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Looking to get an EV charger installed at some point in the near future. I need to go up through the loft, along the length of the house, and then down either the cavity, or externally out the gable wall, and down to the chargepoint (about 5m straight down),
My question is...can NYY-J (Hi-Tuff) be used externally for the run down the wall if I need to go that way? SWA is such a pain to run, and I know my sparky will appreciate terminating in Hi-Tuff over SWA (I haven't engaged the sparky yet, but keen to run the cable before I board out the loft).
Probably looking at 6mm (15-20m run) and fed off an RCD A (the sparky will be upgrading from Type AC).
My question is...can NYY-J (Hi-Tuff) be used externally for the run down the wall if I need to go that way? SWA is such a pain to run, and I know my sparky will appreciate terminating in Hi-Tuff over SWA (I haven't engaged the sparky yet, but keen to run the cable before I board out the loft).
Probably looking at 6mm (15-20m run) and fed off an RCD A (the sparky will be upgrading from Type AC).
ruggedscotty said:
BigBen said:
Teddy Lop said:
Problem you have is a 230v/9kW shower might be rated at 39.1 amps at 230v but with the 240-245v it's more likey to see 41-42 amps is what you're looking at and tripping the breaker is sometimes an issue. many a plumbers downfall when they think theyre replacing like for like but the old shower was a 240v rated unit. Safe is stick to 8.5.
As for the 10.5 again real current draw could be 48-49 amps.
as for 6mm ratings, clipped direct might be sufficient but a good spark should ask himself if being covered with rockwall by some ignoranious - which changes the rating dramatically - is a foreseeable risk.
Won't the current decrease with higher Voltage so 37.5A at 240V?As for the 10.5 again real current draw could be 48-49 amps.
as for 6mm ratings, clipped direct might be sufficient but a good spark should ask himself if being covered with rockwall by some ignoranious - which changes the rating dramatically - is a foreseeable risk.
amps is voltage divided by resistance... resistance stays the same. volts goes up then so does amps.
BigBen said:
ruggedscotty said:
BigBen said:
Teddy Lop said:
Problem you have is a 230v/9kW shower might be rated at 39.1 amps at 230v but with the 240-245v it's more likey to see 41-42 amps is what you're looking at and tripping the breaker is sometimes an issue. many a plumbers downfall when they think theyre replacing like for like but the old shower was a 240v rated unit. Safe is stick to 8.5.
As for the 10.5 again real current draw could be 48-49 amps.
as for 6mm ratings, clipped direct might be sufficient but a good spark should ask himself if being covered with rockwall by some ignoranious - which changes the rating dramatically - is a foreseeable risk.
Won't the current decrease with higher Voltage so 37.5A at 240V?As for the 10.5 again real current draw could be 48-49 amps.
as for 6mm ratings, clipped direct might be sufficient but a good spark should ask himself if being covered with rockwall by some ignoranious - which changes the rating dramatically - is a foreseeable risk.
amps is voltage divided by resistance... resistance stays the same. volts goes up then so does amps.
say
shower will be rated at a power.
that power will be assuming that shower is operating at duty which will be flow of water in at temperature and out at temperature so delta t with a flow rate and that gives a power to raise the water by that temperature.
the current pretty much stays the same to tell you the truth unless you change the flow rate etc. And the designer will have done the calculations to give that power to meet the requirements of the shower.
but we will design the electrical installation around that power figure as it would be safe to assume that would be the maximum power consumed.
given that the other variables are as expected.
ruggedscotty said:
the current pretty much stays the same to tell you the truth unless you change the flow rate etc.
Most power showers the temperature adjustment is a flowrate adjustment. The power output remains fixed regardless of flow or temp.Often they will have a 'high' and 'low' setting or a third 'eco' setting which does adjust the power, but no point in getting a more powerful one and not being able to turn it to high!
As said, they are just a resistive heater of fixed resistance, like a kettle, so as the voltage goes up, for a given resistance, the power and hence current goes up. Unlike a piece of electronics, where it might be a fixed power consumption, which if the voltage goes up the current goes down which is probably what the confusion is.
In the UK, the declared voltage and tolerance for an electricity supply is 230 volts -6%, +10%.
This gives an allowed voltage range of 216.2 volts to 253.0 volts. Most areas will be closer to 240v than 230v. I have seen 245v more than once.
ruggedscotty said:
You know how this stuff works ?
say
shower will be rated at a power.
that power will be assuming that shower is operating at duty which will be flow of water in at temperature and out at temperature so delta t with a flow rate and that gives a power to raise the water by that temperature.
the current pretty much stays the same to tell you the truth unless you change the flow rate etc. And the designer will have done the calculations to give that power to meet the requirements of the shower.
but we will design the electrical installation around that power figure as it would be safe to assume that would be the maximum power consumed.
given that the other variables are as expected.
Yes I know how stuff works. The thing I had not considered (and I thank you for explaining) is that you need to consider the Voltage at which the power of the shower (or other resistive load) is specified so your 9.0kW resistive load at 230V is in fact a 9.8kW resistive load at 240V.say
shower will be rated at a power.
that power will be assuming that shower is operating at duty which will be flow of water in at temperature and out at temperature so delta t with a flow rate and that gives a power to raise the water by that temperature.
the current pretty much stays the same to tell you the truth unless you change the flow rate etc. And the designer will have done the calculations to give that power to meet the requirements of the shower.
but we will design the electrical installation around that power figure as it would be safe to assume that would be the maximum power consumed.
given that the other variables are as expected.
BigBen said:
ruggedscotty said:
You know how this stuff works ?
say
shower will be rated at a power.
that power will be assuming that shower is operating at duty which will be flow of water in at temperature and out at temperature so delta t with a flow rate and that gives a power to raise the water by that temperature.
the current pretty much stays the same to tell you the truth unless you change the flow rate etc. And the designer will have done the calculations to give that power to meet the requirements of the shower.
but we will design the electrical installation around that power figure as it would be safe to assume that would be the maximum power consumed.
given that the other variables are as expected.
Yes I know how stuff works. The thing I had not considered (and I thank you for explaining) is that you need to consider the Voltage at which the power of the shower (or other resistive load) is specified so your 9.0kW resistive load at 230V is in fact a 9.8kW resistive load at 240V.say
shower will be rated at a power.
that power will be assuming that shower is operating at duty which will be flow of water in at temperature and out at temperature so delta t with a flow rate and that gives a power to raise the water by that temperature.
the current pretty much stays the same to tell you the truth unless you change the flow rate etc. And the designer will have done the calculations to give that power to meet the requirements of the shower.
but we will design the electrical installation around that power figure as it would be safe to assume that would be the maximum power consumed.
given that the other variables are as expected.
BigBen said:
ruggedscotty said:
You know how this stuff works ?
say
shower will be rated at a power.
that power will be assuming that shower is operating at duty which will be flow of water in at temperature and out at temperature so delta t with a flow rate and that gives a power to raise the water by that temperature.
the current pretty much stays the same to tell you the truth unless you change the flow rate etc. And the designer will have done the calculations to give that power to meet the requirements of the shower.
but we will design the electrical installation around that power figure as it would be safe to assume that would be the maximum power consumed.
given that the other variables are as expected.
Yes I know how stuff works. The thing I had not considered (and I thank you for explaining) is that you need to consider the Voltage at which the power of the shower (or other resistive load) is specified so your 9.0kW resistive load at 230V is in fact a 9.8kW resistive load at 240V.say
shower will be rated at a power.
that power will be assuming that shower is operating at duty which will be flow of water in at temperature and out at temperature so delta t with a flow rate and that gives a power to raise the water by that temperature.
the current pretty much stays the same to tell you the truth unless you change the flow rate etc. And the designer will have done the calculations to give that power to meet the requirements of the shower.
but we will design the electrical installation around that power figure as it would be safe to assume that would be the maximum power consumed.
given that the other variables are as expected.
Things like how the cable is mounted. What if anything covers it. there are alot of factors. what might be okay to begin with could quickly not be so okay.
Cable run length also needs careful consideration as your volt drop across the cable is important. The voltage at the load is only allowed to drop a certain %. that caught quite a few out that were installing hottubs when they were all the rage.
https://www.tlc-direct.co.uk/Technical/Charts/Volt...
have a look at this...
do the calcs for a few voltages @230v and 240v and even 250v and use some differing watts 6kw 8kw and 10kw... its an eye opener...
I am looking to extend my garage electrics (new build integrated garage which provided one double socket and two lights, which seem to be rated to the same as an Austin Alegro's headlight power).
Looking at the setup it is 2.5mm twin & earth straight from the Consumer unit into the double socket on the wall, then spurred off that is another 2.5mm twin & earth to a fused light switch. From the light switch is 1mm (assume twin &earth) up to two light fittings. The breaker to the circuit in the consumer unit is 16A for the Garage circuit.
Question: I want to extend the lighting to add in some jazzy garage lights by adding two more lights in. I also want to add three more double sockets into the garage also in different locations. The socket is in the middle of the back wall, and the light switch at the front right wall.
As the light switch is spurred off the already in place double socket, what is the best way to add the other sockets? Assume I want to keep them all in a serial (radial circuit?)
Also, is the breaker still good at 16A if I add these extra sockets, as assumption would be I could pull more Amps if everything plugged in and turned on?
Looking at the setup it is 2.5mm twin & earth straight from the Consumer unit into the double socket on the wall, then spurred off that is another 2.5mm twin & earth to a fused light switch. From the light switch is 1mm (assume twin &earth) up to two light fittings. The breaker to the circuit in the consumer unit is 16A for the Garage circuit.
Question: I want to extend the lighting to add in some jazzy garage lights by adding two more lights in. I also want to add three more double sockets into the garage also in different locations. The socket is in the middle of the back wall, and the light switch at the front right wall.
As the light switch is spurred off the already in place double socket, what is the best way to add the other sockets? Assume I want to keep them all in a serial (radial circuit?)
Also, is the breaker still good at 16A if I add these extra sockets, as assumption would be I could pull more Amps if everything plugged in and turned on?
RacingPete said:
Also, is the breaker still good at 16A if I add these extra sockets, as assumption would be I could pull more Amps if everything plugged in and turned on?
You could do that on any circuit. Just one double socket could have kit drawing 26A.Extra sockets on the radial gives you more convenience but doesn't let you run a higher load. But if most of the sockets are doing stuff like cordless tool chargers, that's unlikely to be a problem.
miniman said:
You can’t go above 16A on a 2.5mm radial really. Is there a route to get a chunkier feed into the garage? I’d put in a small consumer unit with a breaker for lighting and one for power.
Or are you saying the main house CU is in the garage?
CU is in the house, really only going to be used for charging power tools, vacuums, table saw, pillar drill etc. really it is just for convenience to have them else where. Though am thinking down the line to put in a two post lift. Or are you saying the main house CU is in the garage?
RacingPete said:
... really only going to be used for charging power tools, vacuums, table saw, pillar drill etc. really it is just for convenience to have them else where.
Just run some extra sockets and lights of what you have then. 16A radial with fused spur for lighting. Assuming the lighting is LED it will draw almost nothing. The only thing to be aware of, is that if you do trip the breaker, you will also be plunged into darkness.
Just something to o be aware of if you end up in their with a 2kw space heater, one bar electric fire, and an angle grinder.... Easily solved with a £20 battery backup emergency light.
I used to live in a late 80s built property with the garage fed by a 13A fused spur from the ring main running to garage via a section of SWA. There was a small CU on the wall with breakers for the lights and sockets. Perfectly fine for most things but in the winter the air compressor would often not start, presumably due to high current draw at start-up together with cold compressor and lubricating oil. Had to drag it to the front door and plug in in the hallway to get the first tankful and after that it was fine. So beware voltage drop on large-ish loads. Current garage has a 50A service so happy days.
How much would it cost to replace this CU with a current version? Property is for sale, so just needs to meet regulations and that's all.
The one pictured has broken flap hinges, it is plastic and is situated in an open area at knee height under stairs so I expect it will be raised by an electrical check. I assume the existing breakers cannot be re-used by moving them to an unpopulated CU box?
The one pictured has broken flap hinges, it is plastic and is situated in an open area at knee height under stairs so I expect it will be raised by an electrical check. I assume the existing breakers cannot be re-used by moving them to an unpopulated CU box?
Edited by gmaz on Wednesday 21st February 17:01
Edited by gmaz on Wednesday 21st February 17:12
gmaz said:
How much would it cost to replace this CU with a current version? Property is for sale, so just needs to meet regulations and that's all.
Does it need to, though?Buyer's surveyor/solicitor might demand an EICR and chip you on the estimated cost of any faults, but not meeting regs (past or present) shouldn't block a sale.
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