Hello.
I have some questions regarding RCD & MCB selection & placement for my garage / workshop.
The Main Consumer Unit
The house is supplied with a 100Amp consumer unit, about 20 years old and containing the old fuse types (the ones where you screw in a length of the correct amperage fuse wire),and no RCD or MCB's in it. There are also NO free slots in the CU.
The Spur
The power to the workshop is supplied with a 1.5cm T&E spur from a 30a ring main socket. The cable run is around 4 meters from the spur to the workshop. The 'spurred' socket is next to the CU.
The workshop
The Spur ends with two double sockets. From these sockets I am running (not all at once though!) :
1200 ish watts tools (saw, drill, sander etc)
4 x 40watt fluroscent light fixtures = total 160watts.
1 x 50watt pond pump ( a long cable on the pump out the window into pond).
Each device is plugged straight into the sockets (ie no extension cables / double-plugs)
So the total load is around 1500w (1.5kw) at any one time.
Questions:
Is this layout safe? It has been fine so far (about 2 yrs), and the spur looks like its been there years...
I would like to add a mini CU before the sockets in the workshop for safety while working. I was thinking of adding an RCD and a MCB in the mini CU.
Although the total circuit works at 6.25 amps (240v, 1.5kw), I understand the tools, pond pump and lights are an 'inductive' load rather than resistive and so the startup amp load is about twice the rated load.
This would mean a total possible load (if everything was turned on at once) of about 12.5 amps? Is this correct?
So I would have to select a type 'C', 16amp MCB. Type 'C' being used for inductive loads.
The closest RCD to my needs is a 63 Amp, 30mA, 2 Pole. I know not to wire the lights into the RCD in case it trips while working...
Does putting the mini cu inline with the spur sound ok?
Is there any adice as to my mcb / rcd selection?
I don't really want to pay a sparkie to do this, as I assume I'll need a new house CU for space for a line to the workshop, which will also need a CU etc etc etc.
I haven't the money to re-do it all. It works fine already and I just want the extra bit of safety an RCD / MCB will provide.
All help is appreciated.
nb The price of a mini CU, RCD & MCB (listed above) is 25 quid total. The price of a 'plug in' RCD is 15 quid. Thats why I'm considering the mini CU option.
I have some questions regarding RCD & MCB selection & placement for my garage / workshop.
The Main Consumer Unit
The house is supplied with a 100Amp consumer unit, about 20 years old and containing the old fuse types (the ones where you screw in a length of the correct amperage fuse wire),and no RCD or MCB's in it. There are also NO free slots in the CU.
The Spur
The power to the workshop is supplied with a 1.5cm T&E spur from a 30a ring main socket. The cable run is around 4 meters from the spur to the workshop. The 'spurred' socket is next to the CU.
The workshop
The Spur ends with two double sockets. From these sockets I am running (not all at once though!) :
1200 ish watts tools (saw, drill, sander etc)
4 x 40watt fluroscent light fixtures = total 160watts.
1 x 50watt pond pump ( a long cable on the pump out the window into pond).
Each device is plugged straight into the sockets (ie no extension cables / double-plugs)
So the total load is around 1500w (1.5kw) at any one time.
Questions:
Is this layout safe? It has been fine so far (about 2 yrs), and the spur looks like its been there years...
I would like to add a mini CU before the sockets in the workshop for safety while working. I was thinking of adding an RCD and a MCB in the mini CU.
Although the total circuit works at 6.25 amps (240v, 1.5kw), I understand the tools, pond pump and lights are an 'inductive' load rather than resistive and so the startup amp load is about twice the rated load.
This would mean a total possible load (if everything was turned on at once) of about 12.5 amps? Is this correct?
So I would have to select a type 'C', 16amp MCB. Type 'C' being used for inductive loads.
The closest RCD to my needs is a 63 Amp, 30mA, 2 Pole. I know not to wire the lights into the RCD in case it trips while working...
Does putting the mini cu inline with the spur sound ok?
Is there any adice as to my mcb / rcd selection?
I don't really want to pay a sparkie to do this, as I assume I'll need a new house CU for space for a line to the workshop, which will also need a CU etc etc etc.
I haven't the money to re-do it all. It works fine already and I just want the extra bit of safety an RCD / MCB will provide.
All help is appreciated.
nb The price of a mini CU, RCD & MCB (listed above) is 25 quid total. The price of a 'plug in' RCD is 15 quid. Thats why I'm considering the mini CU option.