120/480v meter

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Hfalz1

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Houston, Tx.
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Electrician
I'm looking at a meter for an office building and the meter says 120/480v what type of service is this? I'm used to 120/240V only.
 
Maybe usable for 120 to 480 volts. Would be very rare to have both voltages present at same time, and nearly impossible for an application using a typical 4 terminal meter.
 
Hfalz1 said:
Can i get 120/240 out or this type of service?
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A volt meter will tell you what you have.

If this is a meter driven by CT's it may be anything between 120 and 480 volts. Self contained metering seems would have a higher probability of being 120/240 single phase.
 
If it's a digital meter it may very well display the voltage as part of it's read out. But I agree you'll have to look at the wiring to know how many phases it is.
 
It has a black red and blue but the red wire is significantly smaller than the black and blue. I will test the voltage on Monday.
 
Id be interested in the B phase measurement to ground. Maybe nothing but fishy that its a different size..

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KnightPower said:
Id be interested in the B phase measurement to ground. Maybe nothing but fishy that its a different size..

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My guess it it is a high leg delta system, with minimal load on the high leg. You can reduce the size of that conductor - if you provide proper overcurrent protection. Circuit breaker with different rating for one pole then the others would be extremely rare, but you can put different fuses in a fused switch, even use fuse reducers if necessary.
 
kwired said:
My guess it it is a high leg delta system, with minimal load on the high leg. You can reduce the size of that conductor - if you provide proper overcurrent protection. Circuit breaker with different rating for one pole then the others would be extremely rare, but you can put different fuses in a fused switch, even use fuse reducers if necessary.
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It sounds weird to me because the smaller wire on one phase implies a 240/208/120V high leg system, but the red-black-blue color scheme usually means 208/120V wye.
 
ggunn said:
Only a voltage check will show for sure, but red-blue-black means 208/120 wye around here.
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Typical on older installs here would be red marking on high leg, and no marking on other lines, including white on the grounded conductor. No need to mark it, it lands on the grounded conductor bus because it is the grounded conductor, right?:)
 
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