Old switchboard nametag interpretation

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anbm

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Existing ITE 240/120V single phase swbd, with (4) sections, see below.
Can someone explain to me why supply, section and neutral amp rating
are so different in each section tag???


MSBA.JPG


MSBA.PNGS1.JPGS2.JPGS3.JPGS4.JPG
 
Probably because each section was custom-built for the needs, more economical when everything is hand-assembled.
 
Are their multiple service disconnects? Looks like maybe #3 is the incoming/metering section and that feeds out to 3 service disconnects in the two sections to the left and the right section which has two service disconnects? In that case the numbers would be reasonable ITs pretty common to have section buss less than supply buss
 
electrofelon said:
Are their multiple service disconnects? Looks like maybe #3 is the incoming/metering section and that feeds out to 3 service disconnects in the two sections to the left and the right section which has two service disconnects? In that case the numbers would be reasonable ITs pretty common to have section buss less than supply buss
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There are (5) service disconnects - section 1 has 1, section 2 has 2 and section 4 has 2. Each service disconnect to feed one meter center or tap can. What I do not understand is, for example section-2 label: 3000A supply, 2000A section, 1600A neutral. Should the Amp. be same?
 
anbm said:
There are (5) service disconnects - section 1 has 1, section 2 has 2 and section 4 has 2. Each service disconnect to feed one meter center or tap can. What I do not understand is, for example section-2 label: 3000A supply, 2000A section, 1600A neutral. Should the Amp. be same?
Click to expand...
No, supply or thru buss is usually larger than the section buss. Neutral buss is clearly downsized because it doesn't need to be full size. Note there is no 408.36 for switchboards, and they are often designed more around actual loads on each component, so the ratings May often get lower as you move through the switchboard.
 
electrofelon said:
Note there is no 408.36 for switchboards, and they are often designed more around actual loads on each component, so the ratings May often get lower as you move through the switchboard.
Click to expand...
The switchboard in the OP is at least 40 years old. Switchboards standards have change since then.
 
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