How does Con Edison afford this?

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Hv&Lv said:
Sounds like two voltages.
stop and shops don’t need 277/480.
Home Depot heat and air system might like 277/480 better.
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I have done the design of MANY Home Depot retail stores and every one of them that I did use 480v. their prototype design, which they shared with their several architect / engineering firms nationwide, was based on 480v. they used it for lighting (mid 1990s they used 400 watt HID metal halide high bay fixtures - single phase 480 volts so they could put more fixtures on one 20 amp 480 - 1 circuit), parking lot lights (either 400 watt or 1000 watt HID), HVAC and, when required, fire pumps. In some markets, they even purchased their power at medium voltage (5KV nominal) and owned the 5KV - 480V transformer / medium voltage primary switch - when the discount rate for purchasing power at medium voltage offset the cost of transformer ownership.

Also, most of the newer grocery stores I have designed (Kroger, Fleming's, Kmart super centers, Pick N Save some "local" / "regional" chains, etc) all used 480v - although not often for the refrigeration racks, they learned (the hard way) that replacement motors for the refrigeration equipment, particularly in their rural locations were not readily available in 480 volt.
 
rlqdot said:
I have done the design of MANY Home Depot retail stores and every one of them that I did use 480v. their prototype design, which they shared with their several architect / engineering firms nationwide, was based on 480v. they used it for lighting (mid 1990s they used 400 watt HID metal halide high bay fixtures - single phase 480 volts so they could put more fixtures on one 20 amp 480 - 1 circuit), parking lot lights (either 400 watt or 1000 watt HID), HVAC and, when required, fire pumps. In some markets, they even purchased their power at medium voltage (5KV nominal) and owned the 5KV - 480V transformer / medium voltage primary switch - when the discount rate for purchasing power at medium voltage offset the cost of transformer ownership.

Also, most of the newer grocery stores I have designed (Kroger, Fleming's, Kmart super centers, Pick N Save some "local" / "regional" chains, etc) all used 480v - although not often for the refrigeration racks, they learned (the hard way) that replacement motors for the refrigeration equipment, particularly in their rural locations were not readily available in 480 volt.
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Right. And things like CVS in my area are 50/50.

Regarding those high bays around here they took advantage of the code. They would run a 30 or 50 amp 480 volt circuit- installed a 20 amp twist lock and fed the high bay off that. Safety chain was re-iterated in the design prints.
 
rlqdot said:
I have done the design of MANY Home Depot retail stores and every one of them that I did use 480v. their prototype design, which they shared with their several architect / engineering firms nationwide, was based on 480v. they used it for lighting (mid 1990s they used 400 watt HID metal halide high bay fixtures - single phase 480 volts so they could put more fixtures on one 20 amp 480 - 1 circuit), parking lot lights (either 400 watt or 1000 watt HID), HVAC and, when required, fire pumps. In some markets, they even purchased their power at medium voltage (5KV nominal) and owned the 5KV - 480V transformer / medium voltage primary switch - when the discount rate for purchasing power at medium voltage offset the cost of transformer ownership.

Also, most of the newer grocery stores I have designed (Kroger, Fleming's, Kmart super centers, Pick N Save some "local" / "regional" chains, etc) all used 480v - although not often for the refrigeration racks, they learned (the hard way) that replacement motors for the refrigeration equipment, particularly in their rural locations were not readily available in 480 volt.
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I don’t disagree with any of your statements.
he said it was a strip mall.
we serve many strip malls with two voltages.
the stop and shops here are convenience stores. 120/208.
grocery stores and Lowe’s, home depot, etc, all 480
 
Hv&Lv said:
I don’t disagree with any of your statements.
he said it was a strip mall.
we serve many strip malls with two voltages.
the stop and shops here are convenience stores. 120/208.
grocery stores and Lowe’s, home depot, etc, all 480
Click to expand...

True- but in pattern I see Con Ed paralleling the secondaries- so either 208 or 480- not both.
 
Hv&Lv said:
I don’t disagree with any of your statements.
he said it was a strip mall.
we serve many strip malls with two voltages.
the stop and shops here are convenience stores. 120/208.
grocery stores and Lowe’s, home depot, etc, all 480
Click to expand...


Alright, here is an example:

1581130966994.png



2,000 kva padmount vs two 2,000 kva transformers, two network protectors and a collector bus.
 
I wonder if this would make sense for EV charging, to make it easier for the utility to manage the loads during an emergency evacuation for example.
 
yuhong said:
I wonder if this would make sense for EV charging, to make it easier for the utility to manage the loads during an emergency evacuation for example.
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IMHO netowrks make it worse, because you can not selectively de-energize load. However, at the same time, spot networks provide significant reserve capacity when everything is in service.
 
yuhong said:
I wonder if this would make sense for EV charging, to make it easier for the utility to manage the loads during an emergency evacuation for example.
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For those who are unfamiliar, here is how Con Ed provides power and how its distributed in large buildings and officer towers:


1581167190827.png


Typically, under peak load, you can loose at least one or typically even two feeders and not overload the remaining transformers. In such an application it would make sense considering thousands of people at any given time may be in elevators, subways cars, ect.
 
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