Siemens RMB795B Operator's manual

s Infrastructure & Cities
Synco700
Central control unit RMB795B
For room controllers RXB/RXL and room thermostats RDG/RDF/RDU
Basic documentation
CE1P3122en
18.01.2012
Building Technologies
CE1P3122en
18.01.2012
Building Technologies

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Siemens Central control unit RMB795B CE1P3122en
Building Technologies 18.01.2012
Siemens Switzerland Ltd
Sector Infrastructure & Cities
Building Technologies Division
Gubelstrasse 22
6301 Zug
Schweiz
Phone [phone]
www.siemens.com/sbt
© 2004-2012 Siemens Switzerland Ltd
Subject to change

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Contents
1Overview ................................................................................................10
1.1 Central control unit RMB795B ................................................................10
1.2 Product range..........................................................................................10
1.3 Synco™ 700 topology.............................................................................12
1.4 Equipment combinations.........................................................................12
1.5 Product documentation ...........................................................................13
1.6 Output .....................................................................................................13
1.7 Important notes .......................................................................................14
2Operation ...............................................................................................16
2.1 Operation without operator unit...............................................................16
2.2 Operation with operator unit....................................................................17
2.2.1 Operator unit functions............................................................................17
2.2.2 Operating concept...................................................................................17
2.2.3 Operating levels ......................................................................................19
2.2.4 Access levels ..........................................................................................19
3Room group philosophy ......................................................................21
3.1 What is a room group?............................................................................21
3.2 Application example................................................................................21
3.3 Implement application example ..............................................................24
4Engineering and commissioning guidelines .....................................26
5Commissioning .....................................................................................30
5.1 Before you start.......................................................................................30
5.1.1 Safety notes ............................................................................................30
5.1.2 Potential impact of power failures ...........................................................30
5.2 Start commissioning................................................................................31
5.2.1 Start during initial power-up ....................................................................31
5.2.2 Start from the main menu........................................................................32
5.3 Basic configuration..................................................................................32
5.3.1 Select basic type "B" ...............................................................................32
5.3.2 Assign extension modules ......................................................................33
5.3.3 Settings ...................................................................................................33
5.4 Create free configuration ........................................................................34
5.5 Wiring test ...............................................................................................34
5.6 Exit commissioning .................................................................................35
5.7 Back up data ...........................................................................................35
5.8 Exit password level .................................................................................36
5.9 View device information ..........................................................................36
5.10 Mark an intervention ...............................................................................36
6General settings....................................................................................38
6.1 Time of day and date ..............................................................................38
6.1.1 Operating principle..................................................................................38
6.1.2 Communication .......................................................................................39
6.1.3 Troubleshooting ......................................................................................40

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6.2 Select language ......................................................................................40
6.3 Select temperature unit ...........................................................................41
6.4 Operator unit display contrast .................................................................41
6.5 Text entry.................................................................................................41
6.5.1 Device name ...........................................................................................41
6.5.2 File name.................................................................................................41
6.5.3 Electronic business card .........................................................................41
6.5.4 Editable text.............................................................................................42
7Inputs......................................................................................................43
7.1 Universal inputs (Xx) ...............................................................................43
7.1.1 General settings ......................................................................................43
7.1.2 Activate function......................................................................................43
7.1.3 Cause ......................................................................................................44
7.1.4 Input terminal simulation .........................................................................44
7.1.5 Troubleshooting.......................................................................................45
7.1.6 Functional check / wiring test ..................................................................45
7.2 Analog inputs (Xx)...................................................................................45
7.2.1 Activation and type..................................................................................45
7.2.2 Measuring range .....................................................................................46
7.2.3 Measured value correction......................................................................46
7.2.4 Connection examples for sensors...........................................................47
7.2.5 Troubleshooting.......................................................................................48
7.2.6 Multiple use of sensors ...........................................................................49
7.3 Digital inputs (Xx) ....................................................................................49
7.3.1 Use and activation...................................................................................49
7.3.2 Normally closed.......................................................................................49
7.3.3 Texts for logical states 0 and 1................................................................49
7.3.4 Connection example ...............................................................................50
7.3.5 Troubleshooting.......................................................................................50
7.4 Pulse .......................................................................................................51
7.4.1 Activate function......................................................................................51
7.4.2 Connection diagram ................................................................................51
7.5 Outside temperature ...............................................................................52
7.5.1 Connection choices.................................................................................52
7.5.2 Outside temperature at terminal..............................................................52
7.5.3 Outside temperature via bus ...................................................................53
7.5.4 Outside temperature simulation ..............................................................53
7.5.5 Troubleshooting.......................................................................................53
7.6 Texts ........................................................................................................54
8Function block: "Room group"............................................................56
8.1 Overview .................................................................................................56
8.2 Activate function block ............................................................................57
8.3 Room operating modes per room group .................................................58
8.3.1 Room operating mode selector...............................................................58
8.3.2 Room mode selection via digital inputs...................................................59
8.3.3 Room operating mode selection using room unit QAW740 ....................62
8.3.4 Release room unit QAX3x.x for time switch operating mode Economy .62
8.3.5 7-day time switch ....................................................................................63
8.3.6 Holidays/special days..............................................................................64
8.3.7 Room operating mode outputs................................................................67
8.3.8 Functional check / wiring test ..................................................................69

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8.4 Setpoints and setpoint adjustments ........................................................69
8.4.1 Setpoints .................................................................................................69
8.4.2 Application example, setpoint priority, setpoint master...........................70
8.4.3 Summer/winter compensation ................................................................71
8.4.4 Relate setpoint adjustment using room unit QAW740 ............................72
8.5 Temperatures "Reference rooms"...........................................................73
8.6 Temperature supervision.........................................................................73
8.7 Optimum start control for individual room controllers .............................74
8.7.1 Activate function......................................................................................75
8.7.2 Operating principle optimum start control ...............................................75
8.7.3 Troubleshooting ......................................................................................76
8.8 Control functions for individual room controllers.....................................76
8.8.1 Priorities ..................................................................................................78
8.9 Night cooling ...........................................................................................78
8.9.1 Activate function......................................................................................78
8.9.2 Operating principle..................................................................................78
8.9.3 Troubleshooting ......................................................................................79
8.10 Fire alarm off ...........................................................................................79
8.10.1 Activate function......................................................................................80
8.10.2 Operating principle..................................................................................80
8.10.3 Troubleshooting ......................................................................................80
8.11 Smoke extraction ....................................................................................81
8.11.1 Activate function......................................................................................81
8.11.2 Operating principle..................................................................................81
8.11.3 Troubleshooting ......................................................................................82
9Logic.......................................................................................................83
9.1 Function ..................................................................................................83
9.2 Activate the logic.....................................................................................84
9.3 Assign texts.............................................................................................85
9.4 Setting values..........................................................................................85
9.4.1 Setting values switching value on and off...............................................85
9.4.2 Switch-on delay / switch-off delay...........................................................86
9.4.3 Minimum on-time.....................................................................................86
9.4.4 Minimum off-time.....................................................................................86
9.5 Operation selector...................................................................................86
9.6 Wiring test ...............................................................................................87
9.7 Priorities ..................................................................................................87
9.7.1 Notes.......................................................................................................87
9.8 Application examples ..............................................................................88
9.8.1 Application example storage tank charging ............................................88
9.8.2 Application example RS flip-flop .............................................................89
10 Function block: "faults" .......................................................................90
10.1 Purpose and activation ...........................................................................90
10.2 Fault priorities and acknowledgement ....................................................90
10.3 Universal fault inputs...............................................................................90
10.4 External fault button ................................................................................92
10.5 Fault relay ...............................................................................................92
10.6 Functional check / wiring test..................................................................94
11 Distribution zones.................................................................................95

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11.1 Overview .................................................................................................95
11.1.1 Direct application.....................................................................................95
11.1.2 Indirect application ..................................................................................96
11.1.3 Explanation example 2-pipe system .......................................................97
11.2 Function "Heat request" ..........................................................................97
11.2.1 Purpose and activation............................................................................97
11.2.2 Operating principle ..................................................................................98
11.3 Function block "Heat demand"................................................................99
11.3.1 Purpose...................................................................................................99
11.3.2 Heat demand relay..................................................................................99
11.3.3 Heat demand modulating ......................................................................100
11.3.4 Communication .....................................................................................101
11.3.5 Functional check / wiring test................................................................101
11.4 Function "Refrigeration request" ...........................................................101
11.4.1 Purpose and activation..........................................................................101
11.4.2 Operating principle ................................................................................101
11.5 "Refrigeration demand" function block..................................................103
11.5.1 Purpose.................................................................................................103
11.5.2 Refrigeration demand relay...................................................................103
11.5.3 Refrig demand modulating ....................................................................103
11.5.4 Communication .....................................................................................104
11.5.5 Functional check / wiring test................................................................104
11.6 Function block "H/C changeover" .........................................................105
11.6.1 Use and functions .................................................................................105
11.6.2 Activate function....................................................................................106
11.6.3 Preselected operating mode input H/C .................................................106
11.6.4 Operating principle ................................................................................107
11.6.5 Lock time ...............................................................................................108
11.6.6 Display current state .............................................................................108
11.6.7 Heating/cooling ch'over relay ................................................................109
11.6.8 Troubleshooting.....................................................................................109
12 Volume flow balancing VAV................................................................110
13 Communication ...................................................................................112
13.1 Activate communication ........................................................................112
13.2 "Communication" menu.........................................................................112
13.2.1 Factory settings.....................................................................................112
13.2.2 Room group 1...10 ................................................................................113
13.2.3 "Distribution zones" menu item .............................................................114
13.2.4 Universal transmission and reception zones ........................................114
14 RXB/RXL operation .............................................................................119
14.1 Operation of individual RXB/RXL room controllers ...............................119
14.2 Special features of setpoint readjustment .............................................120
15 Data acquisition...................................................................................121
15.1 Trend .....................................................................................................121
15.1.1 Connections and application.................................................................121
15.1.2 Views.....................................................................................................121
15.1.3 Trend function settings..........................................................................122
15.1.4 Troubleshooting.....................................................................................123
15.2 Meters ...................................................................................................123
15.2.1 Activate meters .....................................................................................124
15.2.2 Display format .......................................................................................124

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15.2.3 Pulse valency ........................................................................................124
15.2.4 Overflow value ......................................................................................124
15.2.5 Setting and resetting meter readings....................................................125
15.2.6 Display meter readings .........................................................................125
15.2.7 Assign texts...........................................................................................125
15.2.8 Troubleshooting ....................................................................................126
16 Device supervision .............................................................................127
16.1 Overview ...............................................................................................127
16.2 Activate function....................................................................................127
16.3 Create device list ..................................................................................127
16.4 Read device list.....................................................................................128
16.5 Fault status messages ..........................................................................129
17 Help in case of faults ..........................................................................130
17.1 Error/fault code list ................................................................................130
17.2 Troubleshooting ....................................................................................131
17.2.1 Fault indication......................................................................................131
17.2.2 Alarm acknowledgement.......................................................................132
17.2.3 Delete fault status messages................................................................132
17.3 Troubleshooting ....................................................................................133
18 Electrical connections........................................................................134
18.1 Connection rules ...................................................................................134
18.2 Connection terminals ............................................................................135
18.2.1 Central control unit RMB795B ..............................................................135
18.2.2 Universal modules RMZ785..................................................................135
18.2.3 Universal module RMZ787 ...................................................................135
19 Appendix..............................................................................................136
19.1 Abbreviations used ...............................................................................136
19.2 Configuration diagram...........................................................................136
19.2.1 Explanation of configuration principle ...................................................136
19.2.2 Overview of function blocks ..................................................................137
19.2.3 Configuration diagram RMB795B .........................................................140
19.3 C3127_Planning and commissioning protocol......................................141

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1 Overview
1.1 Central control unit RMB795B
The RMB795B is a central control and operator unit for room control in connection
with SyncoTM RXB/RXL and with room thermostats RDG/RDF/RDU. It significantly
extends the field of use of the SyncoTM system.
The room controller RXB/RXL and Synco room thermostats RDG/RDF/RDU are
referred to below as individual room controller.
Thanks to the KNX bus, the bus communication capability of the controller network
can be used in the easiest possible manner. For that, the typical easy-to-
understand SyncoTM operating concept has been maintained.
Whether for end-users, engineering, service or commissioning staff, menu-driven
operation in clear-text underlines the system’s user-friendliness at all levels.
The RMB795B central control unit is operated via a plug-in type or detached
operator unit.
The RMB795B central control unit facilitates central operation of room groups
equipped with RXB/RXL room controllers while offering the following features:
•Time switch, calendar and special day programs
•Preselected setpoints and trend functions
•Supervision of the highest / lowest temperatures and device supervision
•Collects and forward demand signals to the primary side
1.2 Product range
The table below shows the various comprehensive solutions for use with the
RMB795B and individual room controllers:
Room unit Illustration Name Type Data
Sheet
Switching and
control units
Central control
unit
RMB795B N3122
Room controlled
Room controller
RXB..
RXL
N3873
N3874
N3877
Room thermostat RDF N3171
What is the RMB795B
central control unit?
Note
KNX makes it possible
User-friendliness
at all levels
Function
Control units,
accessories

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Room thermostat RDG N3191
N3192
Room thermostat RDU N3172
Extension
modules
Universal module RMZ787 N3146
Universal module RMZ785 N3146
Module
connector
RMZ780 N3138
Operator units
Operator unit,
plug-in type
RMZ790 N3111
Operator unit,
detached
RMZ791 N3112
Type of room unit QAW740 N1633
Operator unit 1
Service tool OCI700.1 N5655

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1.3 Synco™ 700 topology
RMZ791 RMZ790
OCI700.1
RX..
OZW772...
RMS..
RMZ78..
RMZ792
Ethernet
Router
Internet
Web-Browser
RDG.. RDF/RDU
RMH..
RMU..
RMK..
RMU.. Universal controller RMK.. Boiler sequence
controller
RMZ790 Operator unit, plug-in type RMB795B Central control unit
RMZ791 Operator unit, detached RX.. Room controller
RMZ792 Bus operator unit RDG.. RDF.. RDU.. Room thermostat
RMZ78.. Extension modules OCI700.1 Service tool
RMS.. Switching and monitoring device OZW772.. Web server
RMH Heating controllers
1.4 Equipment combinations
The table below shows the types of devices that can be combined with the
RMB795 and the extension modules:
Room unit Type Data Sheet
Passive sensors All types of sensors with sensing
element
LG-Ni1000, Pt1000, T1 (PTC)
N1721...N1847,
N1713
Active sensors All types of sensors:
•operating on AC 24 V
•with modulating output DC 0...10
V
N1821,
N1850...N1962
Monitors QAF81..., QAF64...,
QFA81, QFM81,
QFA1000, QFA1001,
QFX21, QXA2000,
QBM81...
N1284, N1283,
N1513, N1514,
N1518,
N1541, N1542
N1552
Volume flow
controller VAV
G…B181.1E/3
G…B181.1E/KN networked versions
N3544
N3547
Use of RMB795B
central control unit
Key
Sensors and monitors

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1.5 Product documentation
In addition to this Basic Documentation, the product documents listed below
provide detailed information about the safe and correct deployment and operation
of Synco™ 700 products in building services plant.
Type of document Document no.
Range description: Synco™700 CE1N3110en
Basic documentation: Central control unit RMB795B CE1P3122en
Data sheet: Central control unit RMB795B CE1N3122en
Data sheet: Universal modules RMZ78.. CE1N3146en
Data sheet: Module connector RMZ780 CE1N3138en
Data sheet: KNX bus CE1N3127en
Basic documentation: Communication via KNX bus CE1P3127en
Installation instructions (G3151xx): RMB795, RMS705B, RMU7..B 74 319 0731 0
Mounting instructions (M3110xx): RMZ78.. 74 319 0353 0
Mounting instructions (M3112xx): RMZ791 74 319 0339 0
Declaration of Conformity (CE) HVAC Controls Synco 700 Range CE1T3110xx
Environmental declaration (RMU7..B, RMS705, RMB795,
RMH760, RMK770)
CE1E3110en01
Environmental declaration (RMZ78..) CE1E3110en02
Environmental declaration (RMZ790) CE1E3110en03
Environmental declaration (RMZ791) CE1E3110en04
Environmental declaration (RMZ792) CE1E3131en
1.6 Output
Summary of the functions and features for the central control unit RMB795B:
Outfit / functions RMB795B
Canned applications 1
Extension modules
Extension with 2 universal modules RMZ787
each with 4 universal inputs and 4 relay outputs
Extension with 1 universal module RMZ785
with 8 universal inputs
3
Room groups 10
Control of room operating mode per room group 
Via operator unit RMZ79x 
Via digital inputs (room operating mode selector switch
and timer function)

Via internal time switch (7-day time switch) 
Via room unit QAW740 
Via KNX bus (room operating mode selector switch and
timer function)

Control of calendar per room group 
Via operator unit RMZ79x 
Via digital inputs (for holidays/special days) 
Via KNX bus (for holidays/special days) 
Control functions per room group 
Fire alarm off. 
Smoke extraction supply air/extract air 
Night cooling. 
Free cooling 
Supplementary
information
Overview

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Outfit / functions RMB795B
Precooling 
Fan only 
Boost heating 
Emergency heating 
Off 
Room operating mode output per room group 
Setpoint per room group 
Summer/winter compensation. 
Setpoints (absolute) 
Setpoint readjustment via room unit QAW740 
Setpoint priority for RMB or room controller 
Highest / lowest temperature supervision per room group 
Alarms 
Free fault inputs (digital or analog) 10
Fault status signal relay. 2
Universal inputs (central control unit and extension modules) 22 (6 + 4 + 4 + 8)
As analog input DC 0...10 V. 
As analog input Ni 1000. 
As analog input Pt 1000 
As analog input T1. 
As digital input. 
Data acquisition
Online trend channels 4
Pulse counter 4
Switching outputs (relays) 12 (4 + 4 + 4)
Modulating outputs (analog) 2
Logic blocks 10
Heat demand signal Relays and modulating 
Refrigeration demand signal Relays and modulating 
H/C changeover of 2-pipe system 
Operation and observation of RXB/RXL room controllers 
Setpoints for room groups 
Monitoring devices 
1.7 Important notes
This symbol draws your attention to special safety notes and warnings. Failing to
observe these notes may result in injury and / or serious damage.
You may only use Synco™ 700 products to control and monitor heating, ventilation,
air conditioning and chilled water plants.
Safe and trouble-free operation of Synco™ 700 products presupposes transport,
storage, mounting, installation and commissioning as intended as well as careful
operation.
Fuses, switches, wiring and earthing must comply with local safety regulations for
electrical installations.
Only qualified staff trained by Siemens Building Technologies may preparte for
use and commission Synco™ 700 products.
Synco™ 700 products may only be operated by staff instructed by Siemens
Building Technologies or its delegates and who understand the potential risks.
Field of use
Intended use
Electrical installation
Commissioning
Operation

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When wiring the system, strictly segregate the AC 230 V section from the AC 24 V
safety extra-low voltage (SELV) section to ensure protection against electric shock
hazard!
For storage and transport, observe the limits from the relevant data sheets at all
times.
If in doubt, contact your supplier or Siemens Building Technologies.
Synco™ 700 products are maintenance-free and require only cleaning at regular
intervals. We recommend removing dust and dirt from system components
installed in the control panels during standard service.
If system faults occur and you are not authorized to perform diagnostics and rectify
faults, call your Siemens Building Technologies service representative.
Only authorized staff may perform diagnostics, remedy faults, and restart the plant.
This also applies to working within the panel (e.g. testing or changing fuses).
Do not dispose of devices with electrical and electronic components as part of
domestic waste.
Observe all local legislation.
Wiring
Storage and transport
Maintenance
Faults
Disposal

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2 Operation
Synco™ 700 devices may only be operated by staffs who has been instructed
by Siemens Building Technologies or their delegates and whose attention
has been drawn to potential risks.
2.1 Operation without operator unit
Without the operator unit, the following operating elements on the central control
unit RMB795B and extension module can be used:
3140Z02
1
234
3140Z03
5
Central control unit Extension module
The operating elements shown above have the following functions:
Ref. Operating element Function
1 LED Run Indication of the unit’s operating state:
LED lit: Power on, correct use and no fault in
the peripheral devices
LED off: No power or incorrect use / faulty
peripheral devices
2 Fault button
with LED (red)
Indication and acknowledgement of a fault status
message:
LED flashes: Fault status message ready for
acknowledgement
LED lit: Fault status message still present but
not yet reset
LED off: No fault status message present
Press button Acknowledge fault or reset.
3 Prog button Learning button for switching between normal mode
and addressing to adopt the physical device address
(tool required)
4 LED Prog LED to indicate "Normal mode" (LED off) or
"Addressing mode" (LED on); it extinguishes after
adoption of the physical address
5 LED Run Supervision of power supply and addressing:
LED lit: Power on, module addressing lit
LED flashes: Power on, but module not yet
addressed by the RMB795B central
control unit
LED off: No power
Operating elements
Functions

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2.2 Operation with operator unit
2.2.1 Operator unit functions
The operator unit is used to make all settings and readouts required for operating
the RMB795B central control unit.
All entries made on the operator unit are transmitted to the central control unit
where they are handled and stored. The operator unit itself does not store any
data. The information for the user is generated by the central control unit and
forwarded to the operator unit where it is displayed.
2.2.2 Operating concept
All setting and readout values are arranged as data points (operating lines) in a
software menu tree. Using the operating elements, any data point can be selected
and read or set. The LCD shows all menus in plain text..
The central control unit has several languages loaded. Enter the relevant language
during commissioning. The Operating Instructions for the end user are included
with the central control unit; they contain the languages with which the unit is
supplied.
The pictures below show the 2 types of operator units with their operating
elements:
3111Z07
2
1
5
3
4
Plug-in type operator
unit RMZ790.
3
4
2
5
1
3112Z08
Detached operator
unit RMZ791
The operating elements shown above have the following functions:
Ref. Operating element Function
1 Display Display of key plant data (info level)
2 INFO button Function 1: Display of key plant data
Function 2: Display of information about the individual
data points on the current menu
3 Press-and-select
knob OK
Turn: Selection of operating line and adjustment
of value
Press: Confirmation of operating line or setting.
4 ESC button Going back to the previous menu
5 Fault button
with LED (red)
LED: Indicates a fault.
Press: Acknowledge fault or reset.
Brief description
Basics
Operating elements
Functions

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When one of the operating elements is activated, the backlit display will
automatically be switched on. It switches off and the start page appears when
inactive for 30 minutes.
The pictures below show a number of typical displays, including explanations:
Display Explanation
Wednesday 22.12.04 14:52
Welcome
Information
Main menu »
Start page
Main menu
Room group 1...
Inputs...
Time/date...
Faults...
Setting level
Selection of a setting parameter,
e.g. on the main menu of the user level.
Entry 1
Start: ––.––.–– ––.––
End: ––.––.–– ––.––
Reason: Holidays.
Delete entry...
Setting level
Pop-up, setting a numerical value
Main menu> Controller 1
Room operating mode…
568
Setting level, INFO button pressed:
Help picture with explanations relating to the
selected setting parameter (as long as INFO
button is kept depressed).
Note:
When on the access levels "Service" and
"Password", the number in the bottom right-hand
corner is the text ID number of the menu or
setting parameter.
Room group 1...
Operating mode: Comf
Cooling setpoint: 24.0 °C
Heating setpoint: 21.0 °C
Cause: Time switch
Info level
Here, for example, info page RG1 (room
group 1), after pressing the INFO button and
selecting Display of key plant data.
Note:
When turning the knob, the other info pages can
be retrieved, e.g. the time programs of the
relevant room group.
The names of the submenus Room group 1…10 and Trend channel 1…4 are
factory settings. They can be replaced by the service engineer during
commissioning by using project-related clear-text names.
If, later, with the respective menu lines, the INFO button is pressed, the original
default text will reappear.
Backlit display
Display examples
Note
25.02

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Siemens Central control unit RMB795B CE1P3122en
Building Technologies Operation 18.01.2012
2.2.3 Operating levels
There are 2 operating levels:
•Info level
•Setting level
These 2 levels are always available, no matter which access level is active.
Important plant data can be queried in this level.
The setting level is arranged in the form of a menu structure. It provides for reading
and adjustment of data points.
Using the INFO button, explanations relating to the menus with the individual data
points can be displayed. The information is displayed as long as the button is kept
depressed.
Switching from the info level to the setting level:
1. Select the start page by pressing the ESC button.
2. Press the OK knob to change to the setting level.
Switching from the setting level to the info level:
1. Select the start page with the ESC button. Press the button repeatedly until the
start page reappears.
2. Press the INFO button to change to the info level.
2.2.4 Access levels
The RMB795B central control unit has 3 access levels. An access right is defined
for each parameter (operating line).
Level Access Symbol
User level (for the
plant operator)
The user level can be accessed any time.
Users can modify all data points that are
visible/adjustable at this level.
Service level
(for maintenance)
Press the OK knob and the ESC button
simultaneously. Then, select operating line Service
level and confirm by pressing the OK knob.
Password level
(for
commissioning)
Press the OK knob and the ESC button
simultaneously; then select operating line Password
level and confirm by pressing the OK knob.
Then, enter number 7as the password and confirm
by pressing the OK knob.
•The access level determines which individual menus and operating lines are
activated.
•A higher access level also shows the menus and operating lines for the lower
access levels
•The levels use a shared menu as a basis The password level displays the entire
menu tree
•After a time-out, the central control unit changes to the user level.
Time-out: If the central control unit is not operated for 30 minutes
Two operating levels
Info level
Setting level
Switching between the
operating levels
3 access levels
Common properties

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Siemens Central control unit RMB795B CE1P3122en
Building Technologies Operation 18.01.2012
Switching from the current access level to some other access level:
1. Press the OK knob and the ESC button simultaneously:
The Access levels menu is displayed.
2. Select the required access level by turning the OK knob and confirm by
pressing the knob.
3. Enter number 7to access the password level.
Changing the
access level