divemaster5734
Member
- Location
- Seattle
First, I have to say it is nice to see Mike's hard work produce these results.
I have used his code update classes for over a decade, but haven't had need to reach out to peers until now.
My question, I have a customer that has purchased an older commercial property and is going to turn it into a manufacturing facility.
They have around 130 separate pieces of equipment rated at 240V 1 phase.
Most is not rated at 230, or have a 208 listing.
I intended to call out a 3 phase Delta service, planning on phase balancing to take advantage of the increased PF.
Just got off the phone with the utility service planner, and while they admitted they didn't understand "the relationship with the high leg in poly phase applications", they definitely were Wye friendly.
I was not willing to accept the lower 208 Wye for multiple reasons.
The lowered efficiency of the 240 equipment, and then the increased overhead cost to the customer to overcome the lost efficiency.
He then said I would not actually see the increased work because I didn't actually have any 3 phase equipment.
At 208 I would have to increase the service to 800 A instead of 600.
OK, so now I'm doubting myself.
There will be 7 sub panels to a 600 A 3 phase Delta Panelboard.
I have the phases balanced to within 1%.
80198va is highest leg, and 79334 is lowest, and 79924 is the other.
A Delta service means one transformer, instead of the utility being able to use 3 and just having each phase out of sync enough to be separate.
To me, a single transformer would greatly increase my layout, because any phase that could not be perfectly balanced at an individual sub panel could then be corrected by adding load at a different phase on another sub panel, thereby correcting the loads across phases.
As for the high leg causing a reduced number of 120v circuits, that will not be an issue.
For this customer, there will be far more available spaces that they will ever need.
Am I correct, or am I missing something?
I'm supposed to have this application filed later today.
Thanks in advance.
I have used his code update classes for over a decade, but haven't had need to reach out to peers until now.
My question, I have a customer that has purchased an older commercial property and is going to turn it into a manufacturing facility.
They have around 130 separate pieces of equipment rated at 240V 1 phase.
Most is not rated at 230, or have a 208 listing.
I intended to call out a 3 phase Delta service, planning on phase balancing to take advantage of the increased PF.
Just got off the phone with the utility service planner, and while they admitted they didn't understand "the relationship with the high leg in poly phase applications", they definitely were Wye friendly.
I was not willing to accept the lower 208 Wye for multiple reasons.
The lowered efficiency of the 240 equipment, and then the increased overhead cost to the customer to overcome the lost efficiency.
He then said I would not actually see the increased work because I didn't actually have any 3 phase equipment.
At 208 I would have to increase the service to 800 A instead of 600.
OK, so now I'm doubting myself.
There will be 7 sub panels to a 600 A 3 phase Delta Panelboard.
I have the phases balanced to within 1%.
80198va is highest leg, and 79334 is lowest, and 79924 is the other.
A Delta service means one transformer, instead of the utility being able to use 3 and just having each phase out of sync enough to be separate.
To me, a single transformer would greatly increase my layout, because any phase that could not be perfectly balanced at an individual sub panel could then be corrected by adding load at a different phase on another sub panel, thereby correcting the loads across phases.
As for the high leg causing a reduced number of 120v circuits, that will not be an issue.
For this customer, there will be far more available spaces that they will ever need.
Am I correct, or am I missing something?
I'm supposed to have this application filed later today.
Thanks in advance.
