Reverse voltage protection
The Rail-UIO-IOTA power conditioning PWA (51307106-175) is mounted on the rail-mounted UIO
assembly, which is provided with the reverse protection feature. This feature protects the railmounted UIO modules from the reverse polarity.
8.6.2 Routing of DC power lines
Each rail-mounted UIO requires a separate pair of +24V DC and GND lines from the fused
Terminal Strip. The power lines are routed in the system tray of rail-mounted UIO. See Figure: DC
power line wiring through system tray in the section Wiring connections for illustration.
l Fused Terminal Block
l Circuit Breaker
8.6.3 Fused Terminal Block
The Terminal Block is fused and the typical fuse rating for powering a single rail-mounted UIO
module is as follows:
l Typical operating current: 15 Amps
l VDC: >30V
l Operating temperature: -40 to 70 degC
l Fast acting, Glass type removable fuse from the terminal block is preferred
l Meets the UL/CSA 248-14 standard
l I2t rating > 950 Amphere2 second
l Fuse should meet the local agency approval requirements
8.6.4 Circuit Breaker
The AC input line to the DC power system must be protected by an appropriately sized circuit
breaker.
Compliance
Power wiring must conform to the local electric code like NEC and CEC or any other local electric
code.
