Power is the key to everything we do, and we rely on different forms of power distribution. Starting at the top, some of the higher-end cables and supplies we don’t actually have or use, but are included here for completeness.
Power is supplied to most high-usage buildings in a three-phase supply, with each phase 120 degrees shifted from the others. This means that while power is being drawn from one phase, it is being returned down the other two phases – the neutral cable should be unnecessary! However, in practice this only happens when the load across all three phases is evenly balanced, and so a small amount of current is expected down the neutral.
The voltage between one phase and neutral is the standard 230V, but as the different phases are 120 degrees out of phase, it is possible to get a potential difference of around 400V between phases. It’s important to make sure that you don’t accidentally connect equipment across multiple phases, unless it was designed to handle it (such as dimmer packs).
Powerlock (200 – 600A)
Powerlock is used for high-power connections, one connector is used for each phase (L1, L2, L3) of the supply, plus one for neutral (N) and one for earth (E). We don’t deal with this ourselves, but it’s commonly found on large dimmer racks, and sometimes as the main supply for a building or venue.
The CEEform (IEC60309) connector group is a range of colour-coded connectors used for many different voltages and varying currents, as well as three-phase + neutral, and three-phase without neutral (used for some motors). We use a lot of different CEEform connectors here.
The idea is that the colour-coding indicates the voltage carried by the connector, with red being about 380-480V, blue about 200-250V, and yellow about 100-130V. However, at the union we use the yellow CEEforms to indicate dimmed power, so those found on our rig will run 230V.
125A TPNE CEEform
This is the largest common CEEform in use in the entertainments industry, a three-phase + neutral + earth connector can run up to 125A of power. We don’t actually have any of these in the building, but like Powerlock, it’s good to know about.
63A TPNE CEEform
The next level down is the 63A version of the above cable. We do have a supply (currently disconnected) in the back corner of the store, but it’s not been used in at least the past 4 years.
32A TPNE CEEform
Stepping down again is the 32A version, and there is a supply here too (in the bar cellar), but it’s also currently disconnected. It was last used by us at the 2010 Freshers Week.
We don’t really use 32A CEEforms, but some of our mobile dimmer packs do require power from a 32A CEEform, but we never supply them with a 32A supply. We have a couple of 13A->32A jump leads around to supply these.
Our main power supplies mainly come through 16A ceeforms, so you’ll see a lot of these around.
For us, blue is used for hard/switched power, whereas yellow is used for dimmed power.
We don’t use any of these (we use 16A ceeforms), but it is the industry standard for < 16A power, usually dimmed power. Quite often any hired equipment will have a 15A plug on it.
Hopefully not much needs to be said about this, other than if you’ve not seen the standard 13A plug before, where have you been!
Otherwise known as a kettle lead, this is a simple 3-pin connector found on low-power rack units and some intelligent lights. It can handle up to 10A.
Also known as figure-of-8, these cables are only used by us to power DJ equipment.