wire size
- Thread starter relbas
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qcroanoke
Sometimes I don't know if I'm the boxer or the bag
- Location
- Roanoke, VA.
- Occupation
- Sorta retired........
Wire is #8.
I would probably put it on a 45 amp breaker but I'm not that good at sizing protection.
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
If it is a continuous load you must use 125% of the load for minimum conductor size as well as overcurrent protection.
So if not a continuous load your conductor must be rated at least 38 amps - and a 40 amp overcurrent device would meet code.
If a continuous load then the conductor must be rated at least 47.5 amps and you would need a 50 amp overcurrent device.
8 AWG 75 deg conductor is needed in either case, but you could need 6 AWG if you have to use 60 deg ampacity or if any other adjustments are necessary.
So if not a continuous load your conductor must be rated at least 38 amps - and a 40 amp overcurrent device would meet code.
If a continuous load then the conductor must be rated at least 47.5 amps and you would need a 50 amp overcurrent device.
8 AWG 75 deg conductor is needed in either case, but you could need 6 AWG if you have to use 60 deg ampacity or if any other adjustments are necessary.
- Location
- Massachusetts
Plot twist, the appliance is 400' from the panel.
qcroanoke
Sometimes I don't know if I'm the boxer or the bag
- Location
- Roanoke, VA.
- Occupation
- Sorta retired........
#2 per "Voltage Drop Calculator" by Nick Debaggis
my quetion is do I have to calculate the 125% or it is calculated by the manufactire?
my quetion is do I have to calculate the 125% or it is calculated by the manufactire?
my question is: do I have to calculate the 125% or it is calculated by the manufacture and it is included with the name plate data?
my quetion is do I have to calculate the 125% or it is calculated by the manufactire?
my question is: do I have to calculate the 125% or it is calculated by the manufacture and it is included with the name plate data?
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qcroanoke
Sometimes I don't know if I'm the boxer or the bag
- Location
- Roanoke, VA.
- Occupation
- Sorta retired........
The nameplate rating is what it pulls.
It does not include the 125% that is HVAC and motor name plates.
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
The 125% for continuous will not be included in the nameplate current listing.
If an appliance lists a minimum circuit ampacity instead, I would expect that to take into consideration the 125%. But keep in mind that "continuous" adjustments for branches and feeders generally do not apply to motor loads.
Also for a single load on a branch breaker you may need to consider the 80% of rating rule.
Tapatalk!
If an appliance lists a minimum circuit ampacity instead, I would expect that to take into consideration the 125%. But keep in mind that "continuous" adjustments for branches and feeders generally do not apply to motor loads.
Also for a single load on a branch breaker you may need to consider the 80% of rating rule.
Tapatalk!
- Location
- New Jersey
- Occupation
- Journeyman Electrician
J.P.
Senior Member
- Location
- United States
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
Don't confuse anyone here into thinking a "double adjustment" is needed.
If we take the OP unit with a rating of 38 amps and multiply by 125% we get 47.5. That is the minimum ampacity of conductor needed. At same time if we use that same figure as a base for minimum overcurrent protection we will also meet the 80% loading rule of the device. 38 amps is less then 80% of a 50 amp breaker in this case.
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