It is interesting to see the different implimentations.
I am assuming that the outlets you have are the 5 pin versions with the central neutral?
Every country has different code practices. In most places when ever you take a higher rated service like 32 amps and then you want to provide outlets that are rated at a lower rate say 10 amps you are required to put a breaker in the line, so as to protect the usually lower gauge wire and connectors that are down stream. I see clipsel makes a box that can plug into a 32 three phase and split out to lower rated boxes, but of course it does not pass on a 32 three phase connection.
US power is quite complicated with different systems
Our residential outlets are 120 volt, with hot, neutral and ground, typically the outlet is rated for 15 amps via the standard 3 prong plug, and multiple outlets can be all wired to the same breaker which is typically 25 amps. In a lot of other countries there is a requirement for a breaker or switch per outlet, this is not the case in the US. Our plugs are not fused either.
We have in homes 220-240 volt appliances such as stove/ air conditioner etc these are wired with two hots, neutral and the ground. Here is where things get complicated. in the typical home, the main service to the house is two 120 volt hot leads, and a common, and ground. The two 120 volt leads are in Phase with one another, and as such if you measure the voltage between the two hot leads, you get the 240 volts. This makes it easy to get multiple 120 volt outlets by simply taking one hot, the neutral and the ground, and our electircal home panels support this with alternating connection to one leg and the other side to the other leg, so when you plug in a dual breaker you get access to the two legs.
Where it gets complicated is the next step up to three phase
There are basically two types of three phase in the US one is called wye and the other delta
In the wye system you have three hots, and a center tap which is the neutral, each phase is 120 degrees from the other, SO if you connect one phase and a neutral, you get 120 volts, but if you connect the two phases and the neutral you get 208 volts due to the phases not being 180 degrees from one another. So wye works fine for deriving 120 volt type service, but you need to be careful that motors etc that need 240 and are not three phase can run on 208 or for instance it is possible to connect a dimmer pack as single phase, BUT it is really dual phase if it is connected to two legs of the wye and it only gets 208 volts, SO for dimmers we can have problems when you go into a small venue and have a portable dimmer pack which is a step up from the back pack type. IF the service is the home 240 service with two 120 and a neutral, ground 4 wire system you can hook it up fine no problems, but if you are on a three phase system, and for instance you don't have the dimmer set up for three phase (5 wires) you could wind up with only 208 volts
In larger venues it is not a problem and if you only work larger venues it is not a problem since you then just have the right cable and connect it in standard 3 phase.
There is another 3 phase system in the US called delta, here there IS no center tap, instead you have power just between the 3 legs, each leg has the full 120 and you do get a full 240 system, BUT it can get dangerous to connect a single phase load to this type of power since you don't have a neutral, and the whole thing gets complicated and you can wind up with what is called a wild leg that has about 190 volts instead of the 120 volts.
Usually when you go above 30 amps in the States in a non professional venue you don't have any plug access, and you need to wire into the main supply.Typically you will have an electrician at the venue if it is small who will
wire you into an appropriate breaker in the main panel, and you will run your own distro system from there. For instance we have a few distro's one for smaller gigs is a 100 amp three phase system, the electrician wires it into the 100 amp breaker in the panel, then we have 150 feet of 5 conductor cable that goes to a roll around rack, inthe rack is a 100 amp three phase panel, and then a series of 20 amp breakers all feeding outlet boxes or socapex 6 circuit connectors. If we wanted we could have done 30 or 60 amp bates connectors for more lights etc.
For carrying high amp loads to a distro we use camlok connectors, there are single wire push on and lock connectors that are made for large gauge wires.
In venues where they do regular performances and people bring in their own equipment, they typically have a disconnect box there. The disconnect is wired permanently into the house system and since it can be switched off it is ok for someone who knows what they are doing and is not an electrician to connect into it . Typically there are 100 amp in small places but are more typically 400 amps.
when you get to professional distro's what you do is have the cables run from the disconnect to the first distro with camlocks (5 three hots red black blue, neutral white and ground green) and plugs into the distro, then there are camlock OUTS on the distro to allow you to then feed the next distro with camlocks also, so you can hook up a string of distro's
Re the comments on ground fault and unbalanced loads
It is not a ground fault that occurs with the unbalancing, it is that since you have three phases of power, 120 degrees out of phase and a common neutral in a balanced system all the current returned is balanced out and you basically have 0 on your neutral BUT if it gets out of balance you can wind up with some voltage on the neutral not the ground.It depends onthe type of load you have on the system. This in sensitive concert pa type stuff can cause some noise problems that can drive you crazy.
http://www.allaboutcircuits.com/vol_2/chpt_10/2.html
http://en.wikipedia.org/wiki/Three-phase_electric_power
Sharyn
I am assuming that the outlets you have are the 5 pin versions with the central neutral?
Every country has different code practices. In most places when ever you take a higher rated service like 32 amps and then you want to provide outlets that are rated at a lower rate say 10 amps you are required to put a breaker in the line, so as to protect the usually lower gauge wire and connectors that are down stream. I see clipsel makes a box that can plug into a 32 three phase and split out to lower rated boxes, but of course it does not pass on a 32 three phase connection.
US power is quite complicated with different systems
Our residential outlets are 120 volt, with hot, neutral and ground, typically the outlet is rated for 15 amps via the standard 3 prong plug, and multiple outlets can be all wired to the same breaker which is typically 25 amps. In a lot of other countries there is a requirement for a breaker or switch per outlet, this is not the case in the US. Our plugs are not fused either.
We have in homes 220-240 volt appliances such as stove/ air conditioner etc these are wired with two hots, neutral and the ground. Here is where things get complicated. in the typical home, the main service to the house is two 120 volt hot leads, and a common, and ground. The two 120 volt leads are in Phase with one another, and as such if you measure the voltage between the two hot leads, you get the 240 volts. This makes it easy to get multiple 120 volt outlets by simply taking one hot, the neutral and the ground, and our electircal home panels support this with alternating connection to one leg and the other side to the other leg, so when you plug in a dual breaker you get access to the two legs.
Where it gets complicated is the next step up to three phase
There are basically two types of three phase in the US one is called wye and the other delta
In the wye system you have three hots, and a center tap which is the neutral, each phase is 120 degrees from the other, SO if you connect one phase and a neutral, you get 120 volts, but if you connect the two phases and the neutral you get 208 volts due to the phases not being 180 degrees from one another. So wye works fine for deriving 120 volt type service, but you need to be careful that motors etc that need 240 and are not three phase can run on 208 or for instance it is possible to connect a dimmer pack as single phase, BUT it is really dual phase if it is connected to two legs of the wye and it only gets 208 volts, SO for dimmers we can have problems when you go into a small venue and have a portable dimmer pack which is a step up from the back pack type. IF the service is the home 240 service with two 120 and a neutral, ground 4 wire system you can hook it up fine no problems, but if you are on a three phase system, and for instance you don't have the dimmer set up for three phase (5 wires) you could wind up with only 208 volts
In larger venues it is not a problem and if you only work larger venues it is not a problem since you then just have the right cable and connect it in standard 3 phase.
There is another 3 phase system in the US called delta, here there IS no center tap, instead you have power just between the 3 legs, each leg has the full 120 and you do get a full 240 system, BUT it can get dangerous to connect a single phase load to this type of power since you don't have a neutral, and the whole thing gets complicated and you can wind up with what is called a wild leg that has about 190 volts instead of the 120 volts.
Usually when you go above 30 amps in the States in a non professional venue you don't have any plug access, and you need to wire into the main supply.Typically you will have an electrician at the venue if it is small who will
wire you into an appropriate breaker in the main panel, and you will run your own distro system from there. For instance we have a few distro's one for smaller gigs is a 100 amp three phase system, the electrician wires it into the 100 amp breaker in the panel, then we have 150 feet of 5 conductor cable that goes to a roll around rack, inthe rack is a 100 amp three phase panel, and then a series of 20 amp breakers all feeding outlet boxes or socapex 6 circuit connectors. If we wanted we could have done 30 or 60 amp bates connectors for more lights etc.
For carrying high amp loads to a distro we use camlok connectors, there are single wire push on and lock connectors that are made for large gauge wires.
In venues where they do regular performances and people bring in their own equipment, they typically have a disconnect box there. The disconnect is wired permanently into the house system and since it can be switched off it is ok for someone who knows what they are doing and is not an electrician to connect into it . Typically there are 100 amp in small places but are more typically 400 amps.
when you get to professional distro's what you do is have the cables run from the disconnect to the first distro with camlocks (5 three hots red black blue, neutral white and ground green) and plugs into the distro, then there are camlock OUTS on the distro to allow you to then feed the next distro with camlocks also, so you can hook up a string of distro's
Re the comments on ground fault and unbalanced loads
It is not a ground fault that occurs with the unbalancing, it is that since you have three phases of power, 120 degrees out of phase and a common neutral in a balanced system all the current returned is balanced out and you basically have 0 on your neutral BUT if it gets out of balance you can wind up with some voltage on the neutral not the ground.It depends onthe type of load you have on the system. This in sensitive concert pa type stuff can cause some noise problems that can drive you crazy.
http://www.allaboutcircuits.com/vol_2/chpt_10/2.html
http://en.wikipedia.org/wiki/Three-phase_electric_power
Sharyn
