Elecestim123
Member
- Location
- MN
- Occupation
- Electrical Estimator
Trying to understand if I'm missing something, or if the engineer has something wrong.
On the set of drawings I'm working on now for an estimate, the equipment schedule states to provide 208V, single phase/SINGLE POLE (20/1 breaker) power to some equipment. The equipment is fed from a 208/120V panel. On the panel schedule in this panel, phases A,B, C are supplying loads as normal for 120V/208V throughout, including 3 phase 208V.
How would 208V be fed from a single pole (20/1) breaker in this case?
Trying to remember back to my electrical theory days, I know there's such thing as a Delta High Leg system, but isn't that a 240V system that can also supply 208V and 120V? And typically the high leg would be the "B" phase or "C phase I believe. So from any phases to any other phase, I get 240V. If I go from high leg to neutral, I get 208V. If I go from neutral to any phase (besides the high leg), I get 120V.
But that can't be the system being used in this case, because both B and C phases in the panelboard schedule are shown supplying 120V equipment/receptacles. So, if the Engineer designed off a Delta High Leg system, I could see how I can get 208V single pole. But this can't be Delta High Leg configuration because of the 120V I mentioned above.
Otherwise is there such thing as a 208V Delta High Leg system, or does Delta High Leg only come in 240V?
Therefore I'm struggling to understand how I could get 208V off 1 pole as the panelboard shows for equipment, as opposed to it being 2-pole. If the engineer has it wrong that's obviously going to shake things up quite a But. Just want to understand before I bring any points up to the Engineer/Vendors
Thanks in advance!
On the set of drawings I'm working on now for an estimate, the equipment schedule states to provide 208V, single phase/SINGLE POLE (20/1 breaker) power to some equipment. The equipment is fed from a 208/120V panel. On the panel schedule in this panel, phases A,B, C are supplying loads as normal for 120V/208V throughout, including 3 phase 208V.
How would 208V be fed from a single pole (20/1) breaker in this case?
Trying to remember back to my electrical theory days, I know there's such thing as a Delta High Leg system, but isn't that a 240V system that can also supply 208V and 120V? And typically the high leg would be the "B" phase or "C phase I believe. So from any phases to any other phase, I get 240V. If I go from high leg to neutral, I get 208V. If I go from neutral to any phase (besides the high leg), I get 120V.
But that can't be the system being used in this case, because both B and C phases in the panelboard schedule are shown supplying 120V equipment/receptacles. So, if the Engineer designed off a Delta High Leg system, I could see how I can get 208V single pole. But this can't be Delta High Leg configuration because of the 120V I mentioned above.
Otherwise is there such thing as a 208V Delta High Leg system, or does Delta High Leg only come in 240V?
Therefore I'm struggling to understand how I could get 208V off 1 pole as the panelboard shows for equipment, as opposed to it being 2-pole. If the engineer has it wrong that's obviously going to shake things up quite a But. Just want to understand before I bring any points up to the Engineer/Vendors
Thanks in advance!
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