Endress+Hauser RMS621 User manual

BA182R/09/en/08.05
51009170
Software version:
3.0
Operating Instructions
RMS621
Energy Manager

RMS621
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Brief overview
For quick and easy commissioning:
Safety instructions Page 8
⇓
Installation Page 11
⇓
Wiring Page 13
⇓
Display and operating elements Page 23
⇓
Commissioning Page 28
Quick start via the navigator to device configuration for standard operation.
Device configuration - explanation and use of all configurable device
functions with the associated value ranges and settings.
Application example - configuration of the device.
Applications for the Energy Manager
The device compensates flow measurements of steam and water according to the international standard for calculation
IAPWS IF-97 (ASME tables).

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Brief operating instructions
"Caution!
The information contained in these Operating Instructions serves as a guide to help you commission
your device easily, i.e. the most important settings are listed here but special functions (e.g. tables,
corrections etc.) are not.
Configuring a measurement - Set-up example
Example 1: Steam heat (or steam mass)
Sensors: DPO10 (orifice), Cerabar T, TR 10
1. Connect device to the power source (terminal L/L+, 230 V)
2. Press any key →Setup (all parameters)
3. Basic set-up
Date-time (set up date and time) ÆZ
Select system eng. units (select metric or American)
4. Flow inputs (flow 1)
Flow meter: Differential pressure
Diff. device: Orifice corner tap
Signal: 4 to20 mA
Terminals: Select A10 and connect DP transmitter to terminals: A10(-)/82(+) (because of
passive signal)
Curve: linear (also set up linear curve at the DP transmitter)
Set up start- and end-value (in mbar!)
Tube data: enter internal tube diameter and diameter ratio (ß) as found on the maufacturers
data sheet.
"Caution!
If tube data is not known, for flow meter: select operating volume
Curve: linear (set up square rooted curve on the DP transmitter)
Set up start- and end-values (m3/h)
5. Pressure input (Pressure 1)
Signal type: e.g. 4 to 20 mA
Terminals: Select A110 and connect Cerabar T to terminals: A110(-)/A83(+) (passive signal)
Type: Select absolute (-pressure measurement) or relative (-pressure measurement)
Set up start- and end-values of the pressure transmitter ÆZ
6. Temperature inputs (temp. 1.1)
Signal type: Pt100
Sensor type: 3- or 4-wire
Select terminals E1-6 and connect Pt100 ÆZÆZ.
7. Application
Application 1: Steam heat
Steam type: super heated steam
Allocate flow 1, pressure 1 and temp. 1.1 to the steam measurement.
Fig. 1: Temperature sensor connection, e.g. to input 1 (Slot E I)
Pos. 1: 4-wire input
Pos. 2: 3-wire input
Pos. 3: 3-wire input e.g. optional
temp. expansion card (Slot B I)

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8. Display
Group 1
Display mask: 3 values
Value 1 (...4): Mass flow, Mass sum, Heat sum ÆZ
Group 2: select to above system e.g. flow 1, pressure 1, temperature 1.1, heat flow 1.
9. Exit set-up
Exit set-up by operating ESC Za number of times and acknowledging with F.
Display
By operating any key you can enter the main menu and select the required group including all the
relative display values: Display -> Group -> Group 1. All can also be displayed in an automatic scroll
function: Setup -> Display -> Scrolled display (scroll using the arrow under group 6).
If a fault occurs the display automatically changes colour (blue/red). Detailed fault finding and
elimination can be found in the relative chapter of these operating instructions.
Example 2: Water heat difference
Sensors: 2 x TST90, Promag 50
1. Connect device to the power source (terminal L/L+, 230 V)
2. Press any key →Menu →Setup (all parameters)
3. Basic set-up
Date-time (set up date and time) ÆZ
Select system eng. units (metric or American)
4. Flow input (flow 1)
Flow meter: Operating volume
Signal type: 4 to20 mA
Terminals: select A10 and connect the Prowirl to terminals: A10(+)/11(-) (active signal)
Set up start- and end-values
5. Temperature inputs (temp. 1.1 and temp. 1.2)
Signal type: Pt100
Sensor type: 3- or 4-wire
Terminals: select E1-6 and connect TST90 (temp. 1.1) ÆZ
Terminals: select E3-8 and connect TST90 (temp. 1.2)ÆZÆZ
6. Applications
Application 1: Water heat difference
Operating mode: Heating
Select "Flow 1"
Installation point: Cold (means return)
Allocate temperature sensors 1.1 and 1.2 to heat and cooling section.
7. Display
Group 1
Display mask: 3 values
Value 1 (...4): Flow 1, heat flow 1 and mass sum 1 ÆZ
Fig. 2: Temperature sensor connection, e.g. to input 1 (Slot E I)
Pos. 1: 4-wire input
Pos. 2: 3-wire input
Pos. 3: 3-wire input e.g. optional
temp. expansion card (Slot B I)

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Group 2: select to above system e.g. temp. 1.1, temp. 1.2, mass flow 1, mass sum 1.
8. Exit set-up
Exit set-up by operating ESC Za number of times and acknowledging with F.
Display
By operating any key you can enter the main menu and select the required group including all the
relative display values: Display -> Group -> Group 1. All groups can also be displayed in an
automatic scroll function: Setup -> Display -> Scrolled display (scroll using the arrow under group
6).
If a fault occurs the display automatically changes colour (blue/red). Detailed fault finding and
elimination can be found in the relative chapter of these operating instructions.
An example of steam mass measurement using a Prowirl 77 can be found in the appendix of this
operating manual.
Example 3
!Note!
You will find a further example for a steam mass calculation using a Prowirl 77 in chapter 6.4.1 of
the operating instructions.
Basic application settings
The values shown are only an indication in order to simplify the commissioning of the device, this
means that only the most necessary settings are shown. Special functions (e.g. tables, corrections,
etc.) are not shown.
Water applications
Input values: Flow, temperature 1, (temperature 2)
Only one temperature is required for water heat quantity. A direction signal teriminal is required on
changing flow direction (bi-directional operating mode).
Flow
Pulse/PFM (e.g. ProWirl) Analog (e.g. Promag) Differential pressure (e.g. Orifice)
Flow input Flow input Special flow meters
Flow meter: Operating volume Flow meter: Operating volume Differential pressure/Orifice/water
Terminals:
– Flow meter with active signal connect to e.g. terminals A10(+)/11(-).
– Flow meter with passive signal select e.g. terminals A10 and connect to terminals A10(-)/82(+). Terminal 82 is 24 V sensor power supply.
k factor Start/end value (m3/h) Start/end value (mbar)
Temperature
Select signal type and connect sensor(s) (see example). 2 temperature sensors are required for heat differential measurements.
Application
Application: Medium: water/steam
Liquid application: e.g. water heat difference
Operating mode: e.g. heating (this means inflow warm, return cold)
Allocate sensors for flow and pressure measurement
Allocate installation point, T warm/cold

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Steam applications
Input variables: flow, pressure, temperature1, (temperature2)
Flow
Pulse/PFM (e.g. Vortex) Analog (e.g. Vortex) Differential pressure (e.g. orifice)
Flow input Flow input Special flow meters
Flow sensor: operating volume Flow sensor: operating volume Differential pressure/orifice.../steam
Terminal connection
– Flow transmitter with active signal: e.g. select terminal A10 and connect flow meter to terminal A10(+)/11(-).
– Flow transmitter with passive signal: e.g. select terminal A10 and connect flow meter to terminal A10(-)/82(+). Terminal 82 is 24 V sensor power supply.
K-factor Start value/end value: ... (m3/h) Start value/end value: ...(mbar)
Pressure
Select signal type and terminal connection and connect sensor (see example).
Type: Relative or absolute pressure?
Temperature
Select signal type and connect sensor(s) (see example). 2 temperature sensors are required for steam difference measurements.
Application
Application(1); medium: water/steam
Application: e.g. steam mass/heat
Steam type: e.g. superheated
Allocate sensors for flow, pressure and temperature measurement

RMS621 Table of contents
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Table of contents
1 Safety instructions . . . . . . . . . . . . . . . . 8
1.1 Designated use . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.2 Installation, commissioning and operation . . . . . . . . 8
1.3 Operational safety . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.4 Return . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.5 Notes on safety conventions and icons . . . . . . . . . . . 9
2 Identification . . . . . . . . . . . . . . . . . . . 10
2.1 Device designation . . . . . . . . . . . . . . . . . . . . . . . . 10
2.2 Scope of delivery . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.3 Certificates and approvals . . . . . . . . . . . . . . . . . . . 10
3 Installation . . . . . . . . . . . . . . . . . . . . . 11
3.1 Installation conditions . . . . . . . . . . . . . . . . . . . . . . 11
3.2 Installation instructions . . . . . . . . . . . . . . . . . . . . . 11
3.3 Post-installation check . . . . . . . . . . . . . . . . . . . . . . 12
4 Wiring . . . . . . . . . . . . . . . . . . . . . . . . 13
4.1 Quick wiring guide . . . . . . . . . . . . . . . . . . . . . . . . 13
4.2 Connecting the measuring unit . . . . . . . . . . . . . . 14
4.3 Post-connection check . . . . . . . . . . . . . . . . . . . . . . 22
5 Operation . . . . . . . . . . . . . . . . . . . . . . 23
5.1 Display and operating elements . . . . . . . . . . . . . . . 23
5.2 Local operation . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
5.3 Error message display . . . . . . . . . . . . . . . . . . . . . . 26
5.4 Communication . . . . . . . . . . . . . . . . . . . . . . . . . . 27
6 Commissioning. . . . . . . . . . . . . . . . . . 28
6.1 Function check . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
6.2 Switching on the measuring device . . . . . . . . . . . 28
6.3 Device configuration . . . . . . . . . . . . . . . . . . . . . . . 29
6.4 User-specific applications . . . . . . . . . . . . . . . . . . . . 51
7 Maintenance. . . . . . . . . . . . . . . . . . . . 53
8 Accessories. . . . . . . . . . . . . . . . . . . . . 53
9 Trouble-shooting . . . . . . . . . . . . . . . . 54
9.1 Trouble-shooting instructions . . . . . . . . . . . . . . . . 54
9.2 System error messages . . . . . . . . . . . . . . . . . . . . . . 54
9.3 Process error messages . . . . . . . . . . . . . . . . . . . . . 55
9.4 Spare parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
9.5 Return . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
9.6 Disposal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
10 Technical data . . . . . . . . . . . . . . . . . . 60
11 Appendix . . . . . . . . . . . . . . . . . . . . . . 67
11.1 Definition of important system units . . . . . . . . . . . 67
11.2 Flow measurement configuration . . . . . . . . . . . . 67
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

Safety instructions RMS621
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1 Safety instructions
Safe operation of the Flow and Energy Manager is only guaranteed if these Operating Instructions
have been read and the safety instructions have been observed.
1.1 Designated use
The Energy Manager is a unit for monitoring energy and flows in water and steam applications. It
can be used in both heating and cooling systems. A large variety of different flow sensors,
temperature and pressure sensors can be connected to the unit. The energy manager accepts the
current/PFM/pulse or temperature signals from the individual sensors and from these calculates
the liquid and energy values:
–Volumeandmass
– Heat flow or energy
– Heat energy differential
all using the international calculation standard IAPWS-IF 97.
– The unit is classified as additional equipment and may not be used in a hazardous area.
– The manufacturer cannot take responsibility for any damage caused by misuse of the unit. It is not
permitted to make any changes or reconstruction to the unit.
– The energy manager has been designed for use in an industrial environment and may only be used
in an appropriately installed condition.
1.2 Installation, commissioning and operation
The unit is safely manufactured using state-of-the-art technology and complies with the respective
EU regulations. The unit could be dangerous if it is incorrectly installed or used.
Mechanical and electrical installation, commissioning and maintenance of the unit must only be
carried out by skilled and qualified personnel. The skilled personnel must have read and understood
these operating instructions and followed them carefully. Always make sure that the unit is correctly
connected following the electrical connection diagrams (see Chap. 4 "Electrical installation"). When
the unit covers are removed, all electrical contact protection is lost (danger of electrical shock). The
housing must only be opened by qualified skilled personnel.
1.3 Operational safety
Technical advancement
The manufacturer reserves the right to improve and update the technical details. For details of
improvements or additions to these instructions, please contact your local sales organisation.
1.4 Return
For a return, e.g. in case of repair, the device must be sent in protective packaging. The original
packaging offers the best protection. Repairs must only be carried out by your supplier's service
organisation.
!Note!
When sending for repair, please enclose a note with a description of the error and the application.

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1.5 Notes on safety conventions and icons
The safety instructions in these Operating Instructions are labelled with the following safety icons
and symbols:
"Caution!
This symbol draws attention to activities or procedures that can lead to defective operation or to
destruction of the device if not carried out properly.
#Warning!
This symbol draws attention to activities or procedures that can lead to injuries to persons, to a safety
risk or to destruction of the device if not carried out properly.
!Note!
This symbol draws attention to activities or procedures that have an indirect effect on operation, or
can trigger an unforeseen device reaction if not carried out properly.

Identification RMS621
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2 Identification
2.1 Device designation
2.1.1 Nameplate
Compare the nameplate on the device with the following diagram:
Fig. 3: Energy manager legend plate (example)
1 Order code and unit series number
2 Protection class and allowable ambient temperature
3 Power supply
4 Temperature sensor input with measurement range
5 Approvals with accuracy details
6 Available in/outputs
2.2 Scope of delivery
The scope of delivery of the Energy Manager comprises:
• Energy Manager for top-hat rail mounting
• Operating Instructions
• CD-ROM with PC configuration software and interface cable RS232 (optional)
• Remote display for panel mounting (optional)
• Extension cards (optional)
!Note!
Please note the device accessories in Section 8 ’Accessories’.
2.3 Certificates and approvals
CE mark, declaration of conformity
The Energy Manager has been constructed and tested to state-of-the-art operational safety standards
and left the factory in perfect condition as regards technical safety. The device meets the relevant
standards and directives as per EN 61 010 "Safety requirements for electrical equipment for
measurement, control and laboratory use".
Thus, the device described in these Operating Instructions meets the legal requirements of the EU
Directives. The manufacturer confirms successful testing of the device by affixing to it the CE mark.
The device has been developed in accordance with the requirements of the Directives OIML R75
(heat counter) and EN-1434 (flow measurement).

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3 Installation
3.1 Installation conditions
The permitted ambient temperature (see "Technical data" Section) must be observed when
installing and operating. The device must be protected against the effects of heat.
3.1.1 Dimensions
Observe the device length of 135 mm (corresponds to 8TE). More dimensions can be found in
Section 10 "Technical data".
3.1.2 Mounting location
Top-hat rail mounting as per EN 50 022-35 in the cabinet. The mounting location must be free from
vibrations.
3.1.3 Orientation
No restrictions.
3.2 Installation instructions
First remove the plug-in terminals from the device slots. Now snap the housing onto the top-hat rail
by firstly hanging the device on the top-hat rail and then pressing it down gently until it engages
(see Fig. 4, item 1 and 2).
Fig. 4: Mounting device on top-hat rail

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3.2.1 Installing extension cards
You can equip the device with various extension cards. A maximum of three slots are available in
the device for this. The slots for the extension cards are marked with B, C and D (→Fig. 5) on the
device.
1. Make sure that the device is not connected to the power supply when installing and removing
an extension card.
2. Remove the blanking cover from the slot (B, C or D) of the basic unit by pressing together the
catches on the bottom of the Energy Manager (see Fig. 5, item 2), while at the same time
pressing in the catch on the rear of the housing (e.g. with a screwdriver) (see Fig. 5, item 1).
Now you can pull the blanking cover up out of the basic unit.
3. Insert the extension card into the basic unit from above. The extension card is not correctly
installed until the catches on the bottom and rear of the device (see Fig. 5, items 1 and 2) lock
into place. Ensure that the input terminals of the extension card are on top and the connection
terminals are pointing to the front, as with the basic unit.
4. The device automatically recognises the new extension card once the device has been
corrected wired and has been commissioned (see ’Commissioning’ Section).
!Note!
If you remove an extension card and do not replace it with another card, you must seal the empty
slot with a blanking cover.
Fig. 5: Installing an extension card (example)
Item 1: catch on the rear of the device
Item 2: catches on the bottom of the device
Items A - E: identifier for slot assignment
3.3 Post-installation check
When using extension cards, ensure that the cards are sitting correctly in the device slots.
!Note!
When using the device as a heat counter, observe the installation instructions EN 1434 Part 6 when
mounting the device. This also includes the installation of the flow and temperature sensors.

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4 Wiring
4.1 Quick wiring guide
Fig. 6: Slot assignment (basic unit)
Terminal assignment
Terminal (item no.) Terminal assignment Slot Input
10 + 0/4 to 20 mA/PFM/pulse input 1 A top, front (A I) Current/PFM/pulse input 1
11 Ground for 0/4 to 20 mA/PFM/pulse input
81 Sensor power supply ground 1
82 24 V sensor power supply 1
110 + 0/4 to 20 mA/PFM/pulse input 2 A top, rear (A II) Current/PFM/pulse input 2
11 Ground for 0/4 to 20 mA/PFM/pulse input
81 Sensor power supply ground 2
83 24 V sensor power supply 2
1 + RTD power supply 1 E top, front (E I) RTD input 1
2 - RTD power supply 1
5 + RTD sensor 1
6 - RTD sensor 1
3 + RTD power supply 2 E top, rear (E II) RTD input 2
4 - RTD power supply 2
7 + RTD sensor 2
8 - RTD sensor 2
Terminal (item no.) Terminal assignment Slot Output - interface
101 + RxTx 1 E bottom, front (E III) RS485
102 - RxTx 1
103 + RxTx 2 RS485 (optional)
104 - RxTx 2

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!Note!
The current/PFM/pulse inputs or the RTD inputs in the same slot are not galvanically isolated.
There is a separation voltage of 500 V between the aforementioned inputs and outputs in various
slots. Terminals with the same second digit are jumpered internally (Terminals 11 and 81).
4.2 Connecting the measuring unit
"Caution!
Do not install or wire the device when it is connected to the power supply. Not conforming with
this can lead to the destruction of electronic components.
131 + 0/4 to 20 mA/pulse output 1 E bottom, rear (E IV) Current/pulse output 1
132 - 0/4 to 20 mA/pulse output 1
133 + 0/4 to 20 mA/pulse output 2 Current/pulse output 2
134 - 0/4 to 20 mA/pulse output 2
52 Relay Common (COM) A bottom, front (A III) Relay 1
53 Relay normally open (NO)
91 Sensor power supply ground Additional sensor power supply
92 + 24 V sensor power supply
L/L+ L for AC
L+ for DC
A bottom, rear (A IV)
Power supply
N/L- N for AC
L- for DC
Connection overview, top (inputs) Connection overview, bottom (outputs, interfaces)

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4.2.1 Power supply connection
"Caution!
• Before wiring the device, ensure that the supply voltage corresponds to the specification on the
nameplate.
• For the 90 to 250 V AC version (mains connection), a switch marked as a separator, as well as an
overvoltage organ (rated current ≤10 A), must be fitted in the supply line near the device (easy
to reach).
Fig. 7: Power supply connection
4.2.2 Connecting external sensors
!Note!
Active and passive sensors with analog, PFM or pulse signal and RTD sensors can be attached to the
device.
Depending on the type of signal of the sensor in question, the terminals can be freely selected which
means the Energy Manager can be used with great flexibility. This means that the terminals are not
fixed to the sensor type, e.g. flow sensor-terminal 11, pressure sensor-terminal 12 etc. If the device
is used as a heat counter in accordance with EN 1434, the connection regulations mentioned there
apply.
Active sensors
Connection method for an active sensor (i.e. external power supply).
Fig. 8: Connecting an active sensor, e.g. to input 1 (Slot A I).
Item 1: pulse signal
Item 2: PFM signal
Item 3: 2-wire transmitter (4 to 20 mA)
Item 4: active sensor connection, e.g. optional Universal extension card in slot B (slot B I, →Fig. 13)

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Passive sensors
Connection method for sensors which are supplied with power by means of the sensor power supply
integrated in the device.
Fig. 9: Connecting a passive sensor, e.g. to input 1 (slot A I).
Item 1: pulse signal
Item 2: PFM signal
Item 3: 2-wire transmitter (4-20 mA)
Item 4: passive sensor connection, e.g. optional Universal extension card in slot B (slot B I, →Fig. 13)
Temperature sensors
Connection for Pt100, Pt500 and Pt1000
!Note!
Terminals 1 and 5 (3 and 7) must be jumpered when connecting 3-wire sensors (see Fig. 6).
Abb. 10: Connecting a temperature sensor, e.g. to input 1 (slot E I)
Item 1: 4-wire input
Item 2: 3-wire input
Item 3: 3-wire input, e.g. optional temperature extension card in slot B (slot B I, →Fig. 13)
E+H-specific devices
Flow sensors with PFM output
!Note!
Set the Prowirl measuring device to PFM output (ÆFU 20:
ON, PF)

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Flow sensor with open collector output
!Note!
Select an appropriate dropping resistor R, so that
Imax. = 20 mA is not exceeded.
Flow sensor with passive current output (4 to 20 mA)
Flow sensor with active current output (0/4 to 20 mA)
Flow sensor with active current output and passive
frequency output (measurement of bidirectional flow)
!Note!
Select an appropriate dropping resistor R, so that
Imax. = 20 mA is not exceeded.
• Item A: direction signal
•ItemB:flow
Temperature sensor via temperature head transmitter
(4 to 20 mA)

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4.2.3 Connection of outputs
The device has two galvanically isolated outputs which can be configured as an analog output or an
active pulse output. In addition, an output for connecting a relay and transmitter power supply is
available. The number of outputs increases accordingly when the extension cards are installed
(see Section 4.2.4).
Fig. 11: Connection of outputs
Item 1: pulse and current outputs (active)
Item 2: passive pulse output (open collector)
Item 3: relay output (NO), e.g. slot A III (slot BIII, CIII, DIII on optional extension card)
Item 4: transmitter power supply (transmitter power supply unit) output
Interface connection
•RS232 connection
The RS232 is contacted by means of the interface cable and the jack socket on the front of the
housing.
•RS485 connection
•Optional: additional RS485 interface
Plug-in terminals 103/104, the interface is only active as long as the RS232 interface is not used.
•PROFIBUS connection
Optional connection of Energy Manager to PROFIBUS DP via the serial RS485 interface with the
external module HMS AnyBus Communicator for Profibus (see Section 8 ’Accessories’).
Fig. 12: Interface connection
Pressure sensor with passive current output (4 to
20 mA)

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4.2.4 Extension card connection
Fig. 13: Extension card with terminals
Terminal assignment of Universal extension card
Terminal assignment of temperature extension card
Terminal (item no..) Terminal assignment Slot Input and output
182 24 V sensor power supply 1 B, C, D top, front (B I, C
I, D I)
Current/PFM/pulse input 1
181 Sensor power supply ground 1
112 + 0/4 to 20 mA/PFM/pulse input 1
111 Ground for 0/4 to 20 mA/PFM/pulse input
183 24 V sensor power supply 2 B, C, D top, rear (B II, C
II, D II)
Current/PFM/pulse input 2
181 Sensor power supply ground 2
113 + 0/4 to 20 mA/PFM/pulse input 2
111 Ground for 0/4 to 20 mA/PFM/pulse input
142 Relay 1 Common (COM) B, C, D bottom, front (B
III, C III, D III)
Relay 1
143 Relay 1 normally open (NO)
152 Relay 2 Common (COM) Relay 2
153 Relay 2 normally open (NO)
131 + 0/4 to 20 mA/pulse output 1 B, C, D bottom, centre (B
IV, C IV, D IV)
Current/pulse output 1 active
132 - 0/4 to 20 mA/pulse output 1
133 + 0/4 to 20 mA/pulse output 2 Current/pulse output 2 active
134 - 0/4 to 20 mA/pulse output 2
135 + pulse output 3 (open collector) B, C, D bottom, rear (B V,
C V, D V)
Passive pulse output
136 - pulse output 3
137 + pulse output 4 (open collector) Passive pulse output
138 - pulse output 4
Terminal (item no..) Terminal assignment Slot Input and output
117 + RTD power supply 1 B, C, D top, front (B I, C
I, D I)
RTD input 1
116 + RTD sensor 1
115 - RTD sensor 1
114 - RTD power supply 1

Wiring RMS621
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!Note!
The current/PFM/pulse inputs or the RTD inputs in the same slot are not galvanically isolated.
There is a separation voltage of 500 V between the aforementioned inputs and outputs in various
slots. Terminals with the same second digit are jumpered internally. (Terminals 111 and 181)
4.2.5 Connecting remote display/operating unit
Functional description
The remote display is an innovative addition to the powerful RMX 621 top-hat rail devices. The user
has the opportunity to optimally install the arithmetic unit to suit the installation and mount the
display and operating unit in a user-friendly way at easily accessible locations. The display can be
connected to both a top-hat rail device without, as well as a top-hat rail device with, an installed
display/operating unit. A 4-pin cable is supplied to connect the remote display with the basic unit;
other components are not necessary.
!Note!
Only one display/operating element can be attached to a top-hat rail device and vice versa (point-
to-point).
121 + RTD power supply 2 B, C, D top, rear (B II, C
II, D II)
RTD input 2
120 + RTD sensor 2
119 - RTD sensor 2
118 - RTD power supply 2
142 Relay 1 Common (COM) B, C, D bottom, front (B
III, C III, D III)
Relay 1
143 Relay 1 normally open (NO)
152 Relay 2 Common (COM) Relay 2
153 Relay 2 normally open (NO)
131 + 0/4 to 20 mA/pulse output 1 B, C, D bottom, centre (B
IV, C IV, D IV)
Current/pulse output 1 active
132 - 0/4 to 20 mA/pulse output 1
133 + 0/4 to 20 mA/pulse output 2 Current/pulse output 2 active
134 - 0/4 to 20 mA/pulse output 2
135 + pulse output 3 (open collector) B, C, D bottom, rear (B V,
C V, D V)
Passive pulse output
136 - pulse output 3
137 + pulse output 4 (open collector) Passive pulse output
138 - pulse output 4
Terminal (item no..) Terminal assignment Slot Input and output