Lighting: Maximum amount of watts you can run off a UK household power socket...

[Dave Draper]

A hypothetical situation, but something I've wondered for a while...

If a scene requires multiple high powered lights, but you don't have access to a genny, or it doesn't fall within the budget; what is the maximum amount of watts you can run off a UK household power socket before something either goes pop, or doesn't work at all? Or is the electricity bill the only thing you'd need to worry about?

DD.

 

[Samir Patel]

Curious about this in the US as well.

 

[Liam Hall]

Obviously, it depends what else is plugged into the circuit, but usually circuits are 13amps, so don't go above 3000 watts. Anything more powerful then you absolutely need a gaffer.

 

[Samir Patel]

Thanks Liam. I'm a noob when it comes to lighting so I was just worried about plugging these Arri 650W lights into a home electrical outlet (they seem to be a good cheap light to start out with).

 

[Bob Gundu]

Thanks Liam. I'm a noob when it comes to lighting so I was just worried about plugging these Arri 650W lights into a home electrical outlet (they seem to be a good cheap light to start out with).

No worries at all with those lights.

 

[Antony Newman]

Power = Volts x Amps.

Standard UK electrical sockets have 13Amp fuses / 240 volts
Standard US electrical sockets have 15Amp fuses / 120 volts (Amended)

Power from an individual UK socket = 13A x 240V = 3120 Watts
Power from an individual US socket = 15A x 120V = 1800 Watts (Amended)

AJ

 

[Marc Wielage]

My observation is that you need a gaffer anyway, just to avoid getting into a world of hurt.

 

[Peter Mosiman]

Damn I wish the US ran off of 240v

 

[Zeb B]

USA
Residential: 15A x 120V = 1800W
Commercial (with the funny sideways "T" slot): 20A x 120V = 2400W

Anywhere else in the world: V x A = W

Figure 80% utilization to avoid circuit breaker trips caused by current inrush. Always find the circuit breaker panel box and specific breaker before plugging in to avoid disruption to production if things start popping.

Use LED's and other low wattage light sources.

EZ Breezy

 

[David Kuhn]

The sideways slot 20A socket in the US does not guarantee that the circuit supports 20A (I see those sockets quite a lot, sometimes they're incorrectly wired to 15A breakers)... but it at least means there's a chance.

20A extension cords are EXPENSIVE.

 

[Ulf Krentz]

Also keep in mind HMI lights, especially those without active line filter / power factor correction may have a higher current draw as well. Best to have a gaffer or at least split your power over multiple breakers by using outlets from different rooms, floors etc. The time spent on checking these things before production will pay back anytime.

 

[Michael Bernstein]

Wandering across the pond. Some of the rules of thumb still apply. Don't they?

In the US, it's (commonly) 15A per circuit in the home.

You may have more than one outlet per circuit. So just because there's another plug doesn't mean there's more power.

In some basements, home shops, and other semi-industrial settings: quad boxes (four-outlet boxes) may carry two circuits. If you're reduced to guessing, plug on the diagonal to increase the likelihood of getting distinct circuits.

Better still: If you can flip breakers off and on, you can discover which breaker corresponds to which outlet(s). (Of course you'll have to have a test load plugged into every outlet under test.)

Breakers generally indicate their rated load. It's far more trustworthy than socket shape.

Circuits installed for air conditioners, stoves, and washing machines may have dedicated (and higher-rated) circuit breakers.

If a load keeps tripping a breaker, take some of the load (some of the lights) out of the circuit.

Watch out for intermittent loads that somehow share your lighting circuit: loads like hairdryers, microwaves, refrigerators, washing machines, electric ovens, and portable heaters.

Michael