Barrier Block for Panel Wiring — 8 Circuits, 0.438" Pitch
The 387800308: Rated 15A per circuit, the limiting factor here is the screw terminal's contact area and the thermoplastic insulator's temperature rise, not the conductor itself. The top termination uses screws with a captive plate — that plate stays captured in the screw when you back it out, so you don't lose a washer down into the cabinet during a field rewire. The bottom termination is closed, meaning the screw terminal is the only access point; this block is a feed-through or internal junction, not a pass-through to another board layer.
The insulator is molded from thermoplastic rated UL94 V-0 — it won't sustain a flame inside an enclosed panel. Terminal screws are steel with a zinc, clear chromate finish; that's a standard industrial corrosion protection that holds up in dry indoor environments but isn't rated for outdoor or washdown duty. The housing is black, which is the default color for this series.
Sibling Comparison — 387800310 vs 387800306 vs 387800109
The 387800306 is a 6-circuit version, also with captive plates, but packed in tray rather than bulk. The 387800109 is a 9-circuit variant that uses standard screws without the captive plate — if you're doing high-volume production where dropped hardware isn't a concern, that saves a few cents per block, but for field service the captive plate is worth the premium.
Mounting and Wiring Notes
This block mounts to a chassis or panel via the flanges on each end — two screws through those flanges hold it in place. The dual-row layout gives 16 wire entries total (two per circuit), so you can daisy-chain or tap off each circuit without a separate jumper. Wire range is 14-22 AWG; strip length should follow the terminal manufacturer's recommendation for the screw size to get full contact pressure without damaging the strands.