Factor in 125% LCL for panel schedule

Status
Not open for further replies.

fandi

Senior Member
Location
Los Angeles
Hi All,
For a panel with only EV chargers load (which are LCL per NEC), does the load per phase (A, B, C) have to time 1.25?
Of course the feeder conductor size is 125% of the continuous load per 215.2(A) but I guess the VA consumed by the chargers is a fixed number even the car is charged more than 3 hours.
In other words, the feeder is sized per 215.2(A) but the total connected load of 90A (before multiply by 1.25) is acceptable for a 100A panel in my opinion.
Any inputs would be appreciated.
 
If you have 90 amps of load long-continuous load scheduled on the panel schedule you would need to add 25% the total on the panel would be 112.5A. A 100A panel would be undersized.
The feed to the panel does not need to be 125% of the panel, just 100%, or half-size under 100% if you are 800A or less. So a 200A bus panel with a 125A feeder/feeder breaker/and panel MCB would work.
Just a thought but there are dual-rate charger-pairs available, when both chargers operate the load on each is less than if either operated alone. In this case 100A could be fine.
 

fandi

Senior Member
Location
Los Angeles
If you have 90 amps of load long-continuous load scheduled on the panel schedule you would need to add 25% the total on the panel would be 112.5A. A 100A panel would be undersized.
Can you give me the code reference regarding adding 25% load to the schedule? I see NEC requires 125% for feeder sizing but I can't find NEC code section for adding 25% for LCL in the panel schedule. I thought LCL loads (lighting fixtures or EVs, etc.) still draw the same amps even at the first second of use or after 3 hours of use. They don't magically draw more amps after 3 hours.
 
Can you give me the code reference regarding adding 25% load to the schedule? I see NEC requires 125% for feeder sizing but I can't find NEC code section for adding 25% for LCL in the panel schedule. I thought LCL loads (lighting fixtures or EVs, etc.) still draw the same amps even at the first second of use or after 3 hours of use. They don't magically draw more amps after 3 hours.

I think there are many code sections that come into play. Including ones that talk about equipment like breakers and panelboards being 80% rated unless listed for operation at 100%.

215.3 Overcurrent Protection. Feeders shall be protected against overcurrent in accordance with the provisions of Part I of Article 240. Where a feeder supplies continuous loads or any combination of continuous and noncontinuous loads, the rating of the overcurrent device shall not be less than the noncontinuous load plus 125 percent of the continuous load

In 215.3 you have a feeder rated for your load let's say here it is 125A. If it fed a 100A panelboard that had no main breaker the panelboard would be unprotected (I'm not saying you don't need or want a main breaker). If you put a main breaker in the panel it would have to be 125A.

What you are saying about the load always being constant makes sense. However the problem is that most equipment is 80% rated.
 

fandi

Senior Member
Location
Los Angeles
I think there are many code sections that come into play. Including ones that talk about equipment like breakers and panelboards being 80% rated unless listed for operation at 100%.

215.3 Overcurrent Protection. Feeders shall be protected against overcurrent in accordance with the provisions of Part I of Article 240. Where a feeder supplies continuous loads or any combination of continuous and noncontinuous loads, the rating of the overcurrent device shall not be less than the noncontinuous load plus 125 percent of the continuous load

In 215.3 you have a feeder rated for your load let's say here it is 125A. If it fed a 100A panelboard that had no main breaker the panelboard would be unprotected (I'm not saying you don't need or want a main breaker). If you put a main breaker in the panel it would have to be 125A.

What you are saying about the load always being constant makes sense. However the problem is that most equipment is 80% rated.
Got it. Thanks a lot.
 
Status
Not open for further replies.
Top