Rockwell Automation SA500 DC Bus Supply - Manual (Page 19)

Installation Guidelines 3-5
3.5 DC Bus Supply Initial Installation
The following procedure is intended to be only a guide to assist you in installing the
DC bus supply. Refer to the wiring diagrams supplied with you system for more
specific information.
Step 1. Mount the DC bus supply. DC bus supplies are designed to be mounted on a
flat surface using M5 or #10 screws. The holes in the top flange are key-hole
shaped and the lower holes are U-shaped to facilitate mounting. The bus
supply should be mounted in a location with good air flow and in close
proximity to the SA500 AC Power Modules (3 mm (1/8 in) to 13 mm (1/2 in)
spacing between units). See figure 3.1. Provide at least 85 mm (3.3 in) of
clearance above and below the bus supply for ventilation.
Ambient air around the bus supply must be clean, dry, and free of flammable
or combustible vapors, chemical fumes, oil vapor, steam, and excessive
moisture and dirt.
The highest current AC Power Module should be placed closest to the bus
supply. Note that the SA500 AC Power Modules (6 maximum) should be
evenly distributed on each side of the bus supply. If two Power Modules are
being used, one should be wired from the left of the bus supply and one
should be wired from the right. If four Power Modules are being used, two
should be wired from the left of the bus supply and two from the right. If an
odd number of Power Modules is being used, they should be distributed as
evenly as possible on each side of the bus supply. This method of Power
Module placement minimizes wire length which reduces wire inductance.
The continuous DC bus current for all SA500 AC Power Modules connected
to the bus supply is limited to either 50A or 100A.