# Enphase max current

#### ggunn

##### PE (Electrical), NABCEP certified
The Enphase spec sheet doesn't list a max current, only a nominal current. When figuring conductor sizes for an Enphase system, should I add the extra 25% to the current for excess insolation or not? My guess is no.

#### GoldDigger

##### Moderator
Staff member
IMHO for a microinverter or a string inverter the key number is the nominal output power or current. (Unlike the DC side where you multiply the panel current by 1.25 to allow for excess insolation).
You multiply the nominal output by 1.25 for continuous operation and that is it.
Now if the micro is rated for, say 280W, that will be a different output current if you use it on a 208V system or a 240V system.

#### Zee

##### Senior Member
IMHO for a microinverter or a string inverter the key number is the nominal output power or current. (Unlike the DC side where you multiply the panel current by 1.25 to allow for excess insolation).
You multiply the nominal output by 1.25 for continuous operation and that is it.
Now if the micro is rated for, say 280W, that will be a different output current if you use it on a 208V system or a 240V system.
I would agree.

Per NEC logic:
Enphase is an "inverter output circuit" not a "dc source circuit". So no 125% PV use factor..... AKA..... insolation factor applies.
Just the 125% continuous.

Per real world logic:
any edge of cloud effect, super cold Temps, snow reflectance, etc. can drive a PV panel above its nominal rating. Not an inverter.

#### jaggedben

##### Senior Member
I don't know why they say nominal instead of maximum. I think it's just a mistake.