3? Load Calculator

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cadpoint

cadpoint

Senior Member
Location
Durham, NC
SYSTEM VOLTAGE: 208/120V 3? 4W VOLT-AMPERES
CKT # DESCRIPTION CONNECTION AMPERES PF KW Line A Line B Line C
CN 1 1.00 0.120 120
3? 2 .90 0.648 240 240 240
BC 1 1.00 0.208 104 104
TOTALS: Err:508 Err:508 Err:508 Err:508
Amperes Conventional Err:509 Err:509 Err:509
Vector Err:508 Err:508 Err:508
Err:508 Err:508 Err:508
Neutral Err:508 TOTAL KVA
Err:508 Err:508

When I down loaded the second edit I think I some how changed the values of the attached tables...

Every down load since then has the same errors,
Err:508 starts above Conventional everything to the right and below is nothing but error

Open Office 4.1.1

I also get a note to update tables, and I say yes.
 
Smart $

Smart $

Esteemed Member
Location
Ohio
GoldDigger said:
BTW, do you use negative power factor for sources like GTIs?
Click to expand...
Not that I'm aware of.

Besides that, this is a load calculator. I didn't consider a source being a line item during development. Isn't a GTI is negative power from the perspective of a load? I'm thinking one would input negative amperes and a power factor of 1...???
 
Smart $

Smart $

Esteemed Member
Location
Ohio
cadpoint said:
SYSTEM VOLTAGE: 208/120V 3? 4W VOLT-AMPERES
CKT # DESCRIPTION CONNECTION AMPERES PF KW Line A Line B Line C
CN 1 1.00 0.120 120
3? 2 .90 0.648 240 240 240
BC 1 1.00 0.208 104 104
TOTALS: Err:508 Err:508 Err:508 Err:508
Amperes Conventional Err:509 Err:509 Err:509
Vector Err:508 Err:508 Err:508
Err:508 Err:508 Err:508
Neutral Err:508 TOTAL KVA
Err:508 Err:508

When I down loaded the second edit I think I some how changed the values of the attached tables...

Every down load since then has the same errors,
Err:508 starts above Conventional everything to the right and below is nothing but error

Open Office 4.1.1

I also get a note to update tables, and I say yes.
Click to expand...
Looks like the errors start on the Totals row...

The line item entry area, its headers (R2) and totals rows are an Excel "Table". Open Office may not support this feature either entirely, or in part (rather obvious it doesn't support the totals row). One of the advantages of this when one adds a new row, it automatically enters the formulas and associated properties in the cells. Without using the Table feature, one would have to do that manually (typically by copying).

I suppose I could work up a version that doesn't use a Table to see if it works for you. I also know Google Sheets doesn't support a couple functions used to perform vector calculations... so I'll try to change that too.
 
G

GoldDigger

Moderator
Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
Smart $ said:
Not that I'm aware of.

Besides that, this is a load calculator. I didn't consider a source being a line item during development. Isn't a GTI is negative power from the perspective of a load? I'm thinking one would input negative amperes and a power factor of 1...???
Click to expand...

I was just wondering why you made a point of setting the validation conditions to accept a PF anywhere between -1 and +1 instead of limiting it to the range from 0 to +1.
 
Smart $

Smart $

Esteemed Member
Location
Ohio
Smart $ said:
....

I suppose I could work up a version that doesn't use a Table to see if it works for you. I also know Google Sheets doesn't support a couple functions used to perform vector calculations... so I'll try to change that too.
Click to expand...
Non-Excel users try this version...

https://drive.google.com/file/d/0By0rzU3UuNh7RFp2UHBKQVc3amM/view?usp=sharing

"(nt)" in filename means non-table. This version also uses more common functions for vector calculations.

A word of caution for you users... Be sure when you add/insert rows to the line item area that you include the hidden columns.

Also recommend you add/insert rows in the midst of input rows, i.e. do not insert below bottom input row and copy down the formulas/formatting. This may result in the new rows being omitted from the totals.
 
Smart $

Smart $

Esteemed Member
Location
Ohio
GoldDigger said:
I was just wondering why you made a point of setting the validation conditions to accept a PF anywhere between -1 and +1 instead of limiting it to the range from 0 to +1.
Click to expand...
JIC (just in case) someone had a leading pf load. As you are likely aware, there technically is no such thing as a negative power factor. Both leading and lagging power factors are from 0 to 1. I just manipulated spreadsheet functionality so one can make a distinguishing entry. Whether phase shift is leading or lagging will affect vector calculations.

Now that you bring it up, perhaps one may want to enter a pfc bank as a load...???
 
Smart $

Smart $

Esteemed Member
Location
Ohio
NOTE: The reported neutral current is not to be construed as Code "maximum net calculated load between the neutral conductor and any one ungrounded conductor" of 220.61.
 
G

GoldDigger

Moderator
Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
Smart $ said:
JIC (just in case) someone had a leading pf load. As you are likely aware, there technically is no such thing as a negative power factor. Both leading and lagging power factors are from 0 to 1. I just manipulated spreadsheet functionality so one can make a distinguishing entry. Whether phase shift is leading or lagging will affect vector calculations.
Click to expand...
Yes, that pesky problem that power factor is cos(theta) and it is theta itself that is either in the range 0 to +PI/2 or 0 to -PI/2 depending on capacitive or inductive reactance (leading or lagging current)
Using the sign of PF instead to make that distinction really deserves a warning note in the spreadsheet somewhere.
 
Smart $

Smart $

Esteemed Member
Location
Ohio
GoldDigger said:
Yes, that pesky problem that power factor is cos(theta) and it is theta itself that is either in the range 0 to +PI/2 or 0 to -PI/2 depending on capacitive or inductive reactance (leading or lagging current)
Using the sign of PF instead to make that distinction really deserves a warning note in the spreadsheet somewhere.
Click to expand...
It's just one range:
LRV = -pi/2
URV = +pi/2

See comment in PF header cell... indicator is that little red triangle in its upper right corner. Comment should appear any time cursor is over that cell.
 
Smart $

Smart $

Esteemed Member
Location
Ohio
GoldDigger said:
...
Using the sign of PF instead to make that distinction really deserves a warning note in the spreadsheet somewhere.
Click to expand...
Revised. Deleted header comment and added input message (Data Validation, again) that appears every time a PF entry cell is selected.

Also note that Excel does not distinguish between 0 and -0. To enter a 'theory perfect' leading phase shift (90?), enter a negative infinitesimal value, e.g. -1E-100.

Excel users...
https://drive.google.com/file/d/0By0rzU3UuNh7a0tjUWc4TEtmcUE/view?usp=sharing

Non-Excel users...
https://drive.google.com/file/d/0By0rzU3UuNh7dXA4TlZWRUFsWnM/view?usp=sharing
 
Last edited:
mbrooke

mbrooke

Batteries Included
Location
United States
Occupation
Technician
Thank you!!!!!!!! :D:D:cool:

I calc panels all the time, this is a life saver! :thumbsup:


Just a tip, 347/600 and 240/415 for our Canadian folks, they count to :p
 
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