Anyone had a MIC upgrade on the ESB network?

2011

seaniefr wrote: »

The ELCB is not an over current device that function is carried out by the MCB.

Spot on.
The shower should be protected by an RCD (modern name ELCB) and an MCB or an RCBO (MCB & RCD combined in one unit).
To comply with the regulations an instantaneous type shower requires a dedicated RCD (it can't share an RCD with the sockets as shown in the photo).

2011

If the tails from the meter to the board were upgraded from a 10 to 16sq. it will not make any noticeable difference to voltage fluctuations. A larger ESB transformer would make the biggest difference.

Par1

You will get a volt drop when current increases its basic ohms law. Nothing to worry about. Its more noticeable when shower is switched on because 40+ amps are needed instantly.

Andy From Sligo

Par1 wrote: »

You will get a volt drop when current increases its basic ohms law. Nothing to worry about. Its more noticeable when shower is switched on because 40+ amps are needed instantly.I must say I didnt seem to notice it in my last house with 9kw shower, well for a split millisecond the lights may have dipped, but the lights didnt stay dimmed why the shower was on, i guess maybe our previous house had more regulated/smoothed out electricity or maybe higher voltage or higher MIC - mind you as I say our previous house was built in 2002 so maybe it had newer poles/overhead cables/ and a better transformer on the poles

Andy From Sligo

esb said if i give them my meter point number MPRN) and property address they will tell me what MIC is allocated for our house, so i will do that tomorrow, wont hurt to find out - If I read their price list right it costs over €1,180.00 to upgrade the MIC if I have got that right !

seaniefr

2011 wrote: »

Spot on.
The shower should be protected by an RCD (modern name ELCB) and an MCB or an RCBO (MCB & RCD combined in one unit).
To comply with the regulations an instantaneous type shower requires a dedicated RCD (it can't share an RCD with the sockets as shown in the photo).

Another issue that might crop up if the current regs were to be enforced:ZL values for mcbs/rcbo's and External earth loop impedance the further away an ESB Traffo is the further a fault current has to travel if that is added to 10mm Sq tails resistance and a smaller main earth conductor now someone really has a problem..........and if the ETCI were to say that the current regs (ET 101:2008 complete with amendments) were the only game in town then half the electrical installations in the country would fail as they keep reducing ZL values for mcbs and fuses and using more conversion factors with every new edition.....

seaniefr

Andy From Sligo wrote: »

esb said if i give them my meter point number MPRN) and property address they will tell me what MIC is allocated for our house, so i will do that tomorrow, wont hurt to find out - If I read their price list right it costs over €1,180.00 to upgrade the MIC if I have got that right !

Andy if they have to supply you just the basic 12kva it should be more than enough it sounds like they are under capacity for that area

Andy From Sligo

seaniefr wrote: »

Andy if they have to supply you just the basic 12kva it should be more than enough it sounds like they are under capacity for that area

if it is under capacity for the area who do you contact in the esb? and how do you get them to up the capacity for the area? - when i contacted ESB about the problem all they sent back was a link to an application form to upgrade MCU and a pdf of their charges

seaniefr

Andy From Sligo wrote: »

if it is under capacity for the area who do you contact in the esb? and how do you get them to up the capacity for the area? - when i contacted ESB about the problem all they sent back was a link to an application form to upgrade MCU and a pdf of their charges

No idea mate guess you could start by getting them to check what they are currently supplying you with and take it from there

Andy From Sligo

seaniefr wrote: »

No idea mate guess you could start by getting them to check what they are currently supplying you with and take it from there

Great, will do. Thanks for your help and the info.

kirving

braddun wrote: »

you open up the shower and take 2 leads off 1 heater

turn off power first


and use electrical tape to cover the 2 prongs

The
you should have lots of hot water


you will only use about 3.5kw

Why go messing about with the inside of the shower when you can just set it to the medium setting? Seems a bit crazy to me.

frankmul

seaniefr wrote: »

ESB are obligated to keep the supply to within 4% of 230v so 9.2 v below 230 v would be the limit?

The nominal voltage is 230 v. The esb have to supply it within 10% of that. The voltage supplied can drop to 207 before the esb need to act. The voltage dropping to 230 volts wouldn't be a big deal in my opinion. Most equipment would be designed to run on 220 - 240 volt supplies.
I'd be more concerned with the correct use of protection device.

2011

+1

As per EN50160 ESB Networks delivers electricity in a voltage range of 207 Volts to 253 Volts.
See link.

2011

frankmul wrote: »

I'd be more concerned with the correct use of protection device.

Exactly.

seaniefr

2011 wrote: »

Exactly.

ET 101:2008 525.2 says 4% of the nominal supply
am aware of the ESB requirement but how is something designed to operate at 230vac supposed to operate on 207vac?

2011

seaniefr wrote: »

ET 101:2008 525.2 says 4% of the nominal supply
am aware of the ESB requirement but how is something designed to operate at 230vac supposed to operate on 207vac?

I don't have the regulations in front of me, but I suspect that you are referring to volt drop, which is very different.

Can you quote that regulation? Thanks.

seaniefr

2011 wrote: »

I don't have the regulations in front of me, but I suspect that you are referring to volt drop, which is very different.

Can you quote that regulation? Thanks.

Will check when I get home 2011 it is about volt drop alright as far as I can remember I think it's worded as 4% of the nominal voltage

2011

seaniefr wrote: »

Will check when I get home 2011 it is about volt drop alright as far as I can remember I think it's worded as 4% of the nominal voltage

So what ET101 is saying is that the volt drop must not exceed a percentage of the nominal voltage. ESB Networks are saying that the nominal voltage is permitted to vary between 207 and 253 volts. Two very different issues.

Risteard81

2011 wrote: »

ESB Networks are saying that the nominal voltage is permitted to vary between 207 and 253 volts. Two very different issues.

Just to be accurate, the nominal voltage does not change as it is nominal. The presented voltage fluctuates. ESB probably have their transformer taps set to deliver at the higher end (i.e. around 253V) to allow for greater distances on the distribution network.

But regardless of what is seen we classify this as a 400/230V supply and calculate based on this.

2011

Risteard81 wrote: »

Just to be accurate, the nominal voltage does not change as it is nominal.

Agree totally.

My last post should read:

So what ET101 is saying is that the volt drop must not exceed a percentage of the nominal voltage. ESB Networks are saying that the noninal supply voltage is permitted to vary between 207 and 253 volts. Two very different issues.

Andy From Sligo

2011 wrote: »

+1

As per EN50160 ESB Networks delivers electricity in a voltage range of 207 Volts to 253 Volts.
See link.

207v is crazy especially if you have appliances to work between 230v-240v , i should imagine with a thing like a fat boil 3kw kettle if you ran it at 207vac then it would take longer to boil. they are running requirements set out in european standards but why cant they off their own back be more helpful close the gap anyway and offer 220v cut off point, so appliances and the like that are required to run at 220v-240v (or 250v) can run as they were manufactured to do. I dont think I have ever looked on a UK/Ireland appliance label and seen that the figure "Voltage: 207v - 250vac" ever!

I bet the pump on my shower would be better and more powerful as well if the voltage didnt drop so much when I put the shower on, ironically!

Andy From Sligo

evosteo wrote: »

the shower should not be connected directly off that 63a rcd, its over rated for the cable, it should be wired throught a 40a rcbo for personal safety due to the close proximity of the electric shower to water....

im not an electrician by trade, but isnt the point of an ELCB is to trip in milliseconds if there is a short to earth? - so is there really a relevance if its a 63a ELCB or a 40a ELCB .. its still going to trip (if it works properly) as soon as live (and / or neutral) comes into contact with earth isnt it?

Andy From Sligo

Just had another look at the consumer unit and actually the shower breaker in it is 32a should it be 40a MCB? (or 40aRCBO to be more correct?) - its an 8.5kw shower, it dont trip the 32a MCB though when the shower i on but isnt 8.5kw a bit heavy for 32a breaker ?

2011

Andy From Sligo wrote: »

im not an electrician by trade, but isnt the point of an ELCB is to trip in milliseconds if there is a short to earth? - so is there really a relevance if its a 63a ELCB or a 40a ELCB .. its still going to trip (if it works properly) as soon as live (and / or neutral) comes into contact with earth isnt it?

Let me try to explain:

ELCB or RCD
When a circuit if functioning correctly the current that flows down the live (generally referred to as the phase conductor) is equal to the current that returns on the neutral. An RCD measures the phase current and compares it to the neutral current. If the difference between these currents exceeds a certain threshold the device will operate (trip), disconnecting the circuit. Typically RCDs used in a domestic installation have an IΔn of 30mA. This means that if the difference between these two currents is >0.03 amps the unit will trip. If an RCD that is rated for 40A that means that it is designed to carry a maximum current of 40 amps indefinitely. It does not mean that it is designed to disconnect once the current increases beyond its rated value. In other words RCDs are not designed to provide "over current" protection.

Fuses and MCBs
These are much simpler devices to understand. They provide the over current protection referred to above. There are two types of over current, short circuit and overload. A short circuit is when there is very little resistance between a phase (live) and earth, a phase and neutral or between phases. When a short circuit occurs the current is very high (hundreds or thousands of amps) and this generally causes the fuse or MCB to operate quite quickly (sometimes milliseconds). However when a circuit experiences an overload condition it can take minutes or hours for the fuse or MCB to operate. How long it will take depends on many factors, but mainly the rating of the device (10, 20, 40 amps etc...), the "fusing characteristics" of the MCB or fuse (Google this to find the graph) and the magnitude of the current flowing.

RCBOs
These devices combine the features of an MCB and RCD into a single unit. So rather than installing a separate RCD and MCB for an instantaneous shower an electrical can install and RCBO. As well as requiring less connections this will take up less space in a distribution board. Commercial and industrial installations generally have an RCBO per socket circuit whereas domestic installations generally have a single RCD protecting all of the socket circuits within the installation. Although it is cheaper to have a single RCD protecting all of the socket circuits if this unit trips all of the sockets are lost.


So if a particular shower should draw 40A is not protected by an MCB then the over current device protecting it is the main fuse (generally 63A in a domestic installation) for the distribution board. This means that the shower could draw 70A for an extended period without the RCD tripping or the main fuse blowing :eek:

I hope this makes sense

dingding

That looks likee the original installation for a house that was built in the 80's.
The red and black cable, the meter and distribution board would all be typical of the time.

The house would have met the regulations at the time I would imagine.

At that time one ECB was used and sockets and shower wired through it.

I would say the issue is probably with the ESB supply (the distance from your transformer), however your voltage drop is within tolerances.

I cant see a case to upgrade your ESB supply.

2011

dingding wrote: »

I would say the issue is probably with the ESB supply (the distance from your transformer), however your voltage drop is within tolerances.

I cant see a case to upgrade your ESB supply.

+1

Therefore an non-issue in terms of volt drop.

2011

Andy From Sligo wrote: »

207v is crazy especially if you have appliances to work between 230v-240v

Why?

These appliances are designed to work with EN50160.
You will not find a house anywhere that has exactly 230 volts all of the time.

i should imagine with a thing like a fat boil 3kw kettle if you ran it at 207vac then it would take longer to boil.

Correct. The downside? It will take a couple of seconds longer to make a cup of tea, so what?

they are running requirements set out in european standards

Which are being met.

but why cant they off their own back be more helpful close the gap anyway and offer 220v cut off point

Because the loads presented to the transformer and the network is always changing, this causes the current to change which in turn causes the voltage to fluctuate.

so appliances and the like that are required to run at 220v-240v (or 250v) can run as they were manufactured to do.

What appliance to you have that is not running as it is supposed to?

I dont think I have ever looked on a UK/Ireland appliance label and seen that the figure "Voltage: 207v - 250vac" ever!

That is because the are not designed to run on an average of 207 or 250V.

Bruthal

Andy From Sligo wrote: »

207v is crazy especially if you have appliances to work between 230v-240v , i should imagine with a thing like a fat boil 3kw kettle if you ran it at 207vac then it would take longer to boil.

Why is it crazy? Waiting a few more seconds to make tea?

they are running requirements set out in european standards but why cant they off their own back be more helpful close the gap anyway and offer 220v cut off point, so appliances and the like that are required to run at 220v-240v (or 250v) can run as they were manufactured to do.

So if they offer 220v as the "cut off point" who will they get to alter the laws of nature/physics so the voltage cant possibly vary?

I dont think I have ever looked on a UK/Ireland appliance label and seen that the figure "Voltage: 207v - 250vac" ever!

Voltage rating on appliances is a nominal voltage. It would be a but silly to write the appliance is rated for a nominal voltage from 207 to 250. You won't likely see a sentence saying the average number of kids in Irish families is between 1 and 7.

I bet the pump on my shower would be better and more powerful as well if the voltage didnt drop so much when I put the shower on, ironically!

Well at least the reduction in pump flow rate might also have a reduction in element output power, keeping the temperature somewhat constant.

frankmul

Bruthal wrote: »

Well at least the reduction in pump flow rate might also have a reduction in element output power, keeping the temperature somewhat constant.

good point, I never thought about it like that.

Andy From Sligo

2011 wrote: »

Let me try to explain:

ELCB or RCD
When a circuit if functioning correctly the current that flows down the live (generally referred to as the phase conductor) is equal to the current that returns on the neutral. An RCD measures the phase current and compares it to the neutral current. If the difference between these currents exceeds a certain threshold the device will operate (trip), disconnecting the circuit. Typically RCDs used in a domestic installation have an IΔn of 30mA. This means that if the difference between these two currents is >0.03 amps the unit will trip. If an RCD that is rated for 40A that means that it is designed to carry a maximum current of 40 amps indefinitely. It does not mean that it is designed to disconnect once the current increases beyond its rated value. In other words RCDs are not designed to provide "over current" protection.

Fuses and MCBs
These are much simpler devices to understand. They provide the over current protection referred to above. There are two types of over current, short circuit and overload. A short circuit is when there is very little resistance between a phase (live) and earth, a phase and neutral or between phases. When a short circuit occurs the current is very high (hundreds or thousands of amps) and this generally causes the fuse or MCB to operate quite quickly (sometimes milliseconds). However when a circuit experiences an overload condition it can take minutes or hours for the fuse or MCB to operate. How long it will take depends on many factors, but mainly the rating of the device (10, 20, 40 amps etc...), the "fusing characteristics" of the MCB or fuse (Google this to find the graph) and the magnitude of the current flowing.

RCBOs
These devices combine the features of an MCB and RCD into a single unit. So rather than installing a separate RCD and MCB for an instantaneous shower an electrical can install and RCBO. As well as requiring less connections this will take up less space in a distribution board. Commercial and industrial installations generally have an RCBO per socket circuit whereas domestic installations generally have a single RCD protecting all of the socket circuits within the installation. Although it is cheaper to have a single RCD protecting all of the socket circuits if this unit trips all of the sockets are lost.


So if a particular shower should draw 40A is not protected by an MCB then the over current device protecting it is the main fuse (generally 63A in a domestic installation) for the distribution board. This means that the shower could draw 70A for an extended period without the RCD tripping or the main fuse blowing :eek:

I hope this makes sense

thanks for that - about as clear as mud lol - glad i never done an electricians course now

In my board though the shower is protected by a 32A and then the 63A Socket RCD/ELCB so by rights if the shower drew more than 32Amps it should trip the 32A MCB and if there is a leak to earth from phase or neutral then it should tip the 63A ELCB - have i got that bit right? .. if I havent im never gonna get it right!