Alwayslearningelec
Senior Member
- Location
- NJ
- Occupation
- Estimator
Dumb question. Is the only difference between the two is that one is 1 pole and the other is 2 pole? Thanks.
125v vs 250v receptacle
- Thread starter Alwayslearningelec
- Start date
A 125v receptacle would be one phase conductor, 1 neutral conductor and most likely 1 equipment grounding conductor.
A 250v receptacle would be 2 phase conductors (or 3 for 3 phase), possibly but not necessarily a grounded conductor and likely a grounding conductor.
Look at a NEMA configuration chart.
A 250v receptacle would be 2 phase conductors (or 3 for 3 phase), possibly but not necessarily a grounded conductor and likely a grounding conductor.
Look at a NEMA configuration chart.
LarryFine
Master Electrician Electric Contractor Richmond VA
- Location
- Henrico County, VA
- Occupation
- Electrical Contractor
No, grounded contacts are poles just like ungrounded ones are.
The difference is slot shape, which is basically a rejection feature.
And, no, it's not a dumb question.
Alwayslearningelec
Senior Member
- Location
- NJ
- Occupation
- Estimator
Well Augie says (2) ungrounded conductors isn't that 2 poles?
LarryFine
Master Electrician Electric Contractor Richmond VA
- Location
- Henrico County, VA
- Occupation
- Electrical Contractor
120v is 2-pole, 240v is 2-pole, 120/240v is 3-pole, etc.
Receptacle poles are not the same as breaker poles.
It's not the quantity of hot wires, it's the quantity of circuit wires.
Receptacle poles are not the same as breaker poles.
It's not the quantity of hot wires, it's the quantity of circuit wires.
Last edited:
winnie
Senior Member
- Location
- Springfield, MA, USA
- Occupation
- Electric motor research
Receptacles have several different ratings.
Poles and wires tell you the number of circuit contacts and the number of total contacts respectively. A 2 pole 3 wire receptacle has two circuit contacts but 3 total contacts, implying an EGC contact.
Then you have the configuration voltage rating. This is the voltage, current, and system associated with the shape of the receptacle and contacts. The idea is to maintain non-interchangability, so you can't plug your 120V device into a 240V receptacle.
Finally you have the actual voltage and current ratings of the receptacle. In many cases all of a manufacturers receptacles will have te same insulation ratings, such as 480V or 600V, even for lower voltage configurations. It can be difficult to find this documented, usually just a catalog line saying 'all devices are built to a voltage rating of....'
Jon
Poles and wires tell you the number of circuit contacts and the number of total contacts respectively. A 2 pole 3 wire receptacle has two circuit contacts but 3 total contacts, implying an EGC contact.
Then you have the configuration voltage rating. This is the voltage, current, and system associated with the shape of the receptacle and contacts. The idea is to maintain non-interchangability, so you can't plug your 120V device into a 240V receptacle.
Finally you have the actual voltage and current ratings of the receptacle. In many cases all of a manufacturers receptacles will have te same insulation ratings, such as 480V or 600V, even for lower voltage configurations. It can be difficult to find this documented, usually just a catalog line saying 'all devices are built to a voltage rating of....'
Jon
