Rockwell Automation 1715-OF8I Redundant I/O System User Manual - Manual (Page 93)

Rockwell Automation Publication 1715-UM001C-EN-P - March 2014 93
Installation Instructions Chapter 2
Field Loop Circuits for Digital Outputs
The field loop circuit for a digital output is shown in Figure 43 .
Figure 43 - Digital Output (simplex or duplex) Field Loop Circuit
IMPORTANT The field power 5A fuses comply with UL508 requirements. The 5A fuses are
No. 396/TE5 5A time lag fuse; UL 248-14, 125 V,T Leadfree; manufactured by
Littlefuse.
• You can use Class 2 power supplies for the +24V DC field voltage instead of
the two 5A fuses. Class 2 is defined by the NEC as providing less than 100
watts (at 24V).
• When digital output modules are configured as a redundant pair, the
minimum load current required for channels with line monitoring is 20 mA.
DC
DC
33002-M
Important: For inductive loads, a back EMF protection diode
is fitted at the load.