MFD Calcs

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rp9ball

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Load Calcs for 72 unit MFD.
Do these look correct? No Electrical Specs. Design Build.
Owner requires each unit to be separately metered.
We are proposing a 2000A 208/120V service.
Thanks in advance for your input.
 

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  • MFD Elec Load Calcs.pdf
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Some quick observations:

72 units ? 2 SABC/unit = 144... you only show 114?

Laundry and dryers only shows 8 circuits, yet no house laundry???

It appears you are basing your dryer and range calculation on 220.54/55 [via 220.14(B)]. You cannot do that using the optional method [220.84(C)(3)(b)&(c)]. You have to sum the nameplate data: sum kW = sum kVA.

Conventional method for applying demand is to the VA amount, not to the converted-to-amperes amount.
 
SABC's

SABC's

Some quick observations:

72 units ? 2 SABC/unit = 144... you only show 114?

Laundry and dryers only shows 8 circuits, yet no house laundry???

It appears you are basing your dryer and range calculation on 220.54/55 [via 220.14(B)]. You cannot do that using the optional method [220.84(C)(3)(b)&(c)]. You have to sum the nameplate data: sum kW = sum kVA.

Conventional method for applying demand is to the VA amount, not to the converted-to-amperes amount.

This an RCAC facility. Not all apartments have SABC's.

Washers and dryers are house loads.

So for the dryers, I do not need to figure per phase. Just sum and apply demand?

Thanks :happyyes:
 
This an RCAC facility. Not all apartments have SABC's.

Washers and dryers are house loads.

So for the dryers, I do not need to figure per phase. Just sum and apply demand?

Thanks :happyyes:
I don't know what an RCAC facility is specifically or how it relates to Code calculations. Are you saying some apartments do not have a kitchen counter or SABC qualifying areas... amounting to less than two SABC's per unit? It is possible... just not normal for full-fledged apartments.

If the dryers are house loads, you would figure them per 220.54 but you can't include them in the apartment optional calculation and apply demand. You have to put them under house load calculation.
 
MFD Calcs updated

MFD Calcs updated

I have attached revised the calcs. :?

RCAC = Residential Care Apartment Complex. Our state classification for that is a MFD.

Yes some apartments do not have SABC's as they are only 350 sq ft (Bed, bath, and living room only)

Thanks
 

Attachments

  • Revised MFD load calcs.pdf
    35.7 KB · Views: 0
Assuming dryers are 1?...

Dryers6 5,000
Max/?2 10,000
3? equivalent10,000 ? 2 ? 3 15,000
220.54 Demand 75% 11,250
 
Load Calcs for 72 unit MFD.
Ignorant Brit here......again.
MFD?
Multi-function dwelling?

Just asking.
I've learned loads here - ufer, emt, pecker head, stuff like that.
But I bet you don't know what a zebedee is....
 
Ignorant Brit here......again.
MFD?
Multi-function dwelling?
I understood to mean microfarad. In this context and the texting world we live in I suspect it stands for Multi Family Dwelling.


Just asking.
I've learned loads here - ufer, emt, pecker head, stuff like that.
But I bet you don't know what a zebedee is....
I don't. I know what a boot and a loo is.
 
I understood to mean microfarad. In this context and the texting world we live in I suspect it stands for Multi Family Dwelling.
I don't. I know what a boot and a loo is.

You have unistrut?

P3300.jpg

A zebedee is the spring/washer attachment that fits inside.
Zebedee was a character in the childrens' cartoon series, The Magic Roundabout.

http://en.wikipedia.org/wiki/The_Magic_Roundabout

Hence the spring thing.
So I have reciprocated by addeding a rich bit of arcane culture to your already comprehensive knowledge of Brit speak...........:D
 
Assuming dryers are 1?...

Dryers6 5,000
Max/?2 10,000
3? equivalent10,000 ? 2 ? 3 15,000
220.54 Demand 75% 11,250
Ooops.... must have experienced a precursory senior moment on that one. Should have been...

Dryers65,000
2 ? Max/?420,000
3? equivalent20,000 ? 2 ? 330,000
220.54 Demand 75%22,500

...which is exactly what you had to begin with. The method would have made a difference if there was an imbalanced number of dryers per phase.
 
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