A while back I was on a trip to Mexico and was checking out some electrical projects as well as got to see the code there.
Its based on the NEC and yeah yeah yeah its not always followed, but on big project's it is.
What I found interesting is in recent years the only two grid operators merged into one, and I don't know all the details but one used 220Y/127 and the other our 208Y/120 and they standardized on the 220Y/127 distribution.
They often serve customers from large three phase 220Y127 distribution transformers, customers are limited to a service of something like 60 Amps at single phase open wye (127/220), a small commercial building or even a farm that needs over 60 amps will often have this 220Y/127 three phase.
Many small residential customers in cities to villages still are on what appear to be 30A 127V two wire services.
Rural areas with only a line and neutral primary do have split phase 120/240 transformers.
I saw the nameplate of some equipment and it was in fact '127V' not the 120 or 115 or 117 I normally see here.
So I got interested and checked some more equipment and yeah most were '127'
I imagine in their standards (NoM) its 127 +/- 10% so normal voltage range of 114V - 139V.
I found that pretty handy as you can run 240 motors and equipment on 220, granted many run fine on 208.
They do not appear to have a need for delta services like 240 hi-leg.
I did have access to a multimeter and was able to confirm the voltages.
The interesting thing is all the breakers and devices are the same as here '120V', I saw several Hubble GFCI's and the panels I saw were Square D, breakers are Square D QO 120/240, including GFCI breakers.
I would think that would be a little to high of a voltage for a US standard '120V' breaker or GFCI.
Anyways thought some of you would find that interesting.
Its based on the NEC and yeah yeah yeah its not always followed, but on big project's it is.
What I found interesting is in recent years the only two grid operators merged into one, and I don't know all the details but one used 220Y/127 and the other our 208Y/120 and they standardized on the 220Y/127 distribution.
They often serve customers from large three phase 220Y127 distribution transformers, customers are limited to a service of something like 60 Amps at single phase open wye (127/220), a small commercial building or even a farm that needs over 60 amps will often have this 220Y/127 three phase.
Many small residential customers in cities to villages still are on what appear to be 30A 127V two wire services.
Rural areas with only a line and neutral primary do have split phase 120/240 transformers.
I saw the nameplate of some equipment and it was in fact '127V' not the 120 or 115 or 117 I normally see here.
So I got interested and checked some more equipment and yeah most were '127'
I imagine in their standards (NoM) its 127 +/- 10% so normal voltage range of 114V - 139V.
I found that pretty handy as you can run 240 motors and equipment on 220, granted many run fine on 208.
They do not appear to have a need for delta services like 240 hi-leg.
I did have access to a multimeter and was able to confirm the voltages.
The interesting thing is all the breakers and devices are the same as here '120V', I saw several Hubble GFCI's and the panels I saw were Square D, breakers are Square D QO 120/240, including GFCI breakers.
I would think that would be a little to high of a voltage for a US standard '120V' breaker or GFCI.
Anyways thought some of you would find that interesting.
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