Consumer Units And How They Work
The consumer unit is the name given to the unit that distributes electricity throughout the home, factory or building of any kind.
The regulations have changed so much over the years and there still seems to be an ever increasing set of regulations.
The upshot has been to make the distribution of electricity so much safer and much more flexible than previously.
The latest group of regulations are the 17th edition and the industry is bound by law to manufacture their consumer units to meet the criteria laid out in these regulations.
One of the major criteria is that the unit must be protected against earth leakage with an RCD or Residual Current Device, with the exception of certain specialist circuits and devices.
The Residual Current Device switches the whole circuit off instantly should such an earth leakage occur.
This can be particularly annoying if the system is very sensitive and there is an element of nuisance tripping of the circuit breaker this is often caused in circuits with split loads.
Some manufacturers have produced some good consumer units that do have the ability to reduce or remove this problem.
Also some of the more modern units have the system to set up the lighting circuits so that they are split into two separate circuits, so that if a bulbs blows or there is a fault on one circuit you are left with 50% of the lights in operation.
The provision of specialist circuits is quite an art in itself in that you do not want circuits like the fire alarm or burglar alarm to switch off instantly for something minor for very obvious reasons in that if there was a fire and it caused a RCD to trip then the alarm should not go off.
The same thing is useful for a burglar alarm although most burglar and fire alarms in many cases do have battery back ups or even emergency generators in factories, the functions they control may be limited.
Certain other circuits such as freezers and fish tanks can need protection from a special circuit.
One of the major problems with certain consumer units is that if the specialist circuit goes off on its own because it is not like a lighting system when a broken circuit is immediately recognised by darkness in this case there is no visual warning of a loss of power.
In this case a specialist circuit such as a freezer or other may be tripped out and with no warning that the circuit is broken there can be expensive consequences.
The regulations have changed so much over the years and there still seems to be an ever increasing set of regulations.
The upshot has been to make the distribution of electricity so much safer and much more flexible than previously.
The latest group of regulations are the 17th edition and the industry is bound by law to manufacture their consumer units to meet the criteria laid out in these regulations.
One of the major criteria is that the unit must be protected against earth leakage with an RCD or Residual Current Device, with the exception of certain specialist circuits and devices.
The Residual Current Device switches the whole circuit off instantly should such an earth leakage occur.
This can be particularly annoying if the system is very sensitive and there is an element of nuisance tripping of the circuit breaker this is often caused in circuits with split loads.
Some manufacturers have produced some good consumer units that do have the ability to reduce or remove this problem.
Also some of the more modern units have the system to set up the lighting circuits so that they are split into two separate circuits, so that if a bulbs blows or there is a fault on one circuit you are left with 50% of the lights in operation.
The provision of specialist circuits is quite an art in itself in that you do not want circuits like the fire alarm or burglar alarm to switch off instantly for something minor for very obvious reasons in that if there was a fire and it caused a RCD to trip then the alarm should not go off.
The same thing is useful for a burglar alarm although most burglar and fire alarms in many cases do have battery back ups or even emergency generators in factories, the functions they control may be limited.
Certain other circuits such as freezers and fish tanks can need protection from a special circuit.
One of the major problems with certain consumer units is that if the specialist circuit goes off on its own because it is not like a lighting system when a broken circuit is immediately recognised by darkness in this case there is no visual warning of a loss of power.
In this case a specialist circuit such as a freezer or other may be tripped out and with no warning that the circuit is broken there can be expensive consequences.
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