comercial supply with generator mixed

[razz]

hello , we have a canteen building which is fed by a 160amp 3 phase pme supply , the trouble is , we have no spare capacity to provide extra electrical heating . what are the rules regarding running electric heaters with in this building from a seperate generator , regarding earthing etc , thanks loads

 

[Knobhead]

Gas heaters would be cheaper

 

[Engineer54]

How do you know your present 3ph 160A supply is out of capacity?? Must be a dammed big canteen!! Is this canteen in an industrial/commercial situation?? If so, run a new supply from the main or sub-distribution board. Running a generator all day to supply heating loads would be pure folly!! ie cost of generator, fuel/running costs, maintenance costs etc....

As Tony stated, it'll be far more cost effective to install a gas/oil heating system...

 

[malcolmsanford]

Have a look at section 551.7 of the Regs. Though not 100% appropriate to what you want, and to be honest I don't think I have ever seen a set up where a section of the installation is supplied by the DNO and another section supplied by an independent generator.

I'm sure your going to get some grief from the HSE over this, unless you are going to be labeling the bejesus out of everything, and the DNO are going to want clear and concise evidence that your system is not going to back feed into theirs ............

And this is before we go down to dual supplies etc etc ......................

 

[razz]

thanks for the replys dudes , its a school and we monitor our supplys and loads , we peak at 180amp per phase , we can not have anymore from our local substation as that is overloaded also , had a peak thru the door when it packed up last time with the EDF man , was an amazing sight to see , we are waiting for a substation to be build on site , but thats a long way away . good shout on the gas heaters , cheers razz

 

[Engineer54]

thanks for the replys dudes , its a school and we monitor our supplys and loads , we peak at 180amp per phase , we can not have anymore from our local substation as that is overloaded also , had a peak thru the door when it packed up last time with the EDF man , was an amazing sight to see , we are waiting for a substation to be build on site , but thats a long way away . good shout on the gas heaters , cheers razz

Ah, ...the way you worded your OP, made it sound as if the 160A supply was for the canteen, not the whole installation!! ...lol!! Your going to be pretty stuffed then, or advise the school to use an alternative energy source!! I would have thought that most schools had a commercial sized boiler(s) for there heating requirements, always used too anyway??

 

[razz]

the 160 3ph is just for our canteen , the dishwasher alone takes 100amp 3ph and is the size of a transit van , we now looking at distratification fans , not sure if thats spelt correct , and gas heating . we are an old school and the poor heating system is flat out in that building , but can`t cope , we have had prices in to renew this but the boss had heart failure , razz

 

[Engineer54]

the 160 3ph is just for our canteen , the dishwasher alone takes 100amp 3ph and is the size of a transit van , we now looking at destratification fans , not sure if thats spelt correct , and gas heating . we are an old school and the poor heating system is flat out in that building , but can`t cope , we have had prices in to renew this but the boss had heart failure , razz

A 100A 3 ph dishwasher?? How big is this school, most decent sized factory canteens wouldn't require a dishwasher of that size/capacity?? What's your boss having heart failure for, is it coming out of his personal bank account? lol!!

Seems like your boss is living in false economy mode. If the boiler is going flat out and can't cope with it's present load, then it must be costing the school a small fortune in running and maintenance costs. I bet the cost of a new correctly sized unit will be off set by the far more economical running costs of a new boiler, over what must be now, a totally inefficient boiler!!!

 

[razz]

we pass 1000 kids thru an hour at peak , the dishwasher salesman did his job on that one . believe it or not , the heating boilers are fairly new , but were incorrectly sized i recon , but as usual i`m too far down the line to be told much more