Page 124 - Wago_AutomationTechnology_Volume3_2015_US.pdf

4 I/O-System — 750 and 753 Series
122 Application and Installation Instructions

Power supply
The fieldbus coupler always powers the internal
electronics’ power supply. The field-side power 24 V
supply is electrically isolated via the supply modu- Electronics
le on the fieldbus coupler or a separate potential
supply module. The division enables a separate
supply for sensors and actuators. Snapping I/O
modules together automatically routes the supply Fieldbus Coupler Supply Module Bus Module Supply Module End Module
voltages (system power supply 5 VDC via the with
data contacts and field supply via the optional
power jumper contacts). Supply modules with
diagnostics enable additional power supply moni-
toring. This ensures a flexible, user-specific supply
design for a station.
The current supply to the electronics is limited
by a maximum value. This value depends on the
fieldbus coupler used. If the sum of the internal
current demand of all the I/O modules exceeds
this value, an additional bus supply module is ne-
cessary. Even in this case, the power supply to the
field-side supply of 10 A may not be exceeded.
24 V 230 V 24 V
However, different power supply modules allow a Field potential 1 Field potential 2 Field potential 3
new power supply, formation of potential groups
and the implementation of emergency stops. Notes • For the 24 VDC power supply of electronics and
Additional steps must be must be implemented field, PELV/SELV power supply units are recom-
based on where the I/O-System is installed: mended. As part of a safety-related application,
• As part of shipbuilding or in the onshore/off- they are mandatory.
shore sector, specific power and field-side power • The mixed operation of safe and conventional
supply filters must be provided (750-624/626). modules streamlines system configuration. For
• As part of operating intrinsically safe Ex i mo- increased EMC immunity required according
dules, use of a specific supply module is required to the standard, WAGO offers compact filter
(750-625). In addition, specific power and modules for the power supply.
field-side power supply filters must be provided
Interference-free in safety-related applica- (750-624/626). Please refer to the manual for details about the
tions power supply’s design.
To safely and easily perform cost-effective, centra-
lized deactivation of complete actuator groups,
the actuator’s power supply can be switched off
using a safety switching device. This can either
be performed for each individual actuator or by
turning off the power supply to a group of control
outputs.
In the event of failure, ensure that no interference Supply module Output module
from other current or power circuits occurs — even Actuator 1
when the control voltage is switched off — so the
defined safety function properties (logic and time Safety switch module/ Actuator 2
response) remain unchanged. Safety module 1 5
D01 D02
Some modules are designed to provide interfe- 24 V
rence-free safety functionality. These modules voltage Safe
supply output 1 4 2 6
comply with safety requirements up to Category
0 V
4 of DIN EN ISO 13849-1:2007. The safety voltage
category and performance level depend solely supply 24 V 24 V
on the safety components and their wiring. Safe
Safety 2 5 3 7
components output
Attention!
Safe
Interference-free WAGO I/O modules have no input 0 V 0 V
active impact on the safety function — they are not Logic
an active part of the safety application and are Safe
input 3 6 4 8
not a substitute for the safety switching device!
When using the components in safety functions,
the corresponding notes must be observed in the
relevant manual.
Example: Two-channel, double-pole power supply disconnection