What It Is and Key Ratings
The Siemens 6ES7405-0KR02-0AA0 is a SIMATIC S7-400 power supply (PS405) that takes a wide-range 24/48/60 V DC input and delivers 5 V DC at up to 10 A to the backplane bus, with no base load required. It is designed for redundant use, occupies 2 slots, and carries BIS, CCC, and FM approvals (Ta 0°C to 60°C T4).
The 5 V DC / 10 A backplane current is the critical figure. It determines how many S7-400 modules you can hang off this supply without a second unit. Because no base load is required, you don't need to waste current on dummy loads when the rack is lightly populated. The 24/48/60 V DC input flexibility means it works with common industrial battery and rectifier systems; just derate the input current as the voltage drops. The 2-slot footprint is non-negotiable for rack planning. If your chassis is tight on space, remember this supply takes two adjacent slots — typically in the leftmost positions. The 20 W typical power loss means you'll need some ventilation, but that's standard for a 10 A supply in this class. FM approval T4 (Ta 0°C to 60°C) means it's rated for use in ordinary locations with flammable gases present — useful if the panel sits in a classified area. Combined with BIS and CCC, it covers most global project requirements without extra certification lead time.