Allen-Bradley 1771-P7B SLC 500 PLC Power Supply

The Allen-Bradley 1771-P7B is a stand-alone AC-to-DC power supply for a single 1771 I/O chassis in PLC-5/SLC 500 systems, designed to power 1771-A1B, -A2B, -A3B, -A3B1, or -A4B I/O modules when used with an adapter module or a PLC-5 processor that does not include an internal power supply. It accepts 120/220 VAC input (nominal), with voltage ranges of 97–132 V and 195–264 V and a frequency of 47–63 Hz, drawing about 2.0 A at 120 V (1.0 A at 220 V) and delivering real input power of 108 W (176 VA). The supply provides a regulated 5.06 V DC output capable of up to 16 A, with a typical output tolerance of ±3.8%, suitable for energizing an entire 1771 I/O chassis. Physical and electrical specs include a fuse rated at 3 A, 250 V (3AG), and isolation ratings of 2500 V DC for 1 s and 1800 V AC (rms) for 1 s for safety between the input and output, with cabling options 1771-CP1 Local, 1771-CP2 Remote 5 ft, and 1771-CP3 Remote 5 ft. The unit measures about 4.5 in x 12.4 in x 6.3 in (115 mm x 317 mm x 160 mm) and is intended for industrial environments where an external 5 V supply is required to power a PLC-5/SLC 500 I/O rack that lacks its own internal power source.