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Do I RCD protect the oven and hob or not?
Currently I have a split load consumer unit, boths sides have their own 30mA
RCD It is split into lighing one side, and everthing else the other. I am adding a second CU for non-RCD protected things (Alarm, freezers and feeds to smaller comsomer units in the shed & garage) Would it be advisable to put the oven and induction hob feeds on this non RCD CU? Sparks... |
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#2
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Sparks wrote: Currently I have a split load consumer unit, boths sides have their own 30mA RCD It is split into lighing one side, and everthing else the other. I am adding a second CU for non-RCD protected things (Alarm, freezers and feeds to smaller comsomer units in the shed & garage) Would it be advisable to put the oven and induction hob feeds on this non RCD CU? Sparks... |
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#3
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Hi Sparticus,
You should put the hob and oven on an rcd protective device if one is available, obviously if they are not on rcd it will still comply with the iee 16th ed regs (excluding outside/garden barbecues/sockets, etc), though if you have a circuit available with rcd protection for the hob/oven then use it. You shouldn't really put lighting circuits on rcd protective circuits, hence the idea of a split consumer unit, as a trip of the lighting causes a hazard in itself, also alarm circuits i.e. fire/intruder (without outlets should be dedicated circuits) should also not be rcd proctected for similar reasons. Regs Alan Sparks wrote: Currently I have a split load consumer unit, boths sides have their own 30mA RCD It is split into lighing one side, and everthing else the other. I am adding a second CU for non-RCD protected things (Alarm, freezers and feeds to smaller comsomer units in the shed & garage) Would it be advisable to put the oven and induction hob feeds on this non RCD CU? Sparks... |
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#4
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"waddy" wrote in message oups.com... Hi Sparticus, You shouldn't really put lighting circuits on rcd protective circuits, hence the idea of a split consumer unit, as a trip of the lighting causes a hazard in itself, also alarm circuits i.e. fire/intruder (without outlets should be dedicated circuits) should also not be rcd proctected for similar reasons. Regs Alan I have always been amazed in this day and of implied safety, you're still allowed to have bare connectors associated with light fittings without any protection at 230V AC. What do you think will be in the 17th Edition? |
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#5
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They don't need RCD protecting, and oven elements can cause
tripping whilst not presenting any significant electrocution risk which means it's not a brilliant idea to have them sharing an RCD with anything else. So normally, they go on the non-RCD protected side. Another thing I should have said, or asked, What type of earthing system do you have? If it's a TT system, you can't normally have any non-RCD protected circuits (except possibly for some low current ones if you can prove the earth fault loop impedance is OK for them). This might be the reason you have all circuits RCD protected (although some of them should be at = 100mA). The house is a TN-S (Supplied by the electricity company's cable) Incedently, this earth wire from the head to the CU seems to be about 4mm or 6mm - is this normal, or should it be replaced with heavier cable? If so, do I ask the electricity company, as it is sealed in the lower part of the cable head? Sparks... |
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#6
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Sparks wrote:
Currently I have a split load consumer unit, boths sides have their own 30mA RCD It is split into lighing one side, and everthing else the other. I am adding a second CU for non-RCD protected things (Alarm, freezers and feeds to smaller comsomer units in the shed & garage) Would it be advisable to put the oven and induction hob feeds on this non RCD CU? Sparks... "waddy" wrote in message oups.com... Hi Sparticus, You should put the hob and oven on an rcd protective device if one is available, obviously if they are not on rcd it will still comply with the iee 16th ed regs (excluding outside/garden barbecues/sockets, etc), though if you have a circuit available with rcd protection for the hob/oven then use it. You shouldn't really put lighting circuits on rcd protective circuits, hence the idea of a split consumer unit, as a trip of the lighting causes a hazard in itself, also alarm circuits i.e. fire/intruder (without outlets should be dedicated circuits) should also not be rcd proctected for similar reasons. So, for the fridge and freezer, should these be hard wired, so not having a socket on an unprotected circuit? Sparks... |
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#7
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Sparks wrote:
Would it be advisable to put the oven and induction hob feeds on this non RCD CU? My preference would be to put those fixed loads on the non RCD side. The Regs certainly don't require them to be RCDed; and the older your oven and grill elements get (also radiant and 'sealed' hotplates, but not induction plates as you have) the more they pass a small leakage current, especially when cold and a little damp (e.g. after a steamy baking session as the elements cool down). Putting these on a shared RCD predisposes that RCD to nuisance tripping. But if you prefer the added reassurance that slopping salty spud-boiling water about will cut the supply should it drip where it shouldn't, there's nothing deeply bad about putting it on the RCD side. You could always (assuming enough slack at the CU end) start off with it on the RCD side, and move it across to the non-RCD CU if you get nuisance trips which sort-of tie in with turning the cooker on. In my direct experience of this, with a whole-house RCD (as used to be the fashion), young kids (so making me keen on keeping the whole-house RCD until they were past the fingerpoken age - 85, isn't it? ;-), a coupla 'emergency' lights which came on if the power failed, and a growing number of switched-mode-PSU computers and mains-filtered appliances, *oh* and an RCD which on test showed it'd trip at under 14mA! - it was still only rare that turning on the cooker ring/grill would make the RCD trip immediately; rather, it'd pop a minute or two after you'd started to use the cooker. Maybe an element had to expand a little first to bring a live conductor close enough to the earthed casing to leak enough... maybe it was just pixies at work ;-) HTH - Stefek |
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#8
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Fred wrote:
I have always been amazed in this day and of implied safety, you're still allowed to have bare connectors associated with light fittings without any protection at 230V AC. It comes down to which is the greater danger, being plunged into darkness or being electrocuted... FWIW our lighting circuits are RCD protected and are staying like it  Lee -- Email address is valid, but is unlikely to be read. |
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#9
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"Sparks" wrote in message .. . Currently I have a split load consumer unit, boths sides have their own 30mA RCD It is split into lighing one side, and everthing else the other. I am adding a second CU for non-RCD protected things (Alarm, freezers and feeds to smaller comsomer units in the shed & garage) Would it be advisable to put the oven and induction hob feeds on this non RCD CU? Sparks... Why have you got 2 RCD's are you sure they are both RCD's? If so I'd remove the one supplying the lighting and add the other circuits to it, if you have room and don't overload the cu! If the oven switch has a 13 amp outlet on it then it must be rcd protected, otherwise up to u. |
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#10
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Dave Jones wrote:
If the oven switch has a 13 amp outlet on it then it must be rcd protected, otherwise up to u. I can think of few downstairs sockets *less* likely to get an outdoor appliance plugged in than the one permanently occupied by the householder's kettle - so I don't understand why you hold with such certainty that a cooker-control unit with integral socket 'must' be RCD protected... |
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#11
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"Stefek Zaba" wrote in message
... Sparks wrote: The house is a TN-S (Supplied by the electricity company's cable) Incedently, this earth wire from the head to the CU seems to be about 4mm or 6mm - is this normal, or should it be replaced with heavier cable? If so, do I ask the electricity company, as it is sealed in the lower part of the cable head? It will have been compliant when installed - maybe, say 14th Edn of t'Regs. Theze Dayz it'd be 16mmsq or so. Not sure there's a *vast* benefit in getting the supply co out to upgrade - they may then want you (or at least suggest you should) up the rest of your own bonding to 10mmsq/16mmsq, and/or PMEify you... So, if it was compliant at some point, it would still pass an inspection now? If that is that case. surely that is a bit stupid, as if the regulations have changed, the older ones must now be deemed unsafe? Sparks... |
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#12
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In article ,
"Sparks" writes: Currently I have a split load consumer unit, boths sides have their own 30mA RCD It is split into lighing one side, and everthing else the other. I am adding a second CU for non-RCD protected things (Alarm, freezers and feeds to smaller comsomer units in the shed & garage) Would it be advisable to put the oven and induction hob feeds on this non RCD CU? They don't need RCD protecting, and oven elements can cause tripping whilst not presenting any significant electrocution risk which means it's not a brilliant idea to have them sharing an RCD with anything else. So normally, they go on the non-RCD protected side. -- Andrew Gabriel |
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#13
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#14
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On Wed, 30 Mar 2005 20:30:02 GMT, Lee
wrote: It comes down to which is the greater danger, being plunged into darkness or being electrocuted... That one is a complete no brainer. The number of people killed or severely injured by electrocution in domestic accidents the UK each year is very small. Even if you include accidents which are not electrocution but attributable to it (such as falling off a ladder after touching a live cable) the numbers involved in domestic accidents are still small, about 25 deaths and 2000 injuries of all severities (compare this with 70 deaths and 40,000 injuries caused by DIY!). Those figures have not reduced since whole house RCD's started to be used but are expected to rise with Part P dissuading people from installing extra sockets and increasing the use of extension leads. The total number of people killed in accidents in the home each year is about 4,000, of this roughly half are due to falls and about 1,000 due to falls down stairs. The number of people killed or injured in house fires is also depressingly large, many times greater than those killed by electrocution. Typically 500 people die and 18,000 are seriously injured each year by fire in the home. Of these deaths about 20 are attributable to electrical fires some of which an RCD might have prevented. The remainder are caused by non-electrical ignition. Of the 4,000 people killed in both falls and fires each year there is no easily available breakdown of contributory factors. However some police and fire reports do give further information. Of these I have seen only a very small number from one area, however within these there were a significant minority, probably about 10-20 which mentioned that lights were out and could not be turned back on from the light switch when the emergency services arrived. Only one or two of these, usually fire service reports, specifically mention RCD's having tripped. Nonetheless it is reasonable to infer even from this imperfect data that the number of people killed in falls and fires in which tripped RCD's were the cause or a major contributory factor is significantly higher than the number of people protected by them _in the home_. In the garden or garage is quite another matter. FWIW our lighting circuits are RCD protected and are staying like it I suggest you invest in a book on basic risk assessment. -- Peter Parry. http://www.wpp.ltd.uk/ |
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#15
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On 30 Mar 2005 10:32:58 -0800, "waddy"
wrote: You should put the hob and oven on an rcd protective device if one is available, What benefit will this bring? -- Peter Parry. http://www.wpp.ltd.uk/ |
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#16
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Sparks wrote:
The house is a TN-S (Supplied by the electricity company's cable) Incedently, this earth wire from the head to the CU seems to be about 4mm or 6mm - is this normal, or should it be replaced with heavier cable? If so, do I ask the electricity company, as it is sealed in the lower part of the cable head? It will have been compliant when installed - maybe, say 14th Edn of t'Regs. Theze Dayz it'd be 16mmsq or so. Not sure there's a *vast* benefit in getting the supply co out to upgrade - they may then want you (or at least suggest you should) up the rest of your own bonding to 10mmsq/16mmsq, and/or PMEify you... |
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#17
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Peter Parry wrote:
I suggest you invest in a book on basic risk assessment. Just because we chose one slight benefit over a possible risk does not mean that we are unaware that risk. We are unlikely to fall down stairs we don't have, for instance... Lee -- Email address is valid, but is unlikely to be read. |
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#18
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In article ,
Sparks wrote: Would it be advisable to put the oven and induction hob feeds on this non RCD CU? Yes. There's no point in RCD protecting permanently connected devices like this - and since they may well have mineral insulated heating elements might cause nuisance tripping. -- *Change is inevitable, except from a vending machine. Dave Plowman London SW To e-mail, change noise into sound. |
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#19
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In article ,
Fred wrote: I have always been amazed in this day and of implied safety, you're still allowed to have bare connectors associated with light fittings without any protection at 230V AC. I tend to agree. I know the arguments about a blown bulb plunging the house into darkness - but think the hazards of Joe Bloggs replacing a bulb on a possibly live circuit more of a risk. IMHO. -- *Dance like nobody's watching. Dave Plowman London SW To e-mail, change noise into sound. |
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#20
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In message , Lee
writes Peter Parry wrote: I suggest you invest in a book on basic risk assessment. Just because we chose one slight benefit over a possible risk does not mean that we are unaware that risk. We are unlikely to fall down stairs we don't have, for instance... But for those of us with real stairs ... No I'm not going there, what are the upright bits of a bannister called, and where can you buy them Off to book my holiday to Indonesia, prolly safer -- geoff |
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#21
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Sparks wrote:
If that is that case. surely that is a bit stupid, as if the regulations have changed, the older ones must now be deemed unsafe? No - there's every difference between 'unsafe' and 'not to latest standards for a new installation'. There's no obligation to keep an installation continually updated in line with Regs changes (though I bet the NICEIC would *lurv* such a principle to be established). There's a specific category for 'not in line with latest Regs but not presenting any problem' on the standard Periodic Inspection form (scrabbles for OSG: ah yes, here it is.) There's a 4-level "recommendation" scale, thus: "1 - requires urgent attention; 2 - requires improvement; 3 - requires further investigation; 4 - does not comply with BS 7671:2001 amended to date. This does not imply that the electrical installation inspected is unsafe." HTH - Stefek |
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#22
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Sparks wrote:
Currently I have a split load consumer unit, boths sides have their own 30mA RCD It is split into lighing one side, and everthing else the other. I am adding a second CU for non-RCD protected things (Alarm, freezers and feeds to smaller comsomer units in the shed & garage) Would it be advisable to put the oven and induction hob feeds on this non RCD CU? Sparks... No idea what regs apply, but I personally like a BIG RCD - 100mA - for the whole house, and 30mA RCBO's for where the regs say its needed. Cookers aint it though. I do not believe there is a requirement to RCD them I believe the philosophy is where portable appliances have cables whose earth may become cut or disconnected and/or the appliance may become damp. |
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#23
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In article ,
"Fred" writes: I have always been amazed in this day and of implied safety, you're still allowed to have bare connectors associated with light fittings without any protection at 230V AC. When doing portable appliance testing and checking for IP2X (fingers can't access live parts), lampholders is the one exception allowed there. (The usual causes for failures on this test are old electric fires with the grill guard spacing large enough to poke a finger through.) -- Andrew Gabriel |
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#24
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raden wrote:
what are the upright bits of a bannister called, and where can you buy them Newel post, or Spindles (depending on if you mean the thick ones at the ends or dainty bits in the middle. Screwfix have a small selection. -- Cheers, John. /================================================== ===============\ | Internode Ltd - http://www.internode.co.uk | |-----------------------------------------------------------------| | John Rumm - john(at)internode(dot)co(dot)uk | \================================================= ================/ |
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#25
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In article ,
John Rumm writes: raden wrote: what are the upright bits of a bannister called, and where can you buy them Newel post, or Spindles (depending on if you mean the thick ones at the ends or dainty bits in the middle. or balustrades for a generic term that covers spindles and non- turned/spun equivalents. Screwfix have a small selection. Richard Burbridge is a manufacturer stocked by B&Q and many of the builders merchants. Wickes have their own equivalent range. When I built my bannisters, I used a Richard Burbridge handrail, but I made all the other parts from scratch from planed timber. -- Andrew Gabriel |
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#26
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"Andrew Gabriel" wrote in message ... In article , "Fred" writes: I have always been amazed in this day and of implied safety, you're still allowed to have bare connectors associated with light fittings without any protection at 230V AC. When doing portable appliance testing and checking for IP2X (fingers can't access live parts), lampholders is the one exception allowed there. (The usual causes for failures on this test are old electric fires with the grill guard spacing large enough to poke a finger through.) -- Andrew Gabriel Can these fires be re-labelled as an incandescent light? |
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#27
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Dave Plowman (News) wrote:
Yes. There's no point in RCD protecting permanently connected devices like this - and since they may well have mineral insulated heating elements might cause nuisance tripping. One, admittedly tenuous, advantage to putting a cooker on an RCD, is that it's more likely a "soft" failure when there is a fault - might be better for those of a nervous disposition than a "bang" from a failed element  Lee -- Email address is valid, but is unlikely to be read. |
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#28
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In article ,
Lee writes: One, admittedly tenuous, advantage to putting a cooker on an RCD, is that it's more likely a "soft" failure when there is a fault - might be better for those of a nervous disposition than a "bang" from a failed element So you end up with an unusable oven which trips everything else. If it wasn't on an RCD, it would continue working fine for years, as the element will drive off the moisture causing the leak within a few seconds of switching on. You don't generally get bangs from failed elements -- they eventually just go open circuit, possibly with a little arcing, but basically pretty harmlessly. -- Andrew Gabriel |
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#29
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In message , John
Rumm writes raden wrote: what are the upright bits of a bannister called, and where can you buy them Newel post, or Spindles (depending on if you mean the thick ones at the ends or dainty bits in the middle. I know, I wasn't really expecting a reply on that one -- geoff |
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#30
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Andrew Gabriel wrote:
You don't generally get bangs from failed elements -- they eventually just go open circuit, possibly with a little arcing, but basically pretty harmlessly. It was meant tongue in cheek - did you spot the smilies? Though I have seen some pretty noisy element failures in the past - especially the old "ring" type hobs. I take it modern designs don't fail like that any more then? Lee -- Email address is valid, but is unlikely to be read. |
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#31
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"Stefek Zaba" wrote in message ... Dave Jones wrote: If the oven switch has a 13 amp outlet on it then it must be rcd protected, otherwise up to u. I can think of few downstairs sockets *less* likely to get an outdoor appliance plugged in than the one permanently occupied by the householder's kettle - so I don't understand why you hold with such certainty that a cooker-control unit with integral socket 'must' be RCD protected... Due to the current regulations, "all downstairs socket outlets must be rcd protected". Wouldn't that depends on the position of your cooker with location to the nearest window, majority of council properties I've been to have the cooker near a window or the back door, ideal for plugging in the lawnmower! |
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#32
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Dave Jones wrote:
Due to the current regulations, "all downstairs socket outlets must be rcd protected". No, that's not the wording. The wording's closer to 'sockets it can reasonably be foreseen that an outdoor appliance will be plugged in to'. It's then a common interpretation to take that to mean 'all downstairs sockets' - AFAIR that's what Whitfield suggests - but it's down to common sense. If there are other kitchen sockets closer to door/window, much more so if there's a handy outdoor socket on the outside wall - *that*'s where yer lawnmower, hedge trimmer, yada yada is going to get plugged in. You could even label the cooker-unit socket with a pretty "INDOOR USE ONLY!" notice, to drive the point home. Still, there's common-sense and let-Darwin-rule; and then there's jobbing electricians who need to cover their posteriors lest Wayne and Waynetta stick the where-there's-blame mob onto them, I guess... |
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#33
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Stefek Zaba wrote:
If the oven switch has a 13 amp outlet on it then it must be rcd protected, otherwise up to u. I can think of few downstairs sockets *less* likely to get an outdoor appliance plugged in than the one permanently occupied by the householder's kettle I don't know why kettles are plugged into cooker control units. In the days when the cooker unit was the only outlet in the kitchen rated higher than a BC lampholder adapter perhaps. My kettle's plugged in next to the sink as that's where it gets filled for tea and emptied for the odd top-up of boiling water for the washing-up. The cooker socket at the other end of the kitchen (and nearest the window, so most likely to be used for outdoor appliance apart from the fact that this is an upstairs flat) is used for the fridge. Owain |
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#34
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"Stefek Zaba" wrote in message ... Dave Jones wrote: Due to the current regulations, "all downstairs socket outlets must be rcd protected". No, that's not the wording. The wording's closer to 'sockets it can reasonably be foreseen that an outdoor appliance will be plugged in to'. It's then a common interpretation to take that to mean 'all downstairs sockets' - AFAIR that's what Whitfield suggests - but it's down to common sense. If there are other kitchen sockets closer to door/window, much more so if there's a handy outdoor socket on the outside wall - *that*'s where yer lawnmower, hedge trimmer, yada yada is going to get plugged in. You could even label the cooker-unit socket with a pretty "INDOOR USE ONLY!" notice, to drive the point home. Still, there's common-sense and let-Darwin-rule; and then there's jobbing electricians who need to cover their posteriors lest Wayne and Waynetta stick the where-there's-blame mob onto them, I guess... Common sense doesn't really come into it, the majority of people will wall into a kitchen and plug the lead into any available socket, ie if the cooker skt is empty they will use it, no matter if there is one by the back door with the toaster in, they would rather run a lead across the room than take out a plug of unused item. |
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#35
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In article ,
"Dave Jones" writes: "Stefek Zaba" wrote in message ... Dave Jones wrote: If the oven switch has a 13 amp outlet on it then it must be rcd protected, otherwise up to u. I can think of few downstairs sockets *less* likely to get an outdoor appliance plugged in than the one permanently occupied by the householder's kettle - so I don't understand why you hold with such certainty that a cooker-control unit with integral socket 'must' be RCD protected... I never use those combined cooker control panel plus socket. This is because I don't put cookers on RCDs for reasons explained elsewhere recently, but I do RCD protect all the kitchen worktop socket outlets (even when this isn't required by the regs). Due to the current regulations, "all downstairs socket outlets must be rcd protected". This isn't the case. Only sockets which might be used to power outdoor appliances need to be RCD protected. If you have a good provision of sockets outdoors anyway, it's unlikely any of the indoor ones are likely to be used for this purpose. Actually, one place I have used a combined cooker control panel is for the outdoor sockets. The panel is in the garage next to the door with the switched socket handy for running tools just outside the garage, and the large switch is used to isolate all the other sockets which are outdoors in the front and back gardens. I went for one with neon indicators so you can quickly see if the RCD has tripped. The cooker control panel seemed ideal for this task. The whole radial circuit is on a dedicated 20A/10mA RCBO with own TT earthing system. -- Andrew Gabriel |
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#36
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Due to the current regulations, "all downstairs socket outlets must be
rcd protected". This isn't the case. Only sockets which might be used to power outdoor appliances need to be RCD protected. If you have a good provision of sockets outdoors anyway, it's unlikely any of the indoor ones are likely to be used for this purpose. If this is really the case, then surelly ALL sockets must be RCD protected in the whole house, as at some point any of them *might* be used for an outside appliance? (For example, say there is a socket behind the fridge, it is not impossible for this to be used for outdoor appliances - yes, it's highly unlikley, but it just might happen! |
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