20A run with a little care.

House power vs. generator vs. tie-in

• House / location power — free and simple for LED-forward packages under a couple thousand watts. Map the circuits first; don’t assume.
• Portable generator (“putt-putt”) — a quiet inverter generator (2–7kW) covers most small runs when outlets are scarce or you’re outdoors. Size it the same way: sum your peak watts, add headroom, and don’t run it near max.
• Towable generator + tie-in — for larger HMI/tungsten packages. This is licensed-electrician territory: proper distribution, grounding, and cable protection are non-negotiable.

Distribution gear, briefly

• Edison — the standard household plug. Fine for lighter loads.
• Bates / stage-pin — the film-world workhorse connector for 20A and 60A distribution; more secure and rated for set use.
• Stringers & distro boxes — extension cable and breakout boxes that let you run power from the source to where you need it, split across protected circuits.
• Cam-Lok — high-amperage single-conductor connectors used from generators/tie-ins into distribution.

Match connectors and cable gauge to your amperage, keep runs as short as practical to limit voltage drop, protect cable in walkways, and keep power away from water.

Safety checklist

• Confirm which outlets share a circuit before you load them.
• Stay at or under 80% of each circuit’s rating.
• Use GFCI protection near any moisture; keep connections dry.
• Don’t daisy-chain power strips to dodge the math — that’s how breakers (and worse) go.
• For tie-ins, towable generators, or anything you’re unsure about, bring in a licensed electrician or a qualified gaffer.

Figures are typical approximations for planning only; always verify the actual draw printed on each fixture and consult a qualified electrician for tie-ins and high-amperage distribution.