Hey all, I'm wondering if downsizing neutrals as per 705.95(B) would apply to neutrals on the supply side of the PV disconnect. 705.95(B) refers to sizing the neutral to the *EGC*, but since there is no EGC on the supply side of the PV Disconnect I'm unclear if it we could utilize that code section for anything on the supply side. I can find quite a few conversations about applying 705.95(B) on the loadside, but I'm not finding anything specific to tap conductors. Thoughts?
705.95(B) and tap conductors
- Thread starter am1954
- Start date
Greentagger
Senior Member
- Location
- Texas
- Occupation
- Master Electrician, Electrical Inspector
Are you looking for 705.11(B)?
jaggedben
Senior Member
- Location
- Northern California
- Occupation
- Solar and Energy Storage Installer
@am1954
Referencing 705.95(B) means you must be on the 2017 code.
Your description sounds like a supply side connection ("no egc"), so I'm going to assume that your use of "tap conductors" in the topic subject line is mistaken and does not apply. ("Tap conductors" normally refers to load side conductors covered in 240.21(B).
For the neutral on the supply side of a supply side connected PV system: No, 705.95(B) cannot be applied. As a practical matter, the neutral is a fault carrying conductor and cannot be too undersized for that purpose. As far as code, see 250.24(C), which requires your neutral to be size no smaller than required in table 250.102(C)(1).
You may still be able to size the neutral smaller than the ungrounded conductors per 250.102(C)(1), but the requirement on the supply side of the disconnect may be larger than 705.95(B) allows on the PV side of the disconnect.
Referencing 705.95(B) means you must be on the 2017 code.
Your description sounds like a supply side connection ("no egc"), so I'm going to assume that your use of "tap conductors" in the topic subject line is mistaken and does not apply. ("Tap conductors" normally refers to load side conductors covered in 240.21(B).
For the neutral on the supply side of a supply side connected PV system: No, 705.95(B) cannot be applied. As a practical matter, the neutral is a fault carrying conductor and cannot be too undersized for that purpose. As far as code, see 250.24(C), which requires your neutral to be size no smaller than required in table 250.102(C)(1).
You may still be able to size the neutral smaller than the ungrounded conductors per 250.102(C)(1), but the requirement on the supply side of the disconnect may be larger than 705.95(B) allows on the PV side of the disconnect.