Allen-Bradley FLEX Ex 1797-PS2E2 User manual

Publication 1797-IN535F-EN-P - August 2017
Installation Instructions
FLEX Ex Power Supply
Catalog Number 1797-PS2E2
Topic Page
Important User Information 2
About the Power Supply 3
Understand System Planning 4
Installation in Zone 1, 22 6
Electrostatic Charge 8
Outputs 9
Mount the 1797-PS2E2 Power Supply 10
Customer Connections 11
Typical Wiring Configurations 11
Mounting Dimensions and Terminal Base Assignments for the
1797-PS2E2 Power Supply
12
Repair 12
FLEX Ex Power Supply, cat. no. 1797-PS2E2 13
Ferrite Beads 15

2FLEX Ex Power Supply
Publication 1797-IN535F-EN-P - August 2017
Important User Information
Solid state equipment has operational characteristics differing from those of electromechanical
equipment. Safety Guidelines for the Application, Installation and Maintenance of Solid State Controls
(Publication SGI-1.1 available from your local Rockwell Automation sales office or online at
http://literature.rockwellautomation.com) describes some important differences between solid state
equipment and hard-wired electromechanical devices. Because of this difference, and also because of the
wide variety of uses for solid state equipment, all persons responsible for applying this equipment must
satisfy themselves that each intended application of this equipment is acceptable.
In no event will Rockwell Automation, Inc. be responsible or liable for indirect or consequential damages
resulting from the use or application of this equipment.
The examples and diagrams in this manual are included solely for illustrative purposes. Because of the
many variables and requirements associated with any particular installation, Rockwell Automation, Inc.
cannot assume responsibility or liability for actual use based on the examples and diagrams.
No patent liability is assumed by Rockwell Automation, Inc. with respect to use of information, circuits,
equipment, or software described in this manual.
Reproduction of the contents of this manual, in whole or in part, without written permission of Rockwell
Automation, Inc., is prohibited.
Throughout this manual we use notes to make you aware of safety considerations.
WARNING
Identifies information about practices or circumstances that can cause an explosion in a
hazardous environment, which may lead to personal injury or death, property damage, or
economic loss.
IMPORTANT
Identifies information that is critical for successful application and understanding of the
product.
ATTENTION
Identifies information about practices or circumstances that can lead to personal injury or
death, property damage, or economic loss. Attentions help you identify a hazard, avoid a
hazard, and recognize the consequence
SHOCK HAZARD
Labels may be on or inside the equipment to alert people that dangerous voltage may be
present.
BURN HAZARD
Labels may be on or inside the equipment to alert people that surfaces may be dangerous
temperatures.

FLEX Ex Power Supply 3
Publication 1797-IN535F-EN-P - August 2017
About the Power Supply
The power supply is an essential component in the operation of an
intrinsically safe system. It must isolate the unsafe incoming power from the
control system and limit the available energy to IS-safe levels.
No other power sources are needed to operate any components attached to
the FLEX Ex system in the hazardous area. Power for valves, actuators, or
transmitters come from the FLEX Ex modules.
ATTENTION
This equipment is considered Group 1, Class A industrial equipment
according to IEC/CISPR Publication 11. Without appropriate
precautions, there may be potential difficulties ensuring
electromagnetic compatibility in other environments due to
conducted as well as radiated disturbance.
This equipment is supplied as enclosed equipment. It should not
require additional system enclosure when used in locations
consistent with the enclosure type ratings stated in the
Specifications section of this publication. Subsequent sections of
this publication may contain additional information regarding
specific enclosure type ratings, beyond what this product provides,
that are required to comply with certain product safety certifications.
1797-PS2E2
30686

4FLEX Ex Power Supply
Publication 1797-IN535F-EN-P - August 2017
The 1797-PS2E2 is a 24V dc in/quad-Ex dc out power supply in an
flame-proof enclosure with increased safety input and output terminations.
The 24V dc 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:
•24V dc supply source
•Four channels, 8.5 W output each channel
•Dual power feeds for source input redundancy
•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

FLEX Ex Power Supply 5
Publication 1797-IN535F-EN-P - August 2017
The total number of power supplies needed depends on the modules used
and the total system configuration. The following illustration shows how this
example may be configured.
IMPORTANT
Even though modules may be supplied with power from the same
power-supply output channel, galvanic isolation in the module
provides module-to-module galvanic isolation. Depending upon
the module-type, galvanic isolation (channel-to-channel within the
module) may or may not be provided. See the module’s
specifications for more information.
IS Pwr
Safe Area
Hazardous Area
1797 power supply
1797 power supply
1797 power supply
ACNR Spare IE8 OE8 IRT8 Spare Spare IJ2 IJ2
ACNR OB4 OB4D IBN16 IBN16 IBN16 IE8 IRT8 OE8
RPA RPFM RPFM
IS 1797 I/O
IS 1797 I/O
IS 1797 Fiber Hub
IS Pwr
IS Pwr
IS Pwr
IS Pwr
IS Pwr
IS Pwr
IS Pwr
IS Pwr
IS Pwr
IS Pwr
IS Pwr
Ex d/e
Ex ib
Ex d/e
Ex ib
Ex d/e
Ex ib
41306
Unsafe
Power
Entrance
Spare
Unsafe
Power
Entrance
Unsafe
Power
Entrance

6FLEX Ex Power Supply
Publication 1797-IN535F-EN-P - August 2017
Make certain that you only connect intrinsically-safe power supplies to other
intrinsically-safe system modules or adapters to maintain the integrity of the
intrinsically-safe backplane.
Installation in Zone 1, 22
The 1797-PS2E2 power supply has a protection factor of IP65. Refer to the
specifications table for the IS module type.
Application
When installing, commissioning, operating, and maintaining devices or device
components of the FLEX Ex system as intrinsically-safe electrical apparatus
in potentially explosive atmospheres according to EN 60079-11, you must
heed the EC- type examination certificate and the applicable national and
local construction, installation, and operating regulations.
Zone 1
The power supply can be located in Zone 1. The permissible ambient
temperature of -20…70 °C must not be exceeded.
Zone 22
The housing type of the power supply is applicable for use in Zone 22. It
corresponds with the category 3D acc. to directive 94/9 EC and is marked
with a type label accordingly.
WARNING
The power supply cannot be used in an intrinsically safe environment
after its outputs have been exposed to nonintrinsically safe signals.
41307

FLEX Ex Power Supply 7
Publication 1797-IN535F-EN-P - August 2017
Installation and Commissioning
The power supply unit can be located in Zones 1, 2, and 22 as stated on its
label. The output circuits are according to the ignition protection class Ex ib
and can be installed in Zones 1, 2, and 22. When installing, you must heed the
EC- type examination certificate (especially the special conditions) and the
applicable national and local construction, installation, and operating
regulations.
The housing (Ex d) must not be opened (screw cover). Connections are made
in the (Ex e) terminal box.
Install the power feed lines only in the deenergized state. Also follow the
information on the type label, respectively the covers of the terminals.
You can connect and disconnect the intrinsically-safe output terminals during
operation.
All unused cable glands must be covered by appropriate prototype tested Ex e
lead seals to keep the requirement of IP54.
The cover installed on the nonintrinsically-safe screw terminals
(IP30) may be removed only in the deenergized state and must be remounted
after working on these terminals.
Before closing the cover of the (Ex e) wiring box, inspect the seal for any
signs of damage. In case of damage, the seal must be replaced by a new seal
that is identical to the damaged seal.
The power supply housing contains two flanges, which can be connected to a
wall or other structural part by means of fixing screws. Select fixing screws
that ensure secure fixing of the power supply. Consider the condition of
vibration of the power supply when making this selection.
On the (Ex d) housing there is an earthing screw. This screw must be
connected to Earth with a conductor having a minimum of 4 mm² (0.006 in.2)
area. The connection has to be protected against self-opening and corrosion.
Corrosion protection can be achieved by using tinned terminal ends.
Before opening the (Ex e) terminal box (for example, for maintenance
purposes), it must be cleaned of all dust particles to ensure that no dust can
enter the box.

8FLEX Ex Power Supply
Publication 1797-IN535F-EN-P - August 2017
Electrostatic Charge
Protect the system against electrostatic charge. Post a sign near this module.
WARNING Avoid electrostatic charging.
ADVERTÊNCIA! PREVENIR CONTRA O ACÚMULO DE CARGA
ELETROSTÁTICA.
For your convenience, a sign that can be cut out and posted is included on the
last page of these installation instructions.
European Hazardous Location Approval
The following applies to products marked II 2 G
•Are Equipment Group II, Equipment Category 2, and comply with
the Essential Health and Safety Requirements relating to the design
and construction of such equipment given in Annex II to Directive
2014/34/EU. See the EC Declaration of Conformity at
http://www.rockwellautomation.com/products/certification
for details.
•The type of protection is “Ex de [ib] IIC T4 Gb” according
to EN 60079-11.
•Comply to Standards EN 60079-0:2012, EN 60079-1:2007,
EN 60079-7:2007, and EN 60079-11:2012, reference certificate
number DMT 02 ATEX E 253 X.
•Are intended for use in areas in which explosive atmospheres caused
by gases, vapors, mists, or air are likely to occur occasionally. Such
locations correspond to Zone 1 or 2 classification according to ATEX
directive 2014/34/EU.

FLEX Ex Power Supply 9
Publication 1797-IN535F-EN-P - August 2017
IEC Hazardous Location
The following applies to products with the IECEx certification:
•Are intended for use in areas in which explosive atmospheres caused
by gases, vapors, mists, or air are likely to occur only infrequently and
for short periods. Such locations correspond to Zone 1 or 2
classification to IEC 60079-0.
•The type of protection is “Ex de [ib] IIC T4 Gb” according to
IEC 60079-11.
•Comply to Standards IEC 60079-0:2011, IEC 60079-1:2007-04,
IEC 60079-7:2006-07, and IEC 60079-11:2011, reference IECEx
certificate number IECEx BVS 09.0019X.
Special Conditions for Safe Use:
For an ambient temperature above 60 °C, power supplies must be connected
with leads that are designed for a service temperature of at least 80 °C.
Outputs
When using an intrinsically-safe electrical apparatus according to EN
60079-11, the European directives and regulations must be followed.
The channels in the power supply are electrically connected to each other and
have a common +V line.
IMPORTANT
You cannot interconnect lines because of the intrinsic safety
requirements.

10 FLEX Ex Power Supply
Publication 1797-IN535F-EN-P - August 2017
Mount the 1797-PS2E2 Power Supply
Follow these directions to properly install the 1797-PS2E2 power supply.
Refer to the Installation and Commissioning section, page 7, for important
precautions and considerations.
1. Remove the screws on the cover of the power supply Ex e terminal
box to access the input and output terminals.
2. Thread the blue IS-safe output power wiring through the blue IS
compression seals.
3. Connect the blue IS-safe output power wiring to the output terminals
making sure all connections are tight.
These power supply outputs provide the input power to the FLEX Ex
modules.
4. Thread the hazardous incoming-power wiring through the black
compression seals.
5. Connect the hazardous incoming-power wiring to the input terminals
making sure all connections are tight.
You can daisy-chain the hazardous incoming-power wiring to further
supplies to simplify system wiring.
ATTENTION
Use star washers and nuts to make sure you have a good electrical
connection. Scrape the paint off the back panel in those areas where
grounding bolts will be located.
ATTENTION
Keep hazardous and IS-safe wiring separated in a suitable
fashion. Do not leave long, excess wiring that could bridge
between the hazardous and safe areas.