ElectDesigner
Member
- Location
- Ontario, Canada
I just wanted to share a problem some one told me last week, so this engineer specified a 1200A switchboard (for a retail project) but forgot to indicate the metering compartment on the swbd in the single line diagram, the job gets tendered and ready for construction, contractor sends shop drawings and engineer realizes he forgot about the metering section.
My question is what options does the engineer or designer have at this stage with minimal cost implications? This is a breaker swbd, and if I remember correctly the metering should be done right after the main breaker, currently the swbd on the shop drawings has a main breaker with breakers for HVAC units and downstream distribution panels. I would imagine it would be hard to add current transformers to the bus after the main breaker, unless this is done externally - not sure what the code implications are for this.
In this case would a new board have to be ordered ? Just wanted to hear some experiences.
I have seen instances in shopping malls where they ran out of space on a swbd and connected a disc. sw (or safety switch) to the main bus, but this is not really metering issue.
My question is what options does the engineer or designer have at this stage with minimal cost implications? This is a breaker swbd, and if I remember correctly the metering should be done right after the main breaker, currently the swbd on the shop drawings has a main breaker with breakers for HVAC units and downstream distribution panels. I would imagine it would be hard to add current transformers to the bus after the main breaker, unless this is done externally - not sure what the code implications are for this.
In this case would a new board have to be ordered ? Just wanted to hear some experiences.
I have seen instances in shopping malls where they ran out of space on a swbd and connected a disc. sw (or safety switch) to the main bus, but this is not really metering issue.