Panel calculation, panel change

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I see it as 1 riser, drop. From there you can have multiple meters and disconnects.

If we were talking about service calculations, would think we would need to take the Duplex into account for the main Service Drop. More than 1 100amp service.
 
jwelectric said:
Go back and read 220.82 again. Do part (B) first and then do part (C) and add the two together.

Edited to add from 220.82(A)
The calculated load shall be the result of adding the loads from 220.82(B) and (C).
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Ok Ill do it that way. But are u SURE this is how its suppose to be done?? ;)

water heater = 4500 watts
stove 42amps * 240 = 10080 watts
dryer 26 amps * 240 = 6240 watts
laundry (washing machine) = 1500 watts
appliance 2 circuits 1500 each = 3000 watts
lighting 780sqft * 3 va = 2340 watts

TOTAL 27660 watts
27660 - 10000 = 17660
17660 * 40% = 7064
Total 10000 + 7064 = 17064

heaters cadet 6000 watts
heaters cadet (for future) three (maybe 4) 1000 watt and one 2000 watt
6000 * 40% = 2400

17064 + 2400 = 19464

19464 / 240 = 81.1 amps Looks like the 100 amp panel should still work. :)
 
1793 said:
I see it as 1 riser, drop. From there you can have multiple meters and disconnects.

If we were talking about service calculations, would think we would need to take the Duplex into account for the main Service Drop. More than 1 100amp service.
Click to expand...

Yes you are correct. My mind frooze at the breaker and wasn't going to install anything other than the breaker.

With my last post one would think that I would have known that there would be some conductors involved.
 
brother said:
Ok Ill do it that way. But are u SURE this is how its suppose to be done?? ;)

water heater = 4500 watts
stove 42amps * 240 = 10080 watts
dryer 26 amps * 240 = 6240 watts
laundry (washing machine) = 1500 watts
appliance 2 circuits 1500 each = 3000 watts
lighting 780sqft * 3 va = 2340 watts

TOTAL 27660 watts
27660 - 10000 = 17660
17660 * 40% = 7064
Total 10000 + 7064 = 17064

heaters cadet 6000 watts
heaters cadet (for future) three (maybe 4) 1000 watt and one 2000 watt
6000 * 40% = 2400

17064 + 2400 = 19464

19464 / 240 = 81.1 amps Looks like the 100 amp panel should still work. :)
Click to expand...

Looks good to me. Now do the standard calculation.
 
jwelectric said:
Looks good to me. Now do the standard calculation.
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water heater = 4500 4500
stove 42amps * 240 = 10080(table 220.55 clm C) 8000
dryer 26 amps * 240 = 6240
Heaters 4 @1000 watts, 1 @2000 watts 6000
Total 24740

(Included in general lighting load)
laundry (washing machine) = 1500 watts
appliance 2 circuits 1500 each = 3000 watts
lighting 780sqft * 3 va = 2340 watts
TOTAL 6840 watts
6840 - 3000 = 3840
3840 * 35% = 1344
3000 + 1344 = 4344

24740 + 4344 = 29084 / 240 = 121 amps, Well did i do this standard calc right?? It seems to require bigger panel this way. Let me know if i missed anything. ;)
 
1793 said:
I see it as 1 riser, drop. From there you can have multiple meters and disconnects.

If we were talking about service calculations, would think we would need to take the Duplex into account for the main Service Drop. More than 1 100amp service.
Click to expand...

Let me clarify. there is only ONE service from the utility pole to the building. but there will be 2 SETS of service ENTRANCE conductors (connection from the service drop to the meter) . So 2 panels 2 weather overheads, 2 meters.

So there is only 1 service to the building. sorry about the confusion. Its just that ive some duplexes with just ONE SERVICE ENTRANCE CONDUCTORS comming down to the 2 meters. In that case you would need to calculate the whole duplex instead of just one side of it. :)
 
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brother said:
Let me clarify. there is only ONE service from the utility pole to the building. but there will be 2 SETS of service ENTRANCE conductors (connection from the service drop to the meter) . So 2 panels 2 weather overheads, 2 meters.

So there is only 1 service to the building. sorry about the confusion. Its just that ive some duplexes with just ONE SERVICE ENTRANCE CONDUCTORS comming down to the 2 meters. In that case you would need to calculate the whole duplex instead of just one side of it. :)
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Just for my own edification, what would be determining factors to install 2 separate risers, meters & panels, as opposed to 1 riser to trough then to 2 meters and panels?
 
1793 said:
Just for my own edification, what would be determining factors to install 2 separate risers, meters & panels, as opposed to 1 riser to trough then to 2 meters and panels?
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I just like to have things seperate as much as possible. If for some UNKNOWN 1 in a million reason we have to work on one unit and have the power off or do something with the meter, we can just disconnect that 1, and not mess with the other unit. Try not to inconvience the tenants as much as possible. I have been in situations where we had to do that. and it really dont cost that much more in overall cost when you do it this way. Its only 2 of them. :)
 
brother said:
WELL??? I did the STANDARD calculation, is it good?? ;) Where my Electrical Calculation teacher go?? LOL
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Now which one are you going to go with and why?

Here is a hint:
This section applies to a dwelling unit having the total connected load served by a single 120/240-volt or 208Y/120-volt set of 3-wire service or feeder conductors with an ampacity of 100 or greater.
 
jwelectric said:
Now which one are you going to go with and why?

Here is a hint:
This section applies to a dwelling unit having the total connected load served by a single 120/240-volt or 208Y/120-volt set of 3-wire service or feeder conductors with an ampacity of 100 or greater.
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Help me with this one. ;) I would LIKE to use the OPTIONAL method. the 100 amp panel.
Why?? Because when i did the STANDARD way i got OVER 100 amps.

So im curious about the INTERPERTATION of that section. Am i to interpert it means since i ORIGINALLY had a load using the standard method it gave me over 100 amps.?? or is it talking about it must be over a 100 amps for the OPTIONAL METHOD to be used. :)

I believe it would be ok for the original claim i make. ;)
 
brother said:
Help me with this one. ;) I would LIKE to use the OPTIONAL method. the 100 amp panel.
Why?? Because when i did the STANDARD way i got OVER 100 amps.

So im curious about the INTERPERTATION of that section. Am i to interpert it means since i ORIGINALLY had a load using the standard method it gave me over 100 amps.?? or is it talking about it must be over a 100 amps for the OPTIONAL METHOD to be used. :)

I believe it would be ok for the original claim i make. ;)
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Would it help to look at 230.77(C)?

Let's look at that sentence a little different.
This section applies to a dwelling unit having service fed with 120/240-volt and conductors with an ampacity of 100 or greater.
Does that sound like the same statement
.
 
jwelectric said:
Would it help to look at 230.77(C)?

Let's look at that sentence a little different.
This section applies to a dwelling unit having service fed with 120/240-volt and conductors with an ampacity of 100 or greater.
Does that sound like the same statement
.
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I think you meant 230.79 (C) ;) it helps. so was i right (correct me if im wrong). since no rating can be less than a 100 amps. but thats for ONE-family dwellings. So it should be ok to use the OPTIONAL method in doing this load calculation?? :)
 
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brother said:
I think you meant 230.79 (C) ;) it helps. so was i right (correct me if im wrong). since no rating can be less than a 100 amps. but thats for ONE-family dwellings. So it should be ok to use the OPTIONAL method in doing this load calculation?? :)
Click to expand...

Yes i did mean .79 instead of .77. This is good that you caught this.

I would us 100 amp panels.
 
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