**Show Us Your Installs!!!**

[Knobhead]

Picture 9, is that a dual bus-bar sytem?

 

[Outspoken]

Picture 9, is that a dual bus-bar sytem?

Yes Tony, two separate feeds from separate Tx's via individual Rotary UPS systems with auto changeover in the event of failure, and this is all backed up by individual LV Gen sets but the site also has 15MVA 11kV generating capacity in case we lost the feeds from the outside world..

Here are those other pictures I mentioned in email Tony..




Bear in mind these are snagging pictures so these are not finished items, all the cables require identifiers attached, including the HV or they need tidying in some way, but they are OK for what you need Tony.

The comms in the top 4 pics is the HV/LV monitoring/switching infrastructure that also runs the live mimic boards we have for ACB and MCCB positions and status

 

[Knobhead]

Now I’m retired I envy you.

Heavy power alongside plant control PLC programming were my favourites.

 

[High Tower]

Nice to see this kind of stuff, it's well above the kind of stuff I do!! And it's nice to see people taking such pride!

 

[Tsakitsan]

And because I want to keep my last promise, that I will upload some more college-level ART! (Yes! I consider it art! )
Here are some 20mm A1 ring final circuit installation. The conduit is 20mm seam welded galvanised heavy gauge steel. And the sockets boxes are metal clud surface (MK logic+ I think). For the trainees like me: The A1 ring final circuit should have 2.5mm cable with a 32amperes BS60898 type B circuit braker, and it can potentially cover 100m^2 of space.
Oh I forgot to mention that we have a switched fused connection unit too.. But it does ΝΟΤ feed an appliance.



Sorry for any mistakes and thank you!

 

[Outspoken]

Couple of observations;

1. The layout of the conduit should have been considered so that they did not need to cross
2. Conductor length needs attention, if you look at one of the browns in the spur you can see where it has been rubbed when the faceplate screwed back.

I appreciate a lot comes with experience, but it's things like the scuffed cable that can cause you problems both in college and the real world, I would be none to impressed when testing a new install to find that.

 

[High Tower]

Couple of observations;

1. The layout of the conduit should have been considered so that they did not need to cross
2. Conductor length needs attention, if you look at one of the browns in the spur you can see where it has been rubbed when the faceplate screwed back.

I appreciate a lot comes with experience, but it's things like the scuffed cable that can cause you problems both in college and the real world, I would be none to impressed when testing a new install to find that.

From what I remember, they must cross as part of the assessment, and a large portion of the marks are dependent on your ability to set the conduit neatly

 

[High Tower]

A couple of things.......

If you were to leave a little more length in the CU then you would be able to get the cables a little neater.

The fly leads in the accessories shouldn't be coiled

You do not really need the fly leads as you have cpc's run in and the conduit is earthed at the CU, and the back boxes are fixed lug. The only time you really need fly leads is if you have no cpc's and you are using the conduit as your means of earthing.

These are just pointers and are not criticisms!!, overall it's a nice install and a bloody good job compared to a lot of college work I see!

 

[Outspoken]

From what I remember, they must cross as part of the assessment, and a large portion of the marks are dependent on your ability to set the conduit neatly

You have a point there High Tower, its been a very long time since I was at college, should have considered that!

 

[Engineer54]

I would be asking, why you have pulled CPC's into a galvanised conduit system in the first place?? All your achieving there, is filling up the conduit with needless copper!! lol!

 

[Billythekid]

I would be asking, why you have pulled CPC's into a galvanised conduit system in the first place?? All your achieving there, is filling up the conduit with needless copper!! lol!

Not this again!

Unfortunately it's true, this is common practice now. You don't need to tell me why it's un-neccessary/stupid/borderlining criminal (cost wise), as I already know - this is merely what clients/designers/specs ask for. I've questioned their reasoning/sanity many a time, nearly always told "just incase", or "that's how they want it". Colleges/Training centres are obviously employing the same tactics now.

The mind boggles.

Regards

Billy

 

[Engineer54]

Then they are all bloody idiots!! ''Just in Case'' has no relevance in electrical design concepts!!

 

[pennywise]

Then they are all bloody idiots!! ''Just in Case'' has no relevance in electrical design concepts!!

So why would redundancy be built into some installations, other than for "just in case" situations

 

[STONEZZZ]

Started new job today....lots of trunking, tray, conduit, basket, skirting trunking,dado, ect ect ect .
and I have to fit all this in a 100mm space above a suspend ceiling!

 

[STONEZZZ]

Here are some more pics..... Finished at the end of August ...

 

[Knobhead]

What is it?

Is there a prize for the first correct answer?

 

[Billythekid]

Then they are all bloody idiots!! ''Just in Case'' has no relevance in electrical design concepts!!

Couldn't agree more!

I see your point, but would argue (forgetting relevant Laws/Guidance) that a very high percentage of design is for "just in case" scenarios. Fire Alarms, Intruder Alarms, Controls, Cut-outs, E-stops, UPS, back up Generators, less abled alarms, could all be placed in the "just in case" bracket.

I like this "nanny" state of affairs as little as the next man. . .

If you can't work out that it's raining or dark, should you be driving?
Yet vehicles are coming equipped with rain/light sensors.

If you are unable to recognise if you remove a smoke alarms supply that it will no longer operate, do you deserve to live?
Yet we go to great lengths to ensure the supply will remain on, and install back up batteries.

If we carry on supporting this then our already sullied gene pool is going to become a whole lot worse!

When does it stop being a "life safety system", and become a "they are clearly imbeciles, lets protect them from their own stupidity", or indeed "just incase"?

Was it you or Tony that wrote "never underestimate the ingenuity of a stupid person"? Unfortunately this could not apply more to design - "just incase".

Regards

Billy

 

[Engineer54]

but would argue (forgetting relevant Laws/Guidance) that a very high percentage of design is for "just in case" scenarios. Fire Alarms, Intruder Alarms, Controls, Cut-outs, E-stops, UPS, back up Generators, less abled alarms, could all be placed in the "just in case" bracket.

You'd be wrong, each of these systems quoted, have their own laid down design criteria's, And again the ''Just in Case'' aspect, has no relevance within those laid down design and risk assessment concepts...

 

[Engineer54]

Started new job today....lots of trunking, tray, conduit, basket, skirting trunking,dado, ect ect ect .
and I have to fit all this in a 100mm space above a suspend ceiling!

I can't see a single item of the above in these photo's!! lol!!

 

[Outspoken]

Then they are all bloody idiots!! ''Just in Case'' has no relevance in electrical design concepts!!

It's designed into the spec of an installation, "Just in case" some numpty who thinks he knows it all and more than the Regs comes along and replaces a section of steel conduit with plastic because it's easier or gets around the problem of threading a section that may be installed through a floor etc..

Don't say it doesn't happen, seen it way too many times.

Further, Reg 543.2.7 states

"Where the protective conductor is formed by metal conduit, trunking or ducting or the metal sheath and/or armour of a cable, the earthing terminal of each accessory shall be connected by a separate protective conductor to an earthing terminal incorporated in the associated box or other enclosure"

Therefore a fly lead would need to be added to all accessory boxes within the conduit system, but what happens when you then introduce connections via flexible conduit, do you rely on a connection to the rear of a BESA box to provide your circuit earth? Great in theory, but many installation get abused, especially flexible conduit connections, and this could get damaged.

Further, Reg 543.2.9 states

Except where the circuit protective conductor is formed by a metal covering or enclosure containing all of the conductors of the ring, the circuit protective conductor of every ring final circuit shall also be run in the form of a ring having both ends connected to the earthing terminal at the point of origin of the circuit.

Now I can envisage plenty of scenarios whereby the conduit may not be continuous, such as when you use the conduit system to feed several rings and one or more actually terminate in Dado trunking, which being plastic is not good as a CPC. This creates a discontinuous metal cpc and thus to comply with the regs you would have to run a separate CPC into the circuit in this situation. You also need to be aware that perhaps the metal is not continuous in all instances and it is possible that in the future the metal conduit system could be broken into and thus become discontinuous.

Lastly, is it really that much of an issue to pull in a separate earth when your pulling cables in anyway? At least you know for sure you have a compliant cpc.