Understand system planning – Rockwell Automation 1797-PS1E FLEX Ex 85-253V AC In/Quad-Ex DC Out Power Supply User Manual

Page 4

Advertising
background image

4 FLEX Ex 85…253V ac In/Quad-Ex dc Out Power Supply

Publication

1797-5.33 - April 2007

The 1797-PS1E is an 85…253V ac in/quad-Ex dc out power supply in a
flame-proof enclosure with increased safety input/output terminations. The
85…253V ac gland is an M20 x 1,5 and can accept a cable from 6…12 mm
(0.267…0.472 in.) in diameter. The Ex outputs are M16 x 1,5 and can accept a
cable from 4…8 mm (0.157…0.315 in.) in diameter.
Features include the following:

• 85…253V ac supply source
• Four channels, 8.5 W output each channel
• Outputs are IS galvanically isolated from the source
• All channels are independently IS limited

Understand System Planning

Part of system planning is determining what modules are needed for the
application, how many power supplies are needed, how to best partition the
system, and where to locate the system cabinets.
A key task in the development cycle is determining the number of power
supply outputs (thus power supplies) you will need. In the following example,
you will need 11 power outputs if you are using the fiber hub, which requires
8.5 W.

Each power supply has four independent IS-power outputs capable of 8.5 W
each. In the above example, we required 11 IS-power outputs so 3 power
supplies were sufficient.

Modules

Requires

Modules

Requires

Fiber hub

8.5 W

Two thermocouple inputs

1.6 W each

Two ControlNet adapters

8.5 W each

Two digital outputs

7.5 W each

Two analog inputs

7.5 W each

Three NAMUR digital inputs

2.8 W each

Two analog outputs

6.3 W each

Two counter inputs

4.25 W each

Advertising