Entertainment event electrical power

Live music and related events needs lots of electrical power to run the audio, video and light systems. Energy is a big costs for a festival. Besides the cost of the electricity itself, there are typically considerable cost of getting enough electricity for a large event and distributing that electricity where it is needed using temporary electrical distribution systems.

Stages use audio, video and lighting These are the most energy-intensive systems, particularly at larger events. Traditionally over half of stage power is used by lighting, traditionally incandescent lamps and later also LEDs that use less power. Bars use electricity for refrigeration, drinks dispensing, audio and lighting. Also both food and nonfood traders at the events need power. Generally electrical power is one of the five single largest production costs for almost any type of music festival.

Electricity use at outdoor events is often provided by diesel-powered generators because in many locations there is no powerful enough electrical feed available for the location. For example music festivals are often situated in fields and countryside, and most of them lack adequate access to a power grid. To use the analogy of a human body for such event, the generators are the heart, the electricity is the lifeblood of a festival, and our power distribution systems are the veins that get it all where it needs to go.

A key issue at outdoor and indoor events is energy security. Power supplies should not fail, and if they do, they need to be corrected quickly. It takes careful planning to make the electrical power reliable. Electricity consumption for specific activities needs to be calculated for the entire duration of the event. It is necessary to choose an appropriate solution based on all factors such as budget, time, space, available resources, the nature of the event and the importance of each aspect of the event. Equipment that is used outdoors (i.e, subject to the elements or ingress from the elements) should have an appropriate IP rating. Also the power system needs to be able to set up and set down quickly, because you typically pay rent for the location and rented equipment.

The electrical power distribution at large uses many different connectors starting from normal mains power outlets to very high current three phase power connections and multi-pin connectors that carry many circuits with one connector.  In many European countries event power is provided on connectors which are known as ‘cee-form’ defined by their current rating. These connectors come in ratings of 16amp, 32amp, 63amp and 125 amp. Single phase (230V) connectors are blue and three phase (230/400V) connectors are red. For power supplies above 125 amps systems such as Powerlock are used and typically provide up to 400 amp three phase. 19Pin Socapex or 16Pin Harting connector is often used to connect many lamps to dimmer with one connector.

Here are some videos on electricity at large events:

Entertainment industry connectors.

Show power distribution. Edinburgh Tattoo.

InfoComm 2014: Applied Electronics Shows Their Power Distro System

InfoComm 2016: Leprecon Showcases Its New LPD Portable Power Distribution Racks

GMS Distribution Power Box Demo

Whirlwind PowerLink UL Listed Tactical Power Distribution Overview

Introduction To Temporary Power

CEP Training Video 1

PCE Merz Portable Power Distribution Box 63Amp 3P+N+E IP67

“The way of earth leakage” by INDU-ELECTRIC Power Distribution

K-LOK 400A Single Pole Connector

Power Connectors – Overview

Stage Left Audio – Power Cords

50 Amp Power Distro – Spider Box for Audio Visual Productions

PCE Mobile Solid-Rubber power distribution boxes – Series STEYR


  1. Tomi Engdahl says:

    Meet The Gaffer #52: Power Distro for a Sitcom Stage

    Set Electrician Sheila Greene takes on a tour of the power distro on a “small” sitcom stage.

    Meet The Gaffer #39: Basic Distro

    In this episode Alan Steinheimer walks through a basic distribution plan for feeding a set with power.

  2. Tomi Engdahl says:


    So you’ve got your rig but how are you going to fire it up? In todays episode we will walk through how we power our large format events. Enjoy.

  3. Tomi Engdahl says:

    LED Screen Installation 01

    Data and Power Cables Connection 02

    Homerun, Feeder Line Cables and Portable Distribution Box Installation pt 3

    380Volts and 220 Connection pt 4

  4. Tomi Engdahl says:

    “The way of earth leakage” by INDU-ELECTRIC Power Distribution

    General Information on earth leakage and how to adjust a RCD with variable settings.

    INDU-ELECTRIC is looking forward to educating our Customer on earth leakage protection and how to field program adjustable RCD / monitors.

  5. Tomi Engdahl says:


    Power Supply Distribution Board. (POWERSAFE) Stage Equipment’s.

  6. Tomi Engdahl says:

    Mini Power Distro “Spider Box”

    Small power Distro “Spider Box” I picked up to use on events where we have the ability to plug up to 30a or 50a circuits so we can power our gear.

  7. Tomi Engdahl says:

    An auxilliary three phase power distribution center we tweaked

    Square D 3phase panel with L21-30 twist loc as well as a considerable amount of 110 circuits, camloc in.

    An auxilliary three phase power distribution center we tweaked 2

  8. Tomi Engdahl says:

    Installing a Temporary Electric Service Pole

    Temporary Electric Service – Home Makercise Power Up

  9. Tomi Engdahl says:

    How to build a temporary electrical service

    E005 – Temporary Power Pole Installation

  10. Tomi Engdahl says:

    Adding 220 Volt Outlets to the Garage

    struggle of not having any 220 volt A/C outlets in your garage space. Same here. The new place we just moved to has only one 220v outlet and it is dedicated to the water heater. This week I am adding in 2 outlets (or “plugs”) to the garage.

    Here’s the plan: Add 2 outlets to the garage; start by running all of the conduit for the wires, mount the plug boxes, pull wire through all the conduit, terminate all of the wires inside the plug boxes, route the wire inside the panel, then finally wire in my breaker.

    Here’s what I’m starting with: I have a large 200 amp service panel inside my garage. This is where the main line comes into the house from the pole.

  11. Tomi Engdahl says:

    “The way of earth leakage” by INDU-ELECTRIC Power Distribution

    General Information on earth leakage and how to adjust a RCD with variable settings.

    INDU-ELECTRIC is looking forward to educating our Customer on earth leakage protection and how to field program adjustable RCD / monitors.

    It will be essential to carefully study and memorize the terminology we are explaining.

  12. Tomi Engdahl says:

    Stage Left Audio – Power Cords

    Electrical extension cords are very important in portable sound systems. Unfortunately, many people (and companies) utilize improperly sized extension cords.

    Relatively speaking, lower gauge extension cords (10ga and less) provide the needed current for amplifiers that are providing bass. Without good current, sound quality will drop. Some amplifiers will temporarily shut off due to low current – this is not good during a show!

    SOOW rated electrical cord should be used. The cord jacketing is very important, especially for where the cord will be utilized.

    The “trick” to good sound… use the largest gauge possible in addition to the shortest distance possible.

    Troubleshoot and Eliminate AC Hum on Sound System

    This video explains common causes and troubleshooting and eliminating techniques for AC Hum on Sound Systems.

  13. Tomi Engdahl says:

    Thermal Remediation Cable and Distribution Box Inspection

    This video will provide an overview of the inspection procedures for Thermal Remediation heater cabling and power distribution boxes. Periodic inspection is to help ensure the product remains in good working order and is safe to use throughout the life of the equipment.

  14. Tomi Engdahl says:

    Pyle PCO 820 Rack Mount Power Distribution Unit – review

  15. Tomi Engdahl says:

    K-LOK 400A Single Pole Connector

    K-LOK 400A single pole power connector is designed for supplying temporary electrical distribution for industry and numerous entertainment applications such as theme park, concerts and TV & movie making. It provides an easy and quick manner to hook up portable power system without special tool.

  16. Tomi Engdahl says:

    AC Pwr Distribution

    Mobile Solar Array AC Power Distribution.

  17. Tomi Engdahl says:

    50 Amp Power Distro – Spider Box for Audio Visual Productions

    Some people on the facebook groups were asking about power distros and I wants to show people what we’ve been using.

    Mini Power Distro “Spider Box”

    Small power Distro “Spider Box” I picked up to use on events where we have the ability to plug up to 30a or 50a circuits so we can power our gear. Coleman Mini X-Treme 01980

    The 4 pole plugs (i.e. 125/250V 50amp) include a line, line, neutral, and ground.

  18. Tomi Engdahl says:

    How Can You Avoid Power Failure?

    fleet of portable power generators offers all the power for our HVAC units as well as all the other power your special event might require. From simple exit signs and basic lighting, to advanced sound and light shows or large quantities of power outlets and expert power distribution projects

  19. Tomi Engdahl says:

    Repair Socapex Multiconnector

    This is a socapex brand multiconnector. Commonly used in the theatrical and concert tour industry to carry multiple power circuits to lights and other equipment. One of the common failure modes of this connector is what we call a spinner. That’s when the pins are no longer locked into place in relationship to the alignment key in the connector.

    If you are running a repair shop, you can save the broken bits of dead connectors as organ donors for other connectors. To replace a burned pin, unsolder the bad pin or socket. This may require unsoldering other wires to get at it. You can now carefully pull apart the two plastic disks that make up the contact disk.

    Take the pin or socket you just removed. Go through your collection of good pins or sockets and find the one that is the exact match. There are different generations of connector and they are subtly different, and incompatible. Put the pin in and solder all the wires back to their appropriate contacts.

  20. Tomi Engdahl says:

    Typical Faults on Distribution Lines

    Typical faults in distribution network
    To gain a broader understanding of power system reliability, it is necessary to understand the root causes of system faults and system failures. A description of major failure modes is provided

    Russian electrical. Epic fail.

  21. Tomi Engdahl says:

    Size Your Extension Cords To Lengths Of The Run
    Voltage Drop And Wire Resistance Factors

    Electrical extension cords are a great way to extend circuits to areas that you are working, away from available outlets.

    But how many extension cords can one tie together and still have the amount of power to power up those tools?

    Is it actually safe to keep adding extension cords to an existing circuit? Well, there are some other factors to consider as well. how many feet from the electrical circuit breaker panel is the outlet that you are connecting to? It could be 50 feet away on the other side of the house. What is size circuit breaker the circuit connected to?

    Many times, the user doesn’t heed the extension cord size compared to the length of the run. They just grab any and all sizes of extension cords and put them together to get to the work at hand. Long runs of wire encounter a variable that you may not have considered, resistance.

    The longer the run of wire, the more resistance, and thus, more heat.

    Voltage drop in the cord often doesn’t allow the power tools to run at full speed. This causes them to heat up and often inflicts damage on them. Wiring inside the tools can melt as well as inflicting damage to the contacts.

    Correct Extension Cord Sizes are Critical to Safety

    The amperage rating for each extension cord should be labeled on a tag attached to each cord, but this label may not always be present or visible.

    Extension cords vary in rating, based upon the amperage they can safely carry and the wattage they can handle—both of which are determined by the gauge of the wire. What’s important when choosing an extension cord is to determine the amount of the wattage and amperage the tool or appliance will draw. With simple devices like lamps, radios, televisions, and other electronics, the familiar basic household extension cord is perfectly acceptable in most cases. Usually, these basic extension cords use 16-gauge wire.

    Extension cords should be rated for loads that are at least equal to, and preferably greater than, the requirements needed to run a tool effectively. Extension cord lengths of 50 feet or less can be used based upon the chart shown below, but runs over 50 feet should implement the next heavier-sized cord to accommodate voltage drop in the cord due to the natural resistance of the wire.

  22. Tomi Engdahl says:

    Problems Using Long Extension Cords

    When you need to use an appliance or a tool in a location too far for the cord to reach, you can utilize an extension cord. That’s what extension cords are for, but they do have their limitations. An undersized cord that’s too long for the job can adversely affect the performance of your heavy-demand tools and appliances and could overheat. In addition, a long extension cord gets in the way, and depending on where you route it, is vulnerable to damage. You can prevent fires and electrical hazards by using a cord rated for the load. Also, remember the recommendation of multiple safety organizations that extension cords are only for temporary use.

    For example, pass 15 amperes of 120-volt current through a 100-foot, 14-gauge extension cord, and the voltage at the end of the cord is only 112 volts.

    The voltage drop through a 12-gauge cord of similar length is slightly less. The final voltage when conducting 15 amps is 115 volts

    In its journey from the plug to your tool or appliance, a long extension cord can pass any number of places where it could get damaged. These places include driveways, walkways, basements, crawl spaces and underneath doors. Cords that pass through a window and down to the ground can also have damage. Even small nicks and gouges that expose the wires in the cord are dangerous. Standing water conducts electricity,

    Always choose a cord rated to handle the load you need it for, and don’t use a longer cord than you need. Route the cord safely and remember to unplug it when it isn’t in use.

    prevent you or anyone in your family or neighborhood from being one of the 4,000 victims of accidents caused yearly by improper extension cord use.

  23. Tomi Engdahl says:


    There are three reasons exension cords are dangerous:
    1. The cable is damaged. Either the isolation or the wires.
    If the current carrying wire is damaged, there will be a higher resistance at that point. Thus a hotspot, probably melting the isolation and shorting it.
    If the earth is damaged, your equipment is not protected against earth faults anymore.
    2. The plug is worn out. Makes your socket burst in flames.
    3. Your using it on full rating when wound up. It will get hot, and melt. This is probably the most common cause of extension cords malfunctions. Apart from people cutting it with a garden trimmer.

    Some appliances can be damaged by sustained undervoltage. e.g. anything with a switched mode PSU will typically draw more current at lower voltages, and anything with a high power motor is more likely to stall, and may overheat if its fan cooled. However with a little common sense, nearly anything can be run at the far end of a good quality 100′ lead without significant problems

    If it is low quality and made from too small wire (did I just broke my signature) it adds a lots of resistance between the safety fuse and the device you are using. If everything goes as it should NOT to go, you have a short circuit that will not trip the fuse quick enough and the permanent wiring in your house will melt in worst case.

    The longer the extension lead, the higher the voltage drop, leaving less voltage for the appliance. Many loads such as switched mode power supplies and induction motors actually draw more current, as the voltage is increased.

    Another issue is safety. As mentioned above, the extension lead should not be coiled up and used at its full rating. It’s also susceptible to damage. Another problem is the increased resistance of the earth conductor. If a phase to earth fault occurs, the voltage on the earth conductor needs to remain below 50V (to avoid the risk of shock) and blow the breaker fast enough to avoid fire. If the extension lead is too long, then the earth conductor’s voltage can rise to an unsafe level, under fault conditions and the breaker might not trip in time to avoid a fire. Fortunately if you’re using an RCD/GFCI then it will trip before the earth conductor’s voltage becomes dangerous but a phase to neutral short could still cause a fire, if the breaker doesn’t trip in time.

    To mitigate the above problems, the longer the extension lead is, the thicker the cable needs to be.

    The extension cord should not be getting noticeably warm.

    10awg is rated for 15A power transmission. Its resistance is 1ohm per 1000ft, which is 0.1ohm for an 100ft extension cord, or a little less for an 80ft industrial length (this is a common reel size). 15A rms * 0.1ohm = 1.5V rms drop and ~25W dissipated

    The entire problem is voltage drop caused by wire resistance. About the biggest extension cord you can get is #12 AWG and it will probably work fine for your 15A welder out to 100 ft. Probably… Not guaranteed… When you start stacking two extension cords, things might get a little iffy at 200 ft.

    The breaker should trip at 10x nominal so a 20A breaker should trip at 200A instantaneously. Every other kind of trip is ‘long time’ and has to do with long time overcurrent. Possible, but not likely. So, the question is, could you have enough resistance to preclude creating a 200A short circuit. 120V / 200A = 0.6 Ohms down and back and, as luck would have it, the resistance is 0.685 Ohms for #12 AWG. There is a slight possibility that a short circuit won’t trip the breaker. But it will trip pretty soon on ‘long time’.


  24. Tomi Engdahl says:

    How to Pick an Extension Cord – Extension Cord Safety

    There are thousands of fires and injuries caused by extension cords every year. When picking an extension cord for a project, the most important thing to know is how much current is being used and the rating of the extension cord.

  25. Tomi Engdahl says:


  26. Tomi Engdahl says:

    100ft 10/4 AWG Generator Cord Voltage drop test

    Checking voltage drop of my new 100 foot Generator Extension Cord from eBay and Coleman 3-Foot Generator Power Cord Adapter from Amazon.

    No load – 120 V

    Lights connected directly to generator – 119 V

    Lights connected via Extension Cord & Adapter – 117.5 V

  27. Tomi Engdahl says:

    Are RV dog bones (30 to 15 amp adapters) safe?

    I noticed my extension cord was pretty warm and had to check how much power I was using. Good thing I caught it in time.


    I connected my 50 amp shore power line to a 30 amp dog bone to a 15 amp plug and plugged it into a household extension cord. The extension cord was left coiled up. I thought the motorhome was drawing about 6.5 amps, but obviously it kicked way up and set the extension cord on fire

  28. Tomi Engdahl says:

    You’re using your Extension Cord Reel wrong!

    Extension cord reels, or rolly cords as I like to call them, are seriously handy. Nobody likes spending 30 minutes untangling a 50m extension cord.

    Trouble is, usually we use them incorrectly.

    It turns out you have to read the fine print: You can only use the full capacity of the reel if you fully unwind the rolly cord.

    If you don’t fully unwind the cord, the power rating of the reel drops by a factor of 3, which means the current you can draw drops by a factor of 3, which means you’re likely to destroy the poor thing!

    Rolly cords have (usually) thermal circuit breakers, but those breakers are a) cheap, and b) designed to trip at the max current for the reel when the cord is fully unwound.

    Technically, this is “overheat protection”, but in my experience it doesn’t work well at all when the cord is still on the reel – even with premium brand reels.

  29. Tomi Engdahl says:

    How-To avoid extension cord overload

    What happens when you overload an RV extension cord.

  30. Tomi Engdahl says:

    All About Paralleling Generators, Reviewing Multiple Parallel Kits & Gen Sets, 50 amp & 30 amp Cords

    When it comes to paralleling generators there are many setups and kits available. Will you need 30amp or 50amp receptacles?

    Paralleling Generators, Running Generators in Parallel

    Paralleling generators or running generator in parallel, simply put is; connecting two generators (often of same brand and size) together to provide double the power.

    Why not just buy a larger generator?
    There are several reasons why someone may not want to simply “buy a larger generator.” The most common reason is when someone already owns a particular inverter generator and then discovers later they need a little more power supply. This is when it makes sense to purchase an additional generator to accommodate the added power needs rather than abandoning their current setup. Furthermore, inverter generators are more fuel efficient and significantly quieter than a comparable sized open frame generator.

    Does Paralleling Cause Damage to Generators?
    Running parallel generators is not a problem as long as they are two generators that are designed to be run in this way. Furthermore, most generators require a particular parallel cable to make this work. The reason for this is that each generator has its own computer inside. They are not designed to work well together among different manufacturers. This synchronization is often only possible if the manufacturers are the same.

    It is very important to carefully select the correct parallel kit. Each manufacturer has different requirements and capacities.

  31. Tomi Engdahl says:

    How to operate two generators in parallel

    In this video, I will demonstrate how to parallel two MEP-002A diesel generators. Operating the generators this way provides for double the power output of a single generator, and allows them to handle significantly larger starting surges.


    this is a job well done, great demonstration.

    This is an excellent video that simply explains how paralleling is accomplished. I’ve worked on generators and paralleling for more than 30 years and this video is perhaps the best one I have seen on the subject. Also loved the old Onan-powered military units running together…haven’t seen that before.

  32. Tomi Engdahl says:

    Synchronizing AC generators — Part 1 (introduction and sync lamps)

    We are using a pair of Delco-Remy 3-phase alternators to generate 60 Hz AC power for a miniature demonstration electrical power grid. In this video, we discuss some of the details of generator synchronization.

    Synchronizing AC generators — Part 2 (strobe light view)

    We are using a pair of Delco-Remy 3-phase alternators to generate 60 Hz AC power for a miniature demonstration electrical power grid. In this video, we discuss some of the details of generator synchronization, using a stroboscope to prove two generators are spinning in-phase with each other.

    Synchronizing AC generators — Part 3 (sync and unsync)

    We are using a pair of Delco-Remy 3-phase alternators to generate 60 Hz AC power for a miniature demonstration electrical power grid. In this video, we demonstrate how two generators may be synchronized with each other, then unsynchronized, then synchronized again.

    Synchronizing AC generators — Part 4 (phase deviation)

    We are using a pair of Delco-Remy 3-phase alternators to generate 60 Hz AC power for a miniature demonstration electrical power grid. In this video, we demonstrate how two generators may be synchronized with each other, then “stressed” by running their prime movers at different torque values to show how a phase shift develops between the two machines.

  33. Tomi Engdahl says:

    Diesel generators synchronizing with mains

    Diesel generators synchronizing with mains on ”peak lopping mode” and on ”nobreak transfer mode”

  34. Tomi Engdahl says:

    Paralleling Generators

    This video explains paralleling generators, the basic operation and the merits of a parallel generator system.

  35. Tomi Engdahl says:

    Power Distribution
    An absolutely vital but often overlooked aspect of system form and function.

    Whether it’s a large festival line array rig or a single loudspeaker on a stick, all audio systems have one thing in common and that’s a need for power. Before starting to design, build, or use any power distribution equipment, the local laws and electric code should be consulted.

    it’s important to check with a local government’s electrical inspectors and ascertain their specific code requirements. Once you’re up on the local codes it’s time to get the juice flowing to the gear.

    Checking Things Over
    The most basic way of getting power to equipment is plugging into a wall outlet at the venue. But this can have consequences if you don’t take the time to check out the outlets and breakers before the gig. The most common problem with wall outlets is that multiple outlets are allowed to be wired into a single breaker, and somebody else can plug into the same circuit as your gear and overload the circuit.

    Before using any outlets in a venue, ask the venue staff if they’re relying on any of them during the event. Even plugging in a coffee pot to one of the circuits has the potential to wreak havoc with a system. Also check with the event planner to see if any other vendors, such as a photographer or videographer, will need power.

    Next, find out what outlets in the venue share a breaker. This is easily accomplished by using a circuit breaker locator.

    Using a circuit breaker locator is much more convenient than flipping breakers trying to locate an outlet because you won’t inadvertently turn off something important.

    Once you’ve identified which outlets are on what circuits, label the outlets and the breaker box so it can be easily reset if a breaker is tripped later. After identifying the outlets that share a circuit, put a piece of gaff tape over any extra outlets to keep others from plugging into them. I find that a piece of white or yellow gaff with the words “Do Not Use” placed over the outlet keeps most from pulling off the tape and plugging in.

    While locating breakers, also test to find out if the outlets are wired correctly. Most folks are familiar with the basic three light “cube” testers that plug into an outlet and can indicate different wiring problems via the three onboard lights. These testers can tell if an outlet is working and if it has a ground, but they cannot tell if an outlet is wired incorrectly with a “Reverse Polarity Bootleg Ground” (RPBG), which can be dangerous.

    Plug Configurations
    Speaking of extension cords, there are a variety of portable power cables used in show business, normally described by their connector type.

    By the way, use only 12 AWG extension cords at gigs. Voltage drop occurs when running longer power cords, and this effect is more pronounced the longer the cable, and the smaller the wire gauge.

    Feeder cables are single conductor runs that consist of a Ground wire, at least one Neutral wire, and one, or more commonly two or three, Hot wires. Feeder cables tie into a generator or Company Panel Disconnect and provide power to a Portable Power Distribution System (a.k.a., PD). These systems are commonly single phase (two Hot wires) or three phase (three Hot wires).

    The NEC says that single conductor supply cables cannot be smaller than 2 AWG and any ground conductor cannot be smaller than 6 AWG.

    The connector for Feeder cables is called a Cam Lock. They can handle 400 amps at 600 volts.

    Concerning Feeder cable, the NEC states: “Only Qualified Personnel may route, connect, energize or de-energize supply services.”

    Electrical accidents are estimated to rank sixth among all causes of work-related deaths in the U.S. and are disproportionately fatal compared to other work-related accident types.

    The branch circuits may include Edison outlets, Twist Lock outlets (popular for equipment that needs more than one Hot conductor) or even multi conductor 6-circuit 19-pin connectors (a.k.a., SOCAPEX, SOCA, or VEAM) that can be used with a multi cable and provide multiple circuits to one location.

    SOCA cables are commonly used to provide six circuits of AC to self-powered line arrays. A fan-out converts the multi-pin into individual circuits or power.

    Wrapping It Up
    Speaking of generators, never use general construction types for production equipment. We require generators that run at a constant voltage and stable frequency while producing as little noise as possible. These type of units are known as “production,” “show,” “entertainment,” “quiet,” or “whisper” generators, and have excellent voltage regulation, usually within 1.5-percent tolerances or better.

    Standard construction type generators are usually not as reliable as show types, and are often quite unstable. (By as much as 25 percent.) This may be O.K. for running power tools on construction sites, but not very good for sensitive electronics like audio equipment.

    Finally, check all power distribution system components before use, and perform preventive maintenance on cables, connectors and components a few times a year.

    If an item is damaged at a show, pull it from service until it can be correctly repaired. Treat electricity with the respect it deserves and the gig will go much more smoothly – and no one gets hurt.

  36. Tomi Engdahl says:

    Power & Electrical Safety On Stage

    Staying safe on stage is more than a matter of simply making sure that willing hands are available before taking a dive. Knowing how to properly handle the mains power we all need is also crucial to performance health…

    Whatever the size, complexity or cost of your live sound rig, one of the first — if not the first — question on your mind when you get to a venue will usually be “where do I plug it in?” Depending on the venue, the answer can vary from a wall-socket behind a plant pot to a dedicated and professionally-installed supply that is reserved for your exclusive use, fully tested and certificated, and for which (with any luck) you’ll have brought an appropriate connector. Whatever you encounter, you’ll need to know some basic rules. When it comes to portable live-sound systems, this means firstly, using a suitable electrical supply; secondly, using suitable equipment; and, thirdly, connecting and using that equipment safely.

  37. Tomi Engdahl says:


    Today we are here to talk about household distribution. In a home, it’s very important to understand the etiquette of breakers, circuit boxes, and your power needs.

    The first thing you’ll want to do is make a map of the place. You can’t just plug lights in anywhere you want because you’ll very quickly overload household circuits. The best way to make a map is by flipping breakers on and off.

    Quick Tip: If your household breakers aren’t already labelled at your location, do so. Label each breaker according to it’s location. For example, “Kitchen” or “Garage/Basement.”
    This will save you time on the day when a breaker trips and you need to figure out which circuit it’s on. Labeling them will tell you exactly which one(s) switched off.
    Household circuits are generally only 15-20 amps and, in total, you usually only have anywhere from 60-100 amps in the entire house.

    There are 220V plugs on dryers. They are similar to our genny connectors here. The dryer connectors have 4 prongs on them. You have a ground and a neutral and then a hot and a hot. You do need to build an adaptor that eliminates one of the hots. You separate the hots out so you have 2 hot connectors on the end of that. That way, you can access all 30 amps.

  38. Tomi Engdahl says:


    This article is directed towards lay people to enable them to easily understand it.

    Generally speaking event power is provided on connectors which are known as ‘cee-form’, ‘commando sockets’ or defined by their current rating. These connectors come in ratings of 16amp, 32amp, 63amp and 125 amp. Single phase connectors are blue and three phase connectors are red. If a power supply is defined by a current rating that is not one of these numbers then the reliability of that information should be questioned.

    For power supplies above 125 amps systems such as Powerlock are used and typically provide up to 400 amp three phase (1200 amps total). Â This type of equipment is very specialist and only used for projects where very large amounts of power are being used such as arena concerts and large marquee events.

    Breakers work in the same way as a fuse

    An RCD is probably the single most important safety device in an electrical system. RCD stands for Residual Current Device and will ‘trip’ in the same way as a breaker when triggered.

    RCDs and breakers are often combined into the same unit.

    Earthing is another very important safety function within power and it also plays a unique role with audio equipment.

    Often the cable route from appliance to ground can be very long and contains a great deal of resistance. For this reason we conduct a routine called “earth impedance testing” which measures to ensure the route to ground is good. This is an essential part of the ‘sign off’ process once equipment has been installed.

    A competent power contractor will provide an installation sign off upon completion of their work. This is an important process and acquiring this documentation is vital for an Event Manager.

    The process checks that each area has been installed correctly in a formulated and thorough checklist approach. The signature states that all equipment has been installed properly and safely.

    PAT stands for Portable Appliance Testing. This is an annual test procedure that should be carried out on all equipment that distributes or uses electricity. This applies to all electrical items both at events and in commercial environments such as offices or warehouses.

  39. Tomi Engdahl says:

    Wye vs Delta ( A brief overview)

    In Russian they call the wye a “star” and the delta a “triangle”.

    How the delta 3 phase system works

    This one covers the wiring of the the delta 3 phase system. This video is part of the heating and cooling series of training videos

  40. Tomi Engdahl says:

    Entertainment industry 400A powersafe connectors.

    A look at some of the Powersafe powerlock-style connectors used for connecting high current supplies in the entertainment industry, temporary power industry and various industrial applications including factories and quarries. They allow suitably trained individuals to make a very fast high current connection easily and safely.

    The Powerlock style connector replaced the older Camlock connector which was similar to a welding connector and had a very open construction with exposed live metal on both the plug and socket. The new style has fully shrouded connections, keying to avoid misconnection and a locking pin to prevent accidental detachment.

    They can be terminated either using the set-screw clamping as shown, with various reducing sleeves for smaller cables, or a version is available that can be crimped on. Once assembled and mated they are well protected against ingress of water and dirt.


    It says so very obviously on the sticker, but maybe it’s worth mentioning that they are designed to CARRY a huge load, but not to BREAK a huge load. If you disconnect these under load, you might draw an arc, and that might heavily injure you, kill you, or set you and the entire place on fire. At the very least it will scare you shitless :)

    They should only be mated and parted off-load, but it’s better to assume the worst. Particularly in an industry like the event industry which relies heavily on the Dunning Kruger effect.

  41. Tomi Engdahl says:

    Phase 3 Connectors Ltd – Powersafe Single Pole Connectors

    Phase 3’s Powersafe range are the highest rated, safest and finest quality single pole connectors as used by the power, events, military and cable assembly industries worldwide.

    Powersafe are the industry’s safest high current powerlock type connectors. The UL Listed power connectors are rated up to 800 amps and are perfect to mate with the Powersafe Box.

  42. Tomi Engdahl says:

    Electric Panel and power distribution basics

    A video explaining how electric breaker panels work and how they are configured. These panels can be found anywhere from your house to large building and are actually quite simple but can be intimidating to someone who has never worked on them before. I explain how they are wired and what to be careful of when working on these panels live.

  43. Tomi Engdahl says:

    600v dead short

    600V is a standard voltage in Canada…. The U.S uses ” 277/480V, for commercial / industrial lighting and power, we use ” 347/600V”.

    600 volts is industrial voltage in (some) countries that have 230v on their normal sockets at home.

    230v (or 240v) 3 phase is roughly 400v. 600v 3 phase to me would be a phase voltage of 350 (approx)

    Most big motors I know here have 3 phase (400v – 230v phase voltage) with big invertors etc.

  44. Tomi Engdahl says:

    Dangers of arc flash

    In this video, Fluke presents common dangers associated with arc flash, as well as what to watch for.

    480 volt 3-phase Arc Flash Demonstration

    Here arcs were intentionally initiated by bridging wires across three copper bus bars in a testing laboratory. Three phase 480 volt power was then applied across the bus bars for about 1 second. The wires immediately explode, forming a conductive plasma which forms high current power arcs between phases. The actual fault current in the demonstration is not known, but is likely in the range of tens of kiloamps.


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