Endress+Hauser RN22 User manual

Products Solutions Services
Operating Instructions
RN22
1- or 2-channel active barrier for safe separation of 4 to
20 mA standard signal circuits, optionally available as a
signal doubler. HART-transparent
BA02004K/09/EN/01.20
71528972
2020-12-14

Table of contents RN22
2 Endress+Hauser
Table of contents
1 About this document ................ 3
1.1 Document function ..................... 3
1.2 Symbols .............................. 3
1.3 Registered trademarks ................... 4
2 Basic safety instructions ............ 5
2.1 Requirements for the personnel ............ 5
2.2 Designated use ........................ 5
2.3 Workplace safety ....................... 5
2.4 Operational safety ...................... 5
2.5 Product safety ......................... 6
2.6 Installation instructions .................. 6
3 Product descriptions ................ 7
3.1 Product description RN22 ................. 7
4 Incoming acceptance and product
identification ....................... 7
4.1 Incoming acceptance .................... 7
4.2 Product identification .................... 8
4.3 Scope of delivery ....................... 9
4.4 Certificates and approvals ................ 9
4.5 Storage and transport ................... 9
5 Installation ........................ 9
5.1 Installation conditions ................... 9
5.2 Installing the DIN rail bus connector ........ 10
5.3 Installing a DIN rail device ............... 10
5.4 Disassembling the DIN rail device .......... 11
6 Electrical connection .............. 11
6.1 Connection conditions .................. 11
6.2 Quick wiring guide ..................... 12
6.3 Connecting the supply voltage ............ 12
6.4 Post-connection check .................. 13
7 Operation options ................. 14
7.1 Display and operating elements ........... 14
8 Commissioning .................... 14
8.1 Post-installation check .................. 14
8.2 Switching on the device ................. 14
9 Diagnostics and troubleshooting ... 15
9.1 General troubleshooting ................. 15
10 Maintenance ...................... 15
11 Repair ............................ 15
11.1 General information ................... 15
11.2 Spare parts .......................... 16
11.3 Return .............................. 16
11.4 Disposal ............................ 16
12 Technical data .................... 16
12.1 Function and system design .............. 16
12.2 Input ............................... 17
12.3 Output ............................. 17
12.4 Power supply ......................... 18
12.5 Performance characteristics .............. 20
12.6 Installation .......................... 20
12.7 Environment ......................... 21
12.8 Mechanical construction ................ 22
12.9 Display and operating elements ........... 23
12.10 Ordering information ................... 23
12.11 Accessories .......................... 24
12.12 Certificates and approvals ............... 24
12.13 Supplementary documentation ............ 25
13 Appendix: system overview of RN
Series ............................ 26
13.1 Power supply of RN Series ............... 26
13.2 Applications of the RN Series devices ....... 32
Index .................................. 39

RN22 About this document
Endress+Hauser 3
1 About this document
1.1 Document function
These Operating Instructions contain all the information that is required in various phases
of the life cycle of the device: from product identification, incoming acceptance and
storage, to mounting, connection, operation and commissioning through to
troubleshooting, maintenance and disposal.
1.2 Symbols
1.2.1 Safety symbols
DANGER
This symbol alerts you to a dangerous situation.
Failure to avoid this situation will result in serious or
fatal injury.
WARNING
This symbol alerts you to a dangerous situation.
Failure to avoid this situation can result in serious or
fatal injury.
CAUTION
This symbol alerts you to a dangerous situation.
Failure to avoid this situation can result in minor or
medium injury.
NOTICE
This symbol contains information on procedures and
other facts which do not result in personal injury.
1.2.2 Symbols for certain types of information
Symbol Meaning
Permitted
Procedures, processes or actions that are permitted.
Preferred
Procedures, processes or actions that are preferred.
Forbidden
Procedures, processes or actions that are forbidden.
Tip
Indicates additional information.
Reference to documentation
A
Reference to page
Reference to graphic
Notice or individual step to be observed
1.
,
2.
,
3.
… Series of steps
Result of a step
Help in the event of a problem
Visual inspection

About this document RN22
4 Endress+Hauser
1.2.3 Electrical symbols
Direct current Alternating current
Direct current and alternating current Ground connection
A grounded terminal which, as far as
the operator is concerned, is
grounded via a grounding system.
1.2.4 Symbols in graphics
1, 2, 3,... Item numbers A, B, C, ... Views
1.2.5 Symbols at the device
Warning
Observe the safety instructions contained in the associated Operating Instructions
1.3 Registered trademarks
HART®
Registered trademark of the FieldComm Group, Austin, Texas, USA

RN22 Basic safety instructions
Endress+Hauser 5
2 Basic safety instructions
2.1 Requirements for the personnel
The personnel for installation, commissioning, diagnostics and maintenance must fulfill
the following requirements:
‣Trained, qualified specialists must have a relevant qualification for this specific function
and task.
‣Are authorized by the plant owner/operator.
‣Are familiar with federal/national regulations.
‣Before starting work, read and understand the instructions in the manual and
supplementary documentation as well as the certificates (depending on the
application).
‣Follow instructions and comply with basic conditions.
The operating personnel must fulfill the following requirements:
‣Are instructed and authorized according to the requirements of the task by the facility's
owner-operator.
‣Follow the instructions in this manual.
2.2 Designated use
2.2.1 Active barrier
The active barrier is used for the safe isolation of 0/4 to 20 mA standard signal circuits.
An intrinsically safe version is optionally available for operation in Zone 2. The device is
designed for installation on DIN rails in accordance with IEC 60715.
A use in a manner not specified by the manufacturer’s manual may impair the safety.
2.2.2 Product liability
The manufacturer does not accept any responsibility for damage that results from non-
designated use and from failure to comply with the instructions in this manual.
2.3 Workplace safety
For work on and with the device:
‣Wear the required personal protective equipment according to federal/national
regulations.
2.4 Operational safety
Risk of injury!
‣Operate the device only if it is in proper technical condition, free from errors and faults.
‣The operator is responsible for interference-free operation of the device.
Modifications to the device
Unauthorized modifications to the device are not permitted and can lead to unforeseeable
dangers:
‣If modifications are nevertheless required, consult with the manufacturer.
Repair
To ensure continued operational safety and reliability:
‣Carry out repairs on the device only if they are expressly permitted.

Basic safety instructions RN22
6 Endress+Hauser
‣Observe federal/national regulations pertaining to the repair of an electrical device.
‣Use only original spare parts and accessories from the manufacturer.
Hazardous area
To eliminate danger to persons or the facility when the device is used in the hazardous
area (e.g. explosion protection):
‣Check the nameplate to verify if the device ordered can be put to its intended use in the
hazardous area.
‣Observe the specifications in the separate supplementary documentation that is an
integral part of these instructions.
2.5 Product safety
This device is designed in accordance with good engineering practice to meet state-of-the-
art safety requirements, has been tested, and left the factory in a condition in which it is
safe to operate.
2.6 Installation instructions
• The device's IP20 degree of protection is intended for a clean and dry environment.
• Do not expose the device to mechanical and/or thermal stress that exceeds the specified
limits.
• The device is intended for installation in a cabinet or similar housing. The device may
only be operated as an installed device.
• To protect against mechanical or electrical damage, the device must be installed in an
appropriate housing with a suitable degree of protection according to IEC/EN 60529.
• The device fulfills the EMC regulations for the industrial sector.
• NE 21: Electromagnetic compatibility (EMC) of industrial process and laboratory control
equipment is met under the following condition: power failures of up to 20 ms must be
bridged with a suitable power supply.
LCAUTION
‣The device may only be powered by a power unit with an energy-limited circuit in
accordance with UL/EN/IEC 61010-1, Section 9.4 and the requirements of Table 18.

RN22 Product descriptions
Endress+Hauser 7
3 Product descriptions
3.1 Product description RN22
3.1.1 Product design
Active barrier, 1-channel
• The active barrier is used for the transmission and galvanic isolation of 0/4 to 20 mA
signals. The device has an active/passive current input to which a 2- or 4-wire
transmitter can be directly connected. The output of the device can be operated actively
or passively. The current signal is then available to the PLC / controller or to other
instrumentation at plug-in screw terminals or optional push-in terminals.
• HART communication signals are transmitted bidirectionally by the device. Connecting
points for connecting HART communicators are integrated into the front of the device.
• The device is optionally available as an "associated apparatus", which allows devices to be
connected in Ex Zone 0/20 [ia] and operated in Ex Zone 2 [ec]. 2-wire transmitters are
supplied with power, and transmit analog 0/4 to 20 mA measured values from the
hazardous area to the non-hazardous area. These devices are accompanied by separate
Ex documentation, which is an integral part of this manual. Compliance with the
installation instructions and connection data in this documentation is mandatory!
Active barrier, 2-channel
With the "2-channel" option, the device has a second channel, which is galvanically isolated
from channel 1, while maintaining the same width. Otherwise, the function corresponds to
the 1-channel device.
Active barrier as signal doubler
With the signal doubler option, the active barrier is used for the galvanic isolation of a
0/4 to 20 mA signal, which is transmitted to two galvanically isolated outputs.
• Output 1 is HART-transparent. HART communication signals are transmitted
bidirectionally between the input and output 1.
• As output 2 contains a HART filter, only the galvanically isolated analog 4 to 20 mA
signal is transmitted.
4 Incoming acceptance and product
identification
4.1 Incoming acceptance
Check the following during incoming acceptance:
• Are the order codes on the delivery note and the product sticker identical?
• Are the goods undamaged?
• Do the nameplate data match the ordering information on the delivery note?
If one of these conditions is not met, please contact the manufacturer's sales office.

Incoming acceptance and product identification RN22
8 Endress+Hauser
4.2 Product identification
The following options are available for identification of the device:
• Nameplate specifications
• Extended order code with breakdown of the device features on the delivery note
• Enter the serial number from the nameplate in the W@M Device Viewer
(www.endress.com/deviceviewer): all data relating to the device and an overview of the
Technical Documentation supplied with the device are displayed.
• Enter the serial number on the nameplate into the Endress+Hauser Operations App or
scan the 2-D matrix code (QR code) on the nameplate with the Endress+Hauser
Operations App: all the information about the device and the technical documentation
pertaining to the device is displayed.
4.2.1 Nameplate
The right device?
Compare and check the data on the nameplate of the device against the requirements of
the measuring point:
6
0044
iTEMP®TMT82
Made in Germany 2012 D-87484 Nesselwang
TAGXXXXXXXXXXX
TAGXXXXXXXXXXX
Order code: TMT82-xxx/xx
Ext. ord. cd.: XXXXXXXXXXX
Ser. no.: XXXXXXXXX
Input: 12-42 V
Current cunsum.: 23,0 mA
1
EH 08.001X
II3G Ex nA II T6/T5/T4 Ta= -40 ...+ 55/70/85°C
II3G Ex nL IIC T6/T5/T4 Ta= -40 ... +55/70/85°C
Install per XA0xxxxT/09/a3/xx.xx
7
1
2
3
4
5
7
8
A0041996
 1 Nameplate (example of Ex version)
1 Product name and manufacturer ID
2 Order code, extended order code and serial number, DataMatrix 2D code, FCC-ID (if applicable)
3 Power supply and current consumption, output
4 Approval in hazardous area with number of the relevant Ex documentation (XA...)
5 Fieldbus communication logo
6 Firmware version and device revision
7 Approval logos
8 2 lines for the TAG name
4.2.2 Name and address of manufacturer
Name of manufacturer: Endress+Hauser Wetzer GmbH + Co. KG
Address of manufacturer: Obere Wank 1, D-87484 Nesselwang
Model/type reference: RN22

RN22 Installation
Endress+Hauser 9
4.3 Scope of delivery
The scope of delivery comprises:
• Device as per order
• Printed copy of the Brief Operating Instructions
• Optional: Functional safety manual (SIL mode)
• Additional documentation for devices which are suitable for use in the hazardous area
(0 1), such as Safety Instructions (XA...), Control or Installation Drawings (ZD...).
4.4 Certificates and approvals
For certificates and approvals valid for the device: see the data on the nameplate
Approval-related data and documents: www.endress.com/deviceviewer → (enter the
serial number)
4.4.1 Functional safety
A SIL version of the device is optionally available. It can be used in safety equipment in
accordance with IEC 61508 up to SIL 2 (SC 3).
Please refer to Safety Manual FY01034K for the use of the device in safety
instrumented systems according to IEC 61508.
4.5 Storage and transport
When storing and transporting the device, pack it so that it is reliably protected
against impact. The original packaging provides optimum protection.
5 Installation
5.1 Installation conditions
5.1.1 Dimensions
The dimensions of the device are provided in the 'Technical data' section of the Operating
Instructions.
5.1.2 Mounting location
The device is designed for installation on 35 mm (1.38 in) DIN rails in accordance with IEC
60715 (TH35).
NOTICE
‣When using in hazardous areas, the limit values of the certificates and approvals must
be observed.
For information on ambient conditions, see the "Technical data" section.

Installation RN22
10 Endress+Hauser
5.2 Installing the DIN rail bus connector
If using the DIN rail bus connector for the power supply, clip it onto the DIN rail
BEFORE mounting the device. Pay attention to the orientation of the module and DIN
rail bus connector when doing so: the snap-on clip should be at the bottom and the
connector piece on the left!
1. 2. 3.
A0041738
 2 Installing the DIN rail bus connector 12.5 mm (0.5 in)
1. Connect two or more DIN rail bus connectors together.
2. Attach the DIN rail bus connectors to the top of the DIN rail and allow them to click
into place on the underside of the DIN rail.
3. The DIN rail devices can now be installed.
5.3 Installing a DIN rail device
The device can be installed in any position (horizontal or vertical) on the DIN rail without
lateral clearance from neighboring devices. No tools are required for installation. The use
of end brackets (type "WEW 35/1" or similar) on the DIN rail is recommended to fix the
device.
If several devices are installed side by side, it is important to ensure that the
maximum side wall temperature of 85 °C (185 °F) is not exceeded. If this cannot be
guaranteed, mount the devices at a distance from one another or ensure sufficient
cooling.
1.
2.
3.
A0041736
 3 Installing on DIN rail
1. Position the top DIN rail groove at the top end of the DIN rail.
2. While holding the front of the device horizontally, lower it until you hear the locking
clip of the device click into place on the DIN rail.
3. Pull gently on the device to check if it is correctly mounted on the DIN rail.

RN22 Electrical connection
Endress+Hauser 11
5.4 Disassembling the DIN rail device
1.
2. 3.
A0039696
 4 Disassembling the DIN rail device
1. Insert a screwdriver into the tab of the DIN rail clip.
2. Use the screwdriver to pull down on the DIN rail clip as shown in the diagram.
3. Hold down the screwdriver to remove the device from the DIN rail.
6 Electrical connection
6.1 Connection conditions
A flat-blade screw driver is required to establish an electrical connection to screw or push-
in terminals.
0,5-0,6 Nm
5-7 lb In
7 mm (0,28")
AWG 24-14
0,2 -2,5 mm5 ² AWG 24-14
0,2 - ,5 mm5 2 ²
10 (0,39")mm
1.
2.
1.
1. 2.
3.
A0040201
 5 Electrical connection using screw terminals (left) and push-in terminals (right)
LCAUTION
Destruction of parts of the electronics
‣Switch off the power supply before installing or connecting the device.
NOTICE
Destruction or malfunction of parts of the electronics
‣ ESD - Electrostatic discharge. Protect the terminals and HART lugs on the front
from electrostatic discharge.
‣A shielded cable is recommended for HART communication. Observe grounding
concept of the plant.
For information on the connection data, see the "Technical data" section.

Electrical connection RN22
12 Endress+Hauser
6.2 Quick wiring guide
+24V
GND
n.c.
n.c.
n.c.
GND
+24V
6.1 6.2 5.2
Ch1 Ch2
4.1
2-W 2-W
4-W 4-W
4.2 5.1
Out
In
1.2 1.1
3.1 2.1
3.2 2.2
HART
Ch1
Ch2
+24V
GND
Out
In
Ch1 Ch2
4.1 4.2 5.1
GND
+24V
n.c.
n.c.
n.c.
HART
Ch1
2-W
4-W
1.2 1.1
3.1 2.1
3.2 2.2
A0040202
 6 Terminal assignment: 1- and 2-channel version (left), signal doubler (right)
HART communicators can be connected to the HART connecting points. Ensure an
adequate external resistance (≥230 Ω) in the output circuit.
6.3 Connecting the supply voltage
Power can be supplied via terminals 1.1 and 1.2 or via the DIN rail bus connector.
The device may only be powered by a power unit with an energy-limited circuit in
accordance with UL/EN/IEC 61010-1, Section 9.4 and the requirements of Table 18.
6.3.1 Using the power and error message module to supply power
It is recommended to use the RNF22 power and error message module to provide the
supply voltage to the DIN rail bus connector. An overall current of 3.75 A is possible with
this option.
6.3.2 Supply to the DIN rail bus connector via terminals
Devices installed side by side can be powered via the terminals of the device up to a total
current consumption of 400 mA. The connection is via the DIN rail bus connector. The
installation of a 630 mA fuse (semi-delay or slow-blow) upstream is recommended.
NOTICE
The simultaneous use of terminals and DIN rail bus connectors to supply power is not
permitted! The tapping of energy from the DIN rail bus connector for further
distribution is not permitted.
‣The supply voltage must never be connected directly to the DIN rail bus connector!

RN22 Electrical connection
Endress+Hauser 13
6.4 Post-connection check
Device condition and specifications Notes
Are the device or cables free from damage (visual
check)?
--
Do the ambient conditions match the device
specification (e.g. ambient temperature, measuring
range, etc.)?
See "Technical data"
Electrical connection Notes
Does the supply voltage match the specifications on
the nameplate?
Active barrier: U = e.g. 19.2 to 30 VDC
The device may only be powered by a power unit
with an energy-limited circuit.
Are the power supply and signal cables connected
correctly?
--
Are all the screw terminals well tightened and have
the connections of the push-in terminals been
checked?
--

Operation options RN22
14 Endress+Hauser
7 Operation options
7.1 Display and operating elements
1
2
3
5
6
4
A0040188
 7 Display and operating elements
1 Plug-in screw or push-in terminal
2 Green LED "On", power supply
3 Connection lugs for HART communication (channel 1)
4 Connection lugs for HART communication (channel 2, option)
5 DIN rail clip for DIN rail mounting
6 DIN rail bus connector (optional)
7.1.1 Local operation
Hardware settings / configuration
No manual hardware settings are required at the device for commissioning.
Attention must be paid to the different terminal assignment when connecting 2/4-wire
transmitters. At the output side, the connected system is detected and automatic switching
takes place between the active and passive mode.
8 Commissioning
8.1 Post-installation check
Before commissioning the device, ensure that all installation and post-connection checks
have been carried out.
NOTICE
‣Before commissioning the device, make sure that the supply voltage matches the
voltage specifications on the nameplate. Failure to perform these checks may result in
damage to the device caused by the incorrect supply voltage.
8.2 Switching on the device
Switch on supply voltage. The green LED display on the front of the device indicates that
the device is operational.

RN22 Diagnostics and troubleshooting
Endress+Hauser 15
9 Diagnostics and troubleshooting
9.1 General troubleshooting
Always start troubleshooting with the checklists below if faults occur after startup or
during operation. The checklists take you directly (via various queries) to the cause of the
problem and the appropriate remedial measures.
Due to its design, the device cannot be repaired. However, it is possible to send the
device in for examination. See the information in the "Return" section.
General errors
Error Possible cause Remedial action
Device is not responding. Supply voltage does not match the
specification on the nameplate.
Check the voltage directly using a
voltmeter and correct.
Connecting cables are not in contact
with the terminals.
Ensure electrical contact between the
cable and the terminal.
Electronics unit is defective. Replace the device.
HART communication is not
working.
Communication resistor missing or
incorrectly installed.
Install the communication resistor (≥
230 Ω) correctly.
HART modem is not properly
connected.
Connect HART modem correctly.
HART modem is not set to "HART". Set HART modem selector switch to
"HART".
The power LED on the DIN
rail device is not lit (green).
Power failure or insufficient supply
voltage.
Check the supply voltage and check if
wiring is correct.
10 Maintenance
No special maintenance work is required for the device.
Cleaning
A clean, dry cloth can be used to clean the device.
11 Repair
11.1 General information
Due to its design, the device cannot be repaired.

Technical data RN22
16 Endress+Hauser
11.2 Spare parts
Spare parts currently available for the device can be found online at:
http://www.products.endress.com/spareparts_consumables. Always quote the serial
number of the device when ordering spare parts!
Type Order code
Plug-in terminal set, 2-pin, DIN rail interfaces - screw 71505292
Plug-in terminal set, 2-pin, DIN rail interfaces - push-in 71505320
Front cover 12.5 mm, DIN rail housing (5 pcs per pack) 71505347
11.3 Return
The requirements for safe device return can vary depending on the device type and
national legislation.
1. Refer to the website for more information:
http://www.endress.com/support/return-material
2. Return the device if repairs or a factory calibration are required, or if the wrong
device was ordered or delivered.
11.4 Disposal
If required by the Directive 2012/19/EU on waste electrical and electronic equipment
(WEEE), the product is marked with the depicted symbol in order to minimize the
disposal of WEEE as unsorted municipal waste. Do not dispose of products bearing this
marking as unsorted municipal waste. Instead, return them to the manufacturer for
disposal under the applicable conditions.
12 Technical data
12.1 Function and system design
Product description RN22 Product design
Active barrier, 1-channel
• The active barrier is used for the transmission and galvanic isolation of 0/4 to 20 mA
signals. The device has an active/passive current input to which a 2- or 4-wire
transmitter can be directly connected. The output of the device can be operated actively
or passively. The current signal is then available to the PLC / controller or to other
instrumentation at plug-in screw terminals or optional push-in terminals.
• HART communication signals are transmitted bidirectionally by the device. Connecting
points for connecting HART communicators are integrated into the front of the device.
• The device is optionally available as an "associated apparatus", which allows devices to be
connected in Ex Zone 0/20 [ia] and operated in Ex Zone 2 [ec]. 2-wire transmitters are
supplied with power, and transmit analog 0/4 to 20 mA measured values from the
hazardous area to the non-hazardous area. These devices are accompanied by separate
Ex documentation, which is an integral part of this manual. Compliance with the
installation instructions and connection data in this documentation is mandatory!

RN22 Technical data
Endress+Hauser 17
Active barrier, 2-channel
With the "2-channel" option, the device has a second channel, which is galvanically isolated
from channel 1, while maintaining the same width. Otherwise, the function corresponds to
the 1-channel device.
Active barrier as signal doubler
With the signal doubler option, the active barrier is used for the galvanic isolation of a
0/4 to 20 mA signal, which is transmitted to two galvanically isolated outputs.
• Output 1 is HART-transparent. HART communication signals are transmitted
bidirectionally between the input and output 1.
• As output 2 contains a HART filter, only the galvanically isolated analog 4 to 20 mA
signal is transmitted.
Dependability We only provide a warranty if the device is installed and used as described in the
Operating Instructions.
12.2 Input
Version The following versions are available:
• 1-channel
• 2-channel
• Signal doubler
Input data, measuring
range
Input signal range (underrange / overrange) 0 to 22 mA
Function range, input signal 0/4 to 20 mA
Input voltage drop signal for 4-wire connection < 7 V at 20 mA
Transmitter supply voltage 17.5 V ±1 V at 20 mA
Open-circuit voltage: 24.5 V ±5 %
12.3 Output
Output data Output signal range (underrange / overrange) 0 to 22 mA
Function range, output signal 0/4 to 20 mA
Transmission behavior 1:1 to input signal
NAMUR NE 43 A current at the input that is valid according to
NAMUR NE 43 is transmitted to the output (within
the specified measuring uncertainty range)
Maximum load, active mode ≤ 500 Ω
Open-circuit voltage, active mode 17.5 V (± 5%)
Maximum load, passive mode Rmax = (Uext - 2 V) / 0.022 A
External voltage, passive mode Uext = 12 to 30 V
Transmissible communication protocols HART
Signal on alarm Line break in input Input 0 mA / output 0 mA
Line short circuit in input Input > 22 mA/ output > 22 mA

Technical data RN22
18 Endress+Hauser
Ex connection data See associated XA Safety Instructions
Galvanic isolation Power supply / input; power supply / output
Input / output; output / output
Testing voltage: 3 000 VAC 50 Hz, 1 min
Input / input Testing voltage: 500 VAC 50 Hz, 1 min
12.4 Power supply
Terminal assignment Quick wiring guide
+24V
GND
n.c.
n.c.
n.c.
GND
+24V
6.1 6.2 5.2
Ch1 Ch2
4.1
2-W 2-W
4-W 4-W
4.2 5.1
Out
In
1.2 1.1
3.1 2.1
3.2 2.2
HART
Ch1
Ch2
+24V
GND
Out
In
Ch1 Ch2
4.1 4.2 5.1
GND
+24V
n.c.
n.c.
n.c.
HART
Ch1
2-W
4-W
1.2 1.1
3.1 2.1
3.2 2.2
A0040202
 8 Terminal assignment: 1- and 2-channel version (left), signal doubler (right)
HART communicators can be connected to the HART connecting points. Ensure an
adequate external resistance (≥230 Ω) in the output circuit.
Connecting the supply
voltage
Power can be supplied via terminals 1.1 and 1.2 or via the DIN rail bus connector.
The device may only be powered by a power unit with an energy-limited circuit in
accordance with UL/EN/IEC 61010-1, Section 9.4 and the requirements of Table 18.
Using the power and error message module to supply power
It is recommended to use the RNF22 power and error message module to provide the
supply voltage to the DIN rail bus connector. An overall current of 3.75 A is possible with
this option.
Supply to the DIN rail bus connector via terminals
Devices installed side by side can be powered via the terminals of the device up to a total
current consumption of 400 mA. The connection is via the DIN rail bus connector. The
installation of a 630 mA fuse (semi-delay or slow-blow) upstream is recommended.
NOTICE
The simultaneous use of terminals and DIN rail bus connectors to supply power is not
permitted! The tapping of energy from the DIN rail bus connector for further
distribution is not permitted.
‣The supply voltage must never be connected directly to the DIN rail bus connector!

RN22 Technical data
Endress+Hauser 19
Performance characteristics Power supply 1)
Supply voltage 24 VDC (-20% / +25%)
Supply current to the DIN rail bus
connector
max. 400 mA
Power consumption at 24 VDC 1-channel: ≤ 1.5 W (20 mA) / ≤ 1.6 W (22 mA)
2-channel: ≤ 3 W (20 mA) / ≤ 3.2 W (22 mA)
Signal doubler: ≤ 2.4 W (20 mA) / ≤ 2.5 W (22 mA)
Current consumption at 24 VDC 1-channel: ≤ 0.07 A (20 mA) / ≤ 0.07 A (22 mA)
2-channel: ≤ 0.13 A (20 mA) / ≤ 0.14 A (22 mA)
Signal doubler: ≤ 0.1 A (20 mA) / ≤ 0.11 A (22 mA)
Power loss at 24 VDC 1-channel: ≤ 1.2 W (20 mA) / ≤ 1.3 W (22 mA)
2-channel: ≤ 2.4 W (20 mA) / ≤ 2.5 W (22 mA)
Signal doubler: ≤ 2.1 W (20 mA) / ≤ 2.2 W (22 mA)
1) The data apply for the following operating scenario: input active / output active / output load 0 Ω. When
external voltages are connected to the output, the power loss in the device may increase. The power loss in
the device can be reduced by connecting an external output load.
Power supply failure To meet SIL and NE21 requirements, voltage interruptions of up to 20 ms must be bridged
with a suitable power supply.
Terminals A flat-blade screwdriver is required to establish an electrical connection to screw or push-
in terminals.
0,5-0,6 Nm
5-7 lb In
7 mm (0,28")
AWG 24-14
0,2 -2,5 mm5 ² AWG 24-14
0,2 - ,5 mm5 2 ²
10 (0,39")mm
1.
2.
1.
1. 2.
3.
A0040201
 9 Electrical connection using screw terminals (left) and push-in terminals (right)
Terminal design Cable design Cable cross-section
Screw terminals
Tightening torque: minimum 0.5
Nm/maximum 0.6 Nm
Rigid or flexible
(Stripping length = 7 mm (0.28 in) 0.2 to 2.5 mm² (24 to 14 AWG)
Flexible with wire end ferrules
(with or without plastic ferrule) 0.25 to 2.5 mm² (24 to 14 AWG)
Push-in spring terminals
Rigid or flexible
(Stripping length =
10 mm (0.39 in)
0.2 to 2.5 mm² (24 to 14 AWG)
Flexible with wire end ferrules
(with or without plastic ferrule)
0.25 to 2.5 mm² (24 to 14 AWG)
Cable specification A shielded cable is recommended for HART communication. Observe grounding concept of
the plant.

Technical data RN22
20 Endress+Hauser
12.5 Performance characteristics
Response time Step response (10 to 90 %) ≤ 1 ms
Step response (10 to 90 %) signal doubler output 2
HART filter
≤ 50 ms
Reference operating
conditions
• Calibration temperature: +25 °C ±3 K (77 °F ±5.4 °F)
• Supply voltage: 24 VDC / 230 VAC
• Output load: 225 Ω
• External output voltage (passive output): 20 VDC
• Warm-up: > 1 h
Maximum measured error Accuracies
Transmission error < 0.1 % / of full scale value (< 20 µA)
Temperature coefficient < 0.01 % /K
Long-term drift Max. ±0.1 %/year (of full scale value)
12.6 Installation
Mounting location The device is designed for installation on 35 mm (1.38 in) DIN rails in accordance with IEC
60715 (TH35).
NOTICE
‣When using in hazardous areas, the limit values of the certificates and approvals must
be observed.
For information on ambient conditions, see the "Technical data" section.
Installing a DIN rail device The device can be installed in any position (horizontal or vertical) on the DIN rail without
lateral clearance from neighboring devices. No tools are required for installation. The use
of end brackets (type "WEW 35/1" or similar) on the DIN rail is recommended to fix the
device.
If several devices are installed side by side, it is important to ensure that the
maximum side wall temperature of 85 °C (185 °F) is not exceeded. If this cannot be
guaranteed, mount the devices at a distance from one another or ensure sufficient
cooling.