||All meter bases listed in this table are "ringless" style and are rated 600 volts AC unless otherwise noted.
||All polyphase socket style bases must contain a lever bypass rated 100% continuous duty.
||The manufacturer's catalog number must be stamped on the outside of the meter base so that it will be visible after the base is installed. The number must not be stamped on the cover.
||When aluminum conductors are used, the electrical contractor must apply the corrosion inhibiting compound recommended by and in the manner prescribed by the cable manufacturer.
||All 200 amp meter bases capable of accepting 500 Kcmil conductor must be marked "200 Amp Capacity".
||The third jaw from the left (as viewed from the front) on the bottom row of the seven jaw block must be connected to the neutral using a #14 awg or larger copper wire.
- 200 Amp Service - The conduit KO directly under the line (utility) terminals must accept a 3 inch conduit.
- 400 Amp (Cl 320) Service - The conduit KO directly under the line (utility) terminals must accept a 4 inch conduit. The conduit KOs directly under the load terminals must accept two(2) 3 1/2 inch conduits.
Class 320 Meter Bases:
- All 320 amp meter bases contain stud terminals.
- Only UL approved lay-in or box style connectors suitable for use with copper or aluminum conductors can be installed for wire termination on the studs.
- Compression connectors are not permitted.
- The upper right hand jaw (as viewed from the front) must contain an "anti-inversion" insert to prevent inverted meter installation or installation of a lower class meter.