Figure 5-2 Jack Connector - Siemens SIMATIC S7-400H System Manual

Assembly of a CPU 41x–H
5.1 Operator controls and display elements of the CPUs
PROFINET interface
You can connect PROFINET IO devices to the PROFINET interface. The PROFINET
interface features two switched ports with external connectors (RJ 45). The PROFINET
interface provides the interconnection with Industrial Ethernet.
This interface only allows connection to an Ethernet LAN. You cannot connect it to the
public telecommunication network, for example.
You may only connect PROFINET-compliant network components to this interface.
Setting the rack number
Use the switch on the rear panel of the CPU to set the rack number. The switch has two
positions: 1 (up) and 0 (down). One CPU is allocated rack number 0, and the partner CPU is
assigned rack number 1. The default setting of all CPUs is rack number 0.
Connecting an external backup voltage to the "EXT. BATT." socket
The S7–400H power supply modules support the use of two backup batteries. This allows
you to implement the following:
● Back up the user program stored in RAM.
● Retain bit memories, timers, counters, system data and data in variable data blocks.
● Back up the internal clock.
You can achieve the same backup by connecting a DC voltage between 5 V DC and 15 V
DC to the "EXT. BATT." socket of the CPU.
Properties of the "EXT. BATT." input:
● Reverse polarity protection
● Short-circuit current limiting to 20 mA
For incoming supply at the "EXT. BATT" socket, you require a connecting cable with a 2.5
mm ∅ jack connector as shown in the figure below. Observe the polarity of the jack
connector.
Figure 5-2
50
CAUTION
Jack connector
System Manual, 03/2012, A5E00267695-11
S7-400H