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Regbuser said:
This is true.
However, this thread seems to be driven by enthusiastic amateurs, who'd like to do the right thing (mostly).
They might not want to spend £20 extra on a robust metal bodied luminaire that can accept a more robust cabling solution.
They might buy a cheap unit that comes with a metre of 0.5 flex moulded on, then wonder how they can chocolate block it up to a socket and flying lead out of a window ..
And your point is?!? However, this thread seems to be driven by enthusiastic amateurs, who'd like to do the right thing (mostly).
They might not want to spend £20 extra on a robust metal bodied luminaire that can accept a more robust cabling solution.
They might buy a cheap unit that comes with a metre of 0.5 flex moulded on, then wonder how they can chocolate block it up to a socket and flying lead out of a window ..
essayer said:
dhutch said:
H07RN-F
I was looking for black cable to use outside (not SWA) and I could see rubber versions of this, but conflicting ideas as to whether it could be used outside or not (UV protection etc).. anyone have thoughts? Prefer to avoid conduitruggedscotty said:
the 18th edition wiring requirements, 2nd ammendment has said that you can provide an addittional provision at your main earth terminal by way of an earth rod. If this was o then you could connect the earth wire through to the outshouse.
411.4.2 It is recommended that an additional connection to Earth, by means of an earth electrode in accordance with Chapter 54, is made to the main earthing terminal. This recommendation does not apply to outbuildings of dwellings served by the installation.
Comment: In amendment 1 there was a note that referenced that an additional earthing connection could be made to the protective earth or PEN conductor. This has now been expanded upon and introduced as a recommendation. Essentially, with metal pipework and lead covered cables being replaced by plastic equivalents, the risks associated with PME supplies are increasing and customers are having to provide additional reinforcement to the DNO network by installing an additional electrode to the MET.
So by waht you have said - earth electrode in yopur house one at the summer house. If this is so then I would connect the earth between the summer house and the main dwelling.
I wish they'd decide once and for all if pme is "safe" or not and what to do with it. Rather than dally around. I've known sparks 30 years ago who'd rod in addition, mind it seems the they who write the regs tend to be a gulf from the guys who do the job.411.4.2 It is recommended that an additional connection to Earth, by means of an earth electrode in accordance with Chapter 54, is made to the main earthing terminal. This recommendation does not apply to outbuildings of dwellings served by the installation.
Comment: In amendment 1 there was a note that referenced that an additional earthing connection could be made to the protective earth or PEN conductor. This has now been expanded upon and introduced as a recommendation. Essentially, with metal pipework and lead covered cables being replaced by plastic equivalents, the risks associated with PME supplies are increasing and customers are having to provide additional reinforcement to the DNO network by installing an additional electrode to the MET.
So by waht you have said - earth electrode in yopur house one at the summer house. If this is so then I would connect the earth between the summer house and the main dwelling.
I did call the NIC advice line on what to code an exported pme earth to a summer house a few years ago, so long as it wasn't a metal framed structure he wasn't fussed.
I have a question about solar panel voltages. I suspect we may have up to four faulty solar panels but I'm not certain.
When installed last October our 18 panel system tested at 353v on both 9 panel strings. On a sunny day it regularly maxed out our 6kw inverter. Recently I've noticed super sunny days only achieve around 5.8kw and it's never maxed out.
The Solis inverter consistently displays voltage for both strings now at around 280v. I understand these Trina 390w panels have a nominal voltage of 40v per panel (40v x 9 = 360v) which is roughly the original installed test voltage.
Does this suggest both strings are now missing two panels each? (40v x 7 = 280v)
Our installers were a bit of a nightmare to work with so please enlighten me before speak to them.
Ta.
When installed last October our 18 panel system tested at 353v on both 9 panel strings. On a sunny day it regularly maxed out our 6kw inverter. Recently I've noticed super sunny days only achieve around 5.8kw and it's never maxed out.
The Solis inverter consistently displays voltage for both strings now at around 280v. I understand these Trina 390w panels have a nominal voltage of 40v per panel (40v x 9 = 360v) which is roughly the original installed test voltage.
Does this suggest both strings are now missing two panels each? (40v x 7 = 280v)
Our installers were a bit of a nightmare to work with so please enlighten me before speak to them.
Ta.
DMAndy said:
I have a question about solar panel voltages. I suspect we may have up to four faulty solar panels but I'm not certain.
When installed last October our 18 panel system tested at 353v on both 9 panel strings. On a sunny day it regularly maxed out our 6kw inverter. Recently I've noticed super sunny days only achieve around 5.8kw and it's never maxed out.
The Solis inverter consistently displays voltage for both strings now at around 280v. I understand these Trina 390w panels have a nominal voltage of 40v per panel (40v x 9 = 360v) which is roughly the original installed test voltage.
Does this suggest both strings are now missing two panels each? (40v x 7 = 280v)
Our installers were a bit of a nightmare to work with so please enlighten me before speak to them.
Ta.
There can be several reasons why the voltage of a solar panel might drop. Here are a few possible explanations:When installed last October our 18 panel system tested at 353v on both 9 panel strings. On a sunny day it regularly maxed out our 6kw inverter. Recently I've noticed super sunny days only achieve around 5.8kw and it's never maxed out.
The Solis inverter consistently displays voltage for both strings now at around 280v. I understand these Trina 390w panels have a nominal voltage of 40v per panel (40v x 9 = 360v) which is roughly the original installed test voltage.
Does this suggest both strings are now missing two panels each? (40v x 7 = 280v)
Our installers were a bit of a nightmare to work with so please enlighten me before speak to them.
Ta.
Insufficient Sunlight: Solar panels generate electricity when exposed to sunlight. If there is a decrease in sunlight intensity, such as during cloudy weather or when the panel is partially shaded, the voltage output of the panel can drop. Shadows from nearby objects, dust, or dirt on the panel's surface can also reduce the amount of sunlight reaching the cells and result in decreased voltage.
Temperature: Solar panels are designed to operate optimally within a certain temperature range. When the temperature exceeds this range, the efficiency of the solar cells can be affected, leading to a decrease in voltage output. High ambient temperatures, excessive heat buildup on the panel's surface, or inadequate ventilation can all contribute to a drop in voltage.
Aging and Degradation: Over time, solar panels can experience a natural degradation process. The performance of the cells and their ability to convert sunlight into electricity may gradually decline, resulting in a lower voltage output. Factors like prolonged exposure to harsh weather conditions, UV radiation, and wear and tear can contribute to the aging process of solar panels.
Electrical Issues: Faulty wiring, loose connections, or damaged components in the solar panel system can cause voltage drops. Problems in the electrical circuit, such as high resistance or poor conductivity, can lead to voltage losses along the wiring or connections, resulting in reduced voltage at the output.
System Design or Configuration: In some cases, the voltage drop may be due to an issue with the overall design or configuration of the solar panel system. Improper sizing or mismatched components, such as inverters or charge controllers, can lead to voltage inconsistencies and drops.
Can you get to the panels and clean them? Not sure where you are but we haven’t had any rain for probably a month and Velux windows and glass atrium are very dusty.
No system on the current house had had them for 10 years on previous house - during the summer months the panels produced less peak power because they were hotter.
What angle are they mounted at?
No system on the current house had had them for 10 years on previous house - during the summer months the panels produced less peak power because they were hotter.
What angle are they mounted at?
Interesting. We're yet to experience a summer with panels so maybe my expectations are off. Back in March/April when it was sunny but cool we were regularly clipping at the 6kw limit of our inverter. I had assumed that would either continue or increase during hot summer days but now we're under.
I actually managed to wash the first two rows this week which made a very marginal (1-2%) difference. My window cleaning pole couldn't quite reach the third row.
35 degree pitch if I recall correctly.
I certainly appreciate your feedback. Tell me if I'm expecting too much but I though higher longer sunny periods would have yielded even higher power.
I actually managed to wash the first two rows this week which made a very marginal (1-2%) difference. My window cleaning pole couldn't quite reach the third row.
35 degree pitch if I recall correctly.
I certainly appreciate your feedback. Tell me if I'm expecting too much but I though higher longer sunny periods would have yielded even higher power.
See if you can find the data sheet for your particular panel; there should be a table listing the temperature ratings. Here’s an example https://static.trinasolar.com/sites/default/files/... The quoted output is as stated with a panel temp of 25 C.
For every degree it’s above 25 C the panel’s output voltage drops by 0.25%. I remember sticking a thermometer on the back of the panels but don’t recall the max temp. It was well higher than ambient though; too hot to touch. If it was 60 C then the panels would lose almost 10% due to temperature alone. Combine that with some dust and some haze in the sky and it sounds like all is as to be expected. The proof will be in Sept and Oct when the sun is still strong but the temps are cooler.
For every degree it’s above 25 C the panel’s output voltage drops by 0.25%. I remember sticking a thermometer on the back of the panels but don’t recall the max temp. It was well higher than ambient though; too hot to touch. If it was 60 C then the panels would lose almost 10% due to temperature alone. Combine that with some dust and some haze in the sky and it sounds like all is as to be expected. The proof will be in Sept and Oct when the sun is still strong but the temps are cooler.
And if you want to go into full anorak mode and have a way to monitor inverter output in real time…
on a hot and sunny day carefully mist (to slowly cool them) the panels with the hosepipe and then drench them in water for a few minutes until they’re nice and cool and then stop. You’ll see the output drop as the water reflects/refracts the sunlight. Shortly after the watering stops and the water evaporates the output will shoot up as the cool panels are more efficient. Then the output will come down as the panels heat up again.
on a hot and sunny day carefully mist (to slowly cool them) the panels with the hosepipe and then drench them in water for a few minutes until they’re nice and cool and then stop. You’ll see the output drop as the water reflects/refracts the sunlight. Shortly after the watering stops and the water evaporates the output will shoot up as the cool panels are more efficient. Then the output will come down as the panels heat up again.
So I would like some insight on how a sparky would go about this.
We moved in the new year and are now starting to get things done to the house. One area that needs work is the electrics.
I'm going to get a sparky to install a new CU, new Aico smokes, heat, CO etc. Put a separate CU in the garage for the garage.
However currently there are two MCBs for the house sockets. One for the kitchen, utility, the bedroom above the kitchen and the garage. Then one for for the rest of the house (3 other bedrooms, office, living room, dining room, conservatory).
I'd ideally like the kitchen/utility to be on its own, then split the current setup to be upstairs sockets and downstairs sockets. I'd also like extra sockets adding upstairs and down.
I'm currently replacing some floorboards upstairs so had a nose how it was wired. It's wired as upstairs sockets on a ring with each of the downstairs sockets spured from an upstairs socket. It looks like quite small conduit running down and I doubt you'd get another 2.5 T&E down to either create a ring or radial. Guess you could try with singles.
So what would be the best practical way about this? Obviously you could rip out the current conduit, fit bigger and run the wiring etc but obviously that would be a lot of mess (I think the mrs would like chasing kept to a minimum). Would you leave it how it is and put the extra sockets I want on a separate circuit instead? Just wondered if there's a simple answer as I've not come across this set up before.
Just interested in professional thoughts before I get some sparkys round.
We moved in the new year and are now starting to get things done to the house. One area that needs work is the electrics.
I'm going to get a sparky to install a new CU, new Aico smokes, heat, CO etc. Put a separate CU in the garage for the garage.
However currently there are two MCBs for the house sockets. One for the kitchen, utility, the bedroom above the kitchen and the garage. Then one for for the rest of the house (3 other bedrooms, office, living room, dining room, conservatory).
I'd ideally like the kitchen/utility to be on its own, then split the current setup to be upstairs sockets and downstairs sockets. I'd also like extra sockets adding upstairs and down.
I'm currently replacing some floorboards upstairs so had a nose how it was wired. It's wired as upstairs sockets on a ring with each of the downstairs sockets spured from an upstairs socket. It looks like quite small conduit running down and I doubt you'd get another 2.5 T&E down to either create a ring or radial. Guess you could try with singles.
So what would be the best practical way about this? Obviously you could rip out the current conduit, fit bigger and run the wiring etc but obviously that would be a lot of mess (I think the mrs would like chasing kept to a minimum). Would you leave it how it is and put the extra sockets I want on a separate circuit instead? Just wondered if there's a simple answer as I've not come across this set up before.
Just interested in professional thoughts before I get some sparkys round.
Tailender Investor said:
So I would like some insight on how a sparky would go about this.
We moved in the new year and are now starting to get things done to the house. One area that needs work is the electrics.
I'm going to get a sparky to install a new CU, new Aico smokes, heat, CO etc. Put a separate CU in the garage for the garage.
However currently there are two MCBs for the house sockets. One for the kitchen, utility, the bedroom above the kitchen and the garage. Then one for for the rest of the house (3 other bedrooms, office, living room, dining room, conservatory).
I'd ideally like the kitchen/utility to be on its own, then split the current setup to be upstairs sockets and downstairs sockets. I'd also like extra sockets adding upstairs and down.
I'm currently replacing some floorboards upstairs so had a nose how it was wired. It's wired as upstairs sockets on a ring with each of the downstairs sockets spured from an upstairs socket. It looks like quite small conduit running down and I doubt you'd get another 2.5 T&E down to either create a ring or radial. Guess you could try with singles.
So what would be the best practical way about this? Obviously you could rip out the current conduit, fit bigger and run the wiring etc but obviously that would be a lot of mess (I think the mrs would like chasing kept to a minimum). Would you leave it how it is and put the extra sockets I want on a separate circuit instead? Just wondered if there's a simple answer as I've not come across this set up before.
Just interested in professional thoughts before I get some sparkys round.
either upgrade, to minimise the chasing... or actually bite the bullet and get it done to suit you. if it were me id be inclided to look at it as a rewire and get it done appropriately. whole house. sounds like a large house could look to split it to three rings, or have a kitchen ring and do the rest on radials. put in a decent car charger supply, work out what sockets your wanting, what IT kit you have as you may want to put in a UPS system in a central location. run your IT kit and also for your clocks and audio visual kit. We moved in the new year and are now starting to get things done to the house. One area that needs work is the electrics.
I'm going to get a sparky to install a new CU, new Aico smokes, heat, CO etc. Put a separate CU in the garage for the garage.
However currently there are two MCBs for the house sockets. One for the kitchen, utility, the bedroom above the kitchen and the garage. Then one for for the rest of the house (3 other bedrooms, office, living room, dining room, conservatory).
I'd ideally like the kitchen/utility to be on its own, then split the current setup to be upstairs sockets and downstairs sockets. I'd also like extra sockets adding upstairs and down.
I'm currently replacing some floorboards upstairs so had a nose how it was wired. It's wired as upstairs sockets on a ring with each of the downstairs sockets spured from an upstairs socket. It looks like quite small conduit running down and I doubt you'd get another 2.5 T&E down to either create a ring or radial. Guess you could try with singles.
So what would be the best practical way about this? Obviously you could rip out the current conduit, fit bigger and run the wiring etc but obviously that would be a lot of mess (I think the mrs would like chasing kept to a minimum). Would you leave it how it is and put the extra sockets I want on a separate circuit instead? Just wondered if there's a simple answer as I've not come across this set up before.
Just interested in professional thoughts before I get some sparkys round.
main board all RCBO's and get some surge arrestor units installed.
Lighting to suit and maybe a controller for that. make it suit your requirements.
ruggedscotty said:
either upgrade, to minimise the chasing... or actually bite the bullet and get it done to suit you. if it were me id be inclided to look at it as a rewire and get it done appropriately. whole house. sounds like a large house could look to split it to three rings, or have a kitchen ring and do the rest on radials. put in a decent car charger supply, work out what sockets your wanting, what IT kit you have as you may want to put in a UPS system in a central location. run your IT kit and also for your clocks and audio visual kit.
main board all RCBO's and get some surge arrestor units installed.
Lighting to suit and maybe a controller for that. make it suit your requirements.
What do you mean when you say upgrade?main board all RCBO's and get some surge arrestor units installed.
Lighting to suit and maybe a controller for that. make it suit your requirements.
I will be getting the CU upgraded. Going to get the biggest one that will fit so I have spare ways for future use. Currently things are wired off everything else and I'll get them put on their own RCBO. So things like the smokes, boiler, showers, garage etc will all be on their own breaker. The socket circuits I'm tempted to put on AFDD. Ideally I would like three socket circuits. Kitchen/Utility, upstairs and downstairs.
The previous owners have had some work done to the house (not to a good standard) mainly the kitchen. This has been rewired so there is a mix of brown/blue and red/black. We will be living here for quite a while so I'm definitely in the mindset of doing it properly now to what we want so we don't have to touch it again. We only have a 60A main fuse currently so when I'm getting the CU upgraded I will get bigger meter tails installed so I can upgrade to a 100A fuse. Then we are future proofed if we ever get an electric car etc.
I was more interested in the spurred downstairs sockets and how you'd get them on their own circuit. I guess it will either be try and get another cable/singles down the conduit. Or if that isn't possible then I guess the least intrusive option would be to keep the current breaker set up and then put the new sockets on their own breaker. So rather than having separate upstairs and downstairs circuits I'd have a mix of upstairs and downstairs on two breakers, so say two sockets per room on one and two on the other. I guess the positive of that is if a breaker trips then I'd still have some sockets in each room.
I have a question for an electrician, or whomever else may know the answer.
As part of a wider package of jobs, we had a local domestic electrician and his colleague round a few weeks ago. One of the (easier) jobs was to install a new light fitting in the hallway, however, the instructions were fairly adamant that it should be fixed to a joist, and i couldn't locate a joist anywhere near where the cable was popping out the ceiling. So I thought i'd leave it and bundle it together with the other jobs for the expert.
When they came to do it, they spoke amongst themselves, got it all prepped and ready to go - then they said to each other, as they felt the weight of the fitting wasn't that great, they would ignore the need for a joist and...here goes...."just fix it straight into the box". I didn't stand there staring at them, i was in the dining room 'working'. I noticed they drilled a new circular hole, but i didn't see what 'box' they put up there, how they put it up there, how the box is fixed in an empty ceiling void and what this so called box is.
Any ideas guys? I might need to repeat this for the upstairs hallway fitting.
As part of a wider package of jobs, we had a local domestic electrician and his colleague round a few weeks ago. One of the (easier) jobs was to install a new light fitting in the hallway, however, the instructions were fairly adamant that it should be fixed to a joist, and i couldn't locate a joist anywhere near where the cable was popping out the ceiling. So I thought i'd leave it and bundle it together with the other jobs for the expert.
When they came to do it, they spoke amongst themselves, got it all prepped and ready to go - then they said to each other, as they felt the weight of the fitting wasn't that great, they would ignore the need for a joist and...here goes...."just fix it straight into the box". I didn't stand there staring at them, i was in the dining room 'working'. I noticed they drilled a new circular hole, but i didn't see what 'box' they put up there, how they put it up there, how the box is fixed in an empty ceiling void and what this so called box is.
Any ideas guys? I might need to repeat this for the upstairs hallway fitting.
ruggedscotty said:
DT1975 said:
Hello sparkie(s)
We are looking at a new kitchen. We currently have two ovens off a 32 amp supply.
We are looking at adding an induction hob to add to the two ovens off the same supply.
One fitter saying its not an issue the other say he'd have to run a new cable from the fuse box which would be a right pain.
Any thoughts ? cheers
dont skimp...We are looking at a new kitchen. We currently have two ovens off a 32 amp supply.
We are looking at adding an induction hob to add to the two ovens off the same supply.
One fitter saying its not an issue the other say he'd have to run a new cable from the fuse box which would be a right pain.
Any thoughts ? cheers
You need to get the length of the cable run the expected load and calculate it from there. A good sparkie will give you the right advice here, this with ovens and hobs is that Id be wary as two ovens and your hob would probably not be reliable. work out the total load and even with a bit of diversity... need your Kw ratings of the hob and ovens to give you an answer.
New Induction hob rated 32amp / 7400 w, new ovens 13amp 2770w each.
I was given this answer elsewhere "A total of 12940W - equivalent to a stand alone cooker. however because cookers cycle on an off , diversity calculation of 10amp plus 30%of remainder .So 44 x 0.3 = 13.2 + 10 = 23.2 (plus 5 if there is a socket on the cooker switch). So current 32A is fine."
The run is about 20 feet, the issue is that they're quoting to remove all the coving (ceiling previously skimmed) replace it, skim the ceiling again, chase it down another wall which as you can imagine is bumping the cost up.
The problem is I can't argue the toss, it's been made clear take it leave it.
Very simple one but are you aware of any single module doorbell transformers that will suit a Wylex consumer unit? My board has one spare din rail space for it to sit in but the only Wylex transformer I can find has been discontinued so not sure it's a good idea to fit? Might not meet regs etc.
https://www.ebay.co.uk/itm/265012841014?mkevt=1&am...
Or is it ok to mix manufacturers within the CU? Some seem to say yes, others no. Not sure whether that's just electricians being pedantic though?
I know it's an expensive way of doing it and I could just put a separate transformer outside the unit, but I'd like to have it all in one place if possible.
https://www.ebay.co.uk/itm/265012841014?mkevt=1&am...
Or is it ok to mix manufacturers within the CU? Some seem to say yes, others no. Not sure whether that's just electricians being pedantic though?
I know it's an expensive way of doing it and I could just put a separate transformer outside the unit, but I'd like to have it all in one place if possible.
Edited by KnackeredOldBanger on Sunday 18th June 10:47
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