Would you code a 60 amp main switch been fed from a 100 amp BS1361

[Dave OCD]

There a four 3kw storage heaters on this board. So a load of 52 amps been drawn.

So the load is under the 60 amp rating of the main switch.

They'll most likely be 3.4Kw [or 2.55] so you're over 59 amps at 230volts if they're the larger heaters.

 

[davesparks]

I see your thinking now, so I won't code this.

Sometimes I need to stand back and look at what I'm seeing and thinking from a different angle.

Thank you for your advice.

Martin

Whether you code it or not is your decision.
When deciding on coding an observation you will find it helps to ask yourself the same questions I have done above. For C1 'what is the immediate danger here?', C2 'what is the potential danger?' for C3 'what improvement do I recommend/can this situation be improved?'

 

[davesparks]

They'll most likely be 3.4Kw [or 2.55] so you're over 59 amps at 230volts if they're the larger heaters.

But we don't have 230V supplies and the stated power of the heaters will be at 240V, the power dissipated will be less at 230V.

 

[Dave OCD]

Well 230v is the declared single phase voltage throughout the country now even though nothing has really changed [apart from the network becoming ever more stretched to the limit] so that's what we have to base calculations on, I see what you're saying about the heaters though.

 

[7029 dave]

I have never seen the voltage at 230v, and am measuring everyday, the lowest I have seen it is 235v. Never seen 216v, but 250v yes. 315v but that was ug fault lol

 

[davesparks]

Well 230v is the declared single phase voltage throughout the country now even though nothing has really changed [apart from the network becoming ever more stretched to the limit] so that's what we have to base calculations on, I see what you're saying about the heaters though.

That is not the declared voltage, it is the nominal voltage, something which some jobsworth in an office has written down and is impossible to implement. Nothing has changed because it cannot be changed, the whole country has substations with their output fixed at 250/433, there's nothing any jobsworth penpisher can do about that!
It doesn't change the basic physics though, If the stated power rating is at 240V you cannot just replace 240 with 230 in the calculation. The power dissipated will be less at 230V so the current which flows will be less.

 

[Risteard]

I have never seen the voltage at 230v, and am measuring everyday, the lowest I have seen it is 235v. Never seen 216v, but 250v yes. 315v but that was ug fault lol

Here I regularly measure bang on 230V.

 

[davesparks]

Here I regularly measure bang on 230V.

I thought I was measuring that kind of voltage around here a little while ago, my first reaction was to check the tester against another one, sure enough it had wandered off by around 10 volts and the actual voltage was >240

 

[Risteard]

Ironically the supply here was always 230V unlike the 220V in the south of Ireland and the 240V in Britain, and so harmonisation had no effect here!

 

[Dave OCD]

That is not the declared voltage, it is the nominal voltage, something which some jobsworth in an office has written down and is impossible to implement. Nothing has changed because it cannot be changed, the whole country has substations with their output fixed at 250/433, there's nothing any jobsworth penpisher can do about that!
It doesn't change the basic physics though, If the stated power rating is at 240V you cannot just replace 240 with 230 in the calculation. The power dissipated will be less at 230V so the current which flows will be less.

Yes DECLARED as the NOMINAL voltage, only because the distribution network is so stretched and it gives them more leeway, I often see low to mid 230s here in Cornwall. And what's a penpisher ? :wacko:

 

[davesparks]

Yes DECLARED as the NOMINAL voltage, only because the distribution network is so stretched and it gives them more leeway, I often see low to mid 230s here in Cornwall. And what's a penpisher ? :wacko:

If it has been declared as a nominal value then it is still only nominal! It has nothing to do with the **** state of the networks, the nominal voltage was changed to 230 by the penpushers in Europe, it was not changed to give anybody more leeway as the voltage has always been permitted to drop as low as 230.

It should have said penpusher

 

[Dave OCD]

Yes I know, and of course it's purely coincidence that they can get away with a lower voltage- it can quite legitimately be under 230 now, the network is in lovely condition.

 

[davesparks]

Yes I know, and of course it's purely coincidence that they can get away with a lower voltage- it can quite legitimately be under 230 now, the network is in lovely condition.

They aren't getting away with anything, the original lower limit was 225V

 

[Dave OCD]

Yes but now it's lower - obviously !