Siemens AS 235, AS 235 H, AS 235 K User Manual

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TELEPERM M

AS 235, AS 235 H and

AS 235 K

Automation Systems

Catalog PLT 111 · 1999

This catalog is no longer available in printed form. However, it can still be used to obtain information and for ordering spare parts.

Certain products from this catalog are no longer available. Your Siemens partner will offer appropriate substitutes wherever possible.

The products and systems described in this catalog are marketed under application of the quality management system certified by DQS in accordance with DIN EN ISO 9001 (certificate register No.: 2613-04). The

DQS certificate is recognized in all EQ Net countries (Reg. No.: 2613).

Introduction

System architecture

Automation systems

I/O modules

Input and output devices

Bus communication

Coupling with other systems

Appendix

REG. NO. 2613-04

This catalog is out of date, see note on page 1

TELEPERM M

Introduction

Brief description

TELEPERM M process control system

Engineering

The TELEPERM M process control system provides all functions required for process automation. It is highly suitable for the complete automation of continuous and discontinuous (batch) processes.

The TELEPERM M systems are divided into function units optimized for different tasks associated with process automation:

•AS automation systems

•OS operator systems

•CS and PROFIBUS bus systems

AS automation systems

The various TELEPERM M automation systems have different designs, ranges of functions and performances. The AS 235, AS 235 H and AS 235 K automation systems described in this catalog are proven and reliable. They can be configured within wide limits and coupled to a wide range of subordinate systems. The AS 235 H additionally has a redundant central unit and thus satisfies particularly high availability demands. The AS 235 systems can communicate with one another and with higher-level systems via the TELEPERM M CS 275 plant bus.

A wide range of TELEPERM M input/output modules is available for connection of the process peripherals (sensors and final control elements) to the AS 235, AS 235 H and AS 235 K automation systems. Some modules have their own processing features or can be configured application-specific.

The AS 388/TM and AS 488/TM automation systems (see Catalog PLT 112) use the SIMATIC M7-300 and M7-400 automation computers as the hardware platform and are compatible with the AS 235 system. They are appropriate for the extension of existing TELEPERM M systems or for the design of new systems.

The AS 388/TM and AS 488/TM systems can be operated on the PROFIBUS-TM plant bus. PROFIBUS-TM is based on the standardized PROFIBUS. The AS 488/TM system can additionally be operated on the CS 275 plant bus.

ET 200M distributed I/O systems with a comprehensive range of I/O modules can be connected to the AS 388/TM and AS 488/TM systems via one or two PROFIBUS-DP interfaces.

OS operator systems

The bus-compatible OS 525 (Catalog PLT 122) and WinCC/TMOS (Catalog PLT 123) operator systems are used for process communication. They communicate with the subordinate TELEPERM M automation systems and with SIMATIC S5-155U via the CS 275 plant bus or PROFIBUS-TM.

The operator systems can have a configuration variable from a single-user system up to a multi-user system - where the OS basic unit communicates with several terminals via a terminal bus - and can thus cover the complete range from low-end to high-end applications.

The OS 525 Local system permits the design of a local AS operating console with the complete range of OS 525 functions.

The PROGRAF AS+ configuring software is used for the AS 235, AS 235 H, AS 235 K, AS 388/TM and AS 488/TM automation systems and offers a wide range of support for documentation and configuring by means of a graphic functional diagram editor and an integrated database, amongst others.

Any single-user system WinCC/TM-OS-Single with RC license (Runtime+Configuration) is suitable as the configuring system for WinCC/TM-OS, and an OS 525 single-user system/terminal with OS 525-BIPRO configuring software for OS 525.

Plant bus

The plant bus is the central communication component of every distributed process control system. Two different bus systems are available for the TELEPERM M process control system, and can also be combined together within a system:

•CS 275

•PROFIBUS-TM

The CS 275 plant bus which has been proven in many automation plants is predestined for communication between the

AS 235, AS 235 H, AS 235 K and AS 488/TM automation systems and the OS 525 and WinCC/TM-OS operator systems. The CS 275 plant bus functions according to the token passing principle and can also have a redundant configuration. Several buses can be combined together using bus couplers such that bus networks are produced corresponding to the plant structure. The bus system is provided with distributed control. The bus interface of each subsystem may take over the master function according to specific criteria.

The AS 388/TM and AS 488/TM automation systems and the OS 525 and WinCC/TM-OS operator systems can be connected to the PROFIBUS-TM plant bus. The PROFIBUS-TM is characterized in that it complies with the modern PROFIBUS communication standards to EN 50170 but also uses the TELEPERM M communication mechanisms of the CS 275 (AKS, BKS, MKS and PL/PS telegrams) at the user level (link between bus interface and application).

The PROFIBUS-TM plant bus also operates according to the token passing principle. It can be designed as an electrical or optical network. The two network instructions can also be mixed together. PROFIBUS-TM is preferably used for new systems or partial systems.

The CS 275 and PROFIBUS-TM buses can be connected together by a CS-L2 bridge, thus permitting linking of existing systems and new systems.

Note:

Information systems, computers from other manufacturers, personal computers and gateways can be connected to the CS 275 plant bus. Personal computers with the Win TM software package can also be connected to PROFIBUS-TM.

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TELEPERM M

Introduction

Brief description

WinCC/TM-OS

SIMATIC PCS 7

operator

terminals

	Terminal bus
WinCC/TM-	PROGRAF AS+	WinCC/TM-	OS server
OS server	configuring	OS server	SIMATIC
incl. WinCC/TM-CS 275	software	incl. WinCC/TM-	PCS 7
incl. WinCC/TM-CS 275		incl. WinCC/TM-	PCS 7
	Bridge	PROFIBUS
CS 275	Bridge
CS 275			PROFIBUS-TM

AS 235		AS
		488/TM
	DP	ET 200M
	-
I/O modules	PROFIBUS
TELEPERM M

AS	AS	AS 414/
488/TM	388/TM	AS 416 / AS 417

-DP	-DP	-DP
PROFIBUS	PROFIBUS	PROFIBUS	TELEPERM M
			I/O modules


TELEPERM M			SIMATIC PCS 7

Fig. 1/1 System configuration for the TELEPERM M process control system, with migration to the SIMATIC PCS 7 process control system

Functions of the AS 235 system

The AS 235, AS 235 H and AS 235 K automation systems provide all I & C functions such as measurement, supervision, calculation, closed-loop control and open-loop control, also particularly taking into account batch processes. The automation systems also handle the tasks for local operation and monitoring, e.g. display, signalling, alarm output, process operation and logging.

The AS 235 and AS 235 K only differ in their design. The AS 235 system is fitted in a cabinet, the AS 235 K system in a wall housing. The AS 235 H system with a redundant central unit is provided for applications with particularly high availability demands.

A large range of dedicated function blocks is available for solving I & C tasks in the AS 235, AS 235 H and AS 235 K automation systems. “Programming” of the automation systems is thus made extremely simple since the function blocks present in the system memory need only be activated by entering configuring instructions and parameters.

In addition, the AS 235, AS 235 H and AS 235 K permit the use of additional languages for special tasks - such as optimization, startup and shutdown of open-loop controls - which are difficult to solve using the existing function blocks or the batch functions. The TML process language (TELEPERM M Language) is available for analog and binary processing operations, as well as the STEP M control language already known from the SIMATIC industrial automation system. TML/STEP M can be used to define new function blocks optimally tailored to the respective task. Despite an extremely high degree of freedom, the clear and transparent “Block technology” is not relinquished. Frequently occurring block combinations can be combined into socalled Typicals and can then be used just like a single block.

A wide range of input and output modules is available for the AS 235, AS 235 H and AS 235 K systems as the interface to the process.

Intelligent I/O modules, e.g. modules which can carry out closed-loop control functions on their own, make it possible to configure a subordinate individual single-loop control level. This increases the availability of the automation system even further.

Further to this, the process interface is supplemented in particular for power applications or distributed small systems by sys- tem-compatible coupling of SIMATIC components.

The AS 235, AS 235 H and AS 235 K systems have either one or two autonomous operation channels for local operation and monitoring. This means that the process operation keyboard, process monitor and printer can be connected to each of the two operation channels and carry out operation and monitoring functions independent of one another.

In addition to the standardized displays which are achieved by addressing the automation function blocks without carrying out any further configuring, the user can also configure free displays. A standardized display is e.g. the loop display for operation of a control loop, a free display is the schematic representation of plant components (flowcharts) in their respective process status.

The local operation devices may be omitted when using central operation and monitoring in a network configuration.

Configuring

Configuring includes the incorporation of the automation structure into the automation system by using configuring instructions, by specifying parameters, by programming with TML and STEP M if applicable, and the feedback documentation.

This is possible either without an additional programming device/personal computer directly on the automation system (direct configuring, input/output using lists) or by using a PROGRAF AS+ engineering tool on a programming device/PC. Both configuring methods can be used

•locally for one automation system or

•centrally from one AS 235 system or one PC with PROGRAF AS+ for bus-coupled systems.

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TELEPERM M

Introduction

System data

General system data 1)

Permissible ambient temperature

• Modules		0 to 70 °C
– Operation
–	t/h	Max. 10 K
–	t/min	Max. 0,5 K
– Transport and storage		-40 to +70 °C
• Cabinet (operation)
Cabinet ambient temperature at
1 m above cabinet base		0 to 40 °C
Reduction in specified temperature		10 K/1000 m
above 1000 m above sea level
Permissible humidity		Operation	Storage
– Annual average		Max. 75 %	Max. 65 %
– On 30 days/year		Max. 95 %	–
– On 60 days/year		–	Max. 85 %
Condensation not permissible
Mechanical ambient conditions
Operation stress

(modules in subrack)
– 10 to 60 Hz		0.15 mm deflection
– 60 to 500 Hz		2 g acceleration
System cabinet
– 10 to 58 Hz		0.035 mm deflection
– 58 to 500 Hz		0.5 g acceleration
Transport stress

(modules in subrack)
– 5 to 8 Hz		7.5 mm deflection
– 8 to 500 Hz		2 g acceleration
Design, earthing conditions
Potential difference between all		Max. 7 V
ground star points of distributed
systems
Insulation		According to VDE 0160
Protection class		Class l
Insulation of modules, clearances and		According to VDE 0110
creepage distances from pin to pin or
from conductor to conductor
Signal data
(interface to field level)
• Binary signals
DC voltage		Referred to M potential
Signal definition
		Inputs	Outputs
– L (low)		-30 to +4.5 V	0 to 2.5 V
– H (high)		+13 to +33 V	L+ to
			(L+ - 2.5 V)
Input currents
– Electronic transmitters		0.5 mA	Typical values for
– Contacts		4 mA	configuring
Output currents with DC 24 V		8.5 mA/100 mA/120 mA
Power signals		Max. 400 mA
Binary signal outputs		Short-circuit-proof and
		overload-proof

General system data

• Analog signals
DC voltage	Referred to MZ
– Rated range of use	-10 to +10 V
	-10 to 0 V
	0 to +10 V
– Overflow range
– Overflow range	-10.5 to +10.5 V
– Input resistance	100 kΩ
– Output loading capacity	1 mA
Direct current	Referred to M
– Rated range of use	0 to 20 mA or 4 to 20 mA
– Overflow range	0 to 21 mA or 3.7 to 21 mA
– Input resistance	12.5, 50 or 350 Ω
– Rated output load	500 or 600 Ω
Analog signal outputs
Analog signal outputs	Short-circuit-proof and over-
	load-proof
Overvoltage resistance of binary and	Class II
analog inputs and outputs according
to IEC information 255-4 (Fig. 1/2)

Fig. 1/2 Overvoltage resistance / dynamic destruction limit

1)Deviations possible in individual cases. Refer to technical data of individual components

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TELEPERM M

Introduction

System data

Technical data of automation systems

Technical data of automation systems (continued)

Central unit
Central processor	Microprogrammed
Arithmetic unit processing width	32 bit
Process execution levels	5
• Acyclic	2 (alarm and background levels)
• Cyclic
• Cyclic	2 (125 ms, 1 s) and communica-
	tion level

Memory (EDC)	1-bit correction when reading
Interface to central processor	16 bit wide
Main memory (RAM)	4000 kbyte
Memory for system software (RAM)	1 Mbyte
Memory backup time (RAM) Tmin	480 h

Input and output devices

Operation unit

•Number of operation units which can be used simultaneously

Process monitor

•Vertical frequency

•Horizontal frequency

•Video signals

Graphic display

•Semi-graphics

•Format

•Colors

•Resolution

•Message line

•Working field

•Input line

Configuring unit

Mini floppy disk unit

•Diskette format

•Max. storage volume per diskette

Logging printer/message printer

•Number of logging/message printers which can be operated simultaneously

•Format

•Printing speed with normal font

1 process monitor

1 process operation keyboard

50 Hz non-interlaced

15.625 kHz

RGB with SYNC in green channel

32 lines with 64 characters each

High-resolution

29 lines

1, for configuring

1 configuring keyboard,

1 mini floppy disk unit

5.25 inch

1 Mbyte

Needle and ink-jet printers

2 / 2

DIN A4 (80 characters/line) or DIN A3 (136 characters/line)

300 characters/s

Power supply for AS

Supply voltage

•Redundant supply

•Permissible range including ripple

Permissible ripple (DC 24 V systems)

Limiting range of use (DC 24 V systems)

Voltage dip with UN=24 V (DC 24 V systems)

External fusing required

Current consumption of basic unit/ basic system (typical value without I/O modules)

Power consumption (basic unit/system)

Permissible thermal load in cabinet (for AS 235 and AS 235 H)

•Without heat exchanger 1)

–Without fan subassembly

–With fan subassemblies

•With heat exchanger and fan subassemblies

Heat to be dissipated from housing (only AS 235 K)

Degree of protection EN 60 529

•Standard cabinet without heat exchanger

•Standard cabinet with heat exchanger

•Sheet-steel housing

•Subrack

Impairment of function by gases

DC 24 V

(AS 235 K also

AC 50/60 Hz, 230 V)

With AS 235 H and AS 235 K, DC 24 V; as option with AS 235

DC 20.8 to 33 V (AS 235 and AS 235 K, DC 24 V)

DC 21.6 to 31 V (AS 235 H)

15 % of mean DC value within the permissible range

35 V ≤ 500 ms

45 V ≤ 10 ms

0 V ≤ 5 ms, recovery time 10 s

–Max. 80 A with I/O modules (AS 235 and AS 235 H)

–25 A (AS 235 K, DC 24 V)

–10 A (AS 235 K, AC 230 V)

5.5 A (AS 235)

8.5 A (AS 235 H)

6.5 A (AS 235 K, DC 24 V)

1.0 A (AS 235 K, AC 230 V)

–Max. 160 W (AS 235, without I/O modules)

–Max. 200 W (AS 235 H, without I/O modules)

–Max. 220 W (AS 235 K, DC 24 V, with I/O modules)

–Max. 330 VA (AS 235 K,

AC 230 V, with I/O modules)

Max. 350 W

Max. 700 W

Max. 1000 W

Max. 200 W
AS 235/235 H	AS 235 K
IP 20	–
IP 54	–
–	IP 21
IP 00	IP 00

Industrial atmospheres for occupied rooms are permissible

1) With cabinet inlet temperature 40 °C

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TELEPERM M

Introduction

System data

Technical data of automation systems (continued)

I/O modules
Function modules/calculation mod-	Autonomous closed-loop and
ules	individual control drive modules
	or user-configured with own
	microprocessor
Signal modules
Signal modules	Binary and analog
Counter modules	Metered pulse module, pro-
	portioning counter module
Coupling modules	For SIMATIC S5/S7 peripheral
	I/O modules and devices, and
	for subordinate devices and sys-
	tems
Max. number of I/O modules	90 / 1141)	(AS 235)
	91 / 1031)	(AS 235 H)
	6 / 1081)	(AS 235 K)

Typical quantity breakdown
Control loops	30 to 80
Additional analog-value monitoring	50 to 120
Sequential controls	5 to 15
Logic controls	100 to 250
Any number of flowcharts (up to 8
colors) and individually formatted
logs
Dimensions / weight
Dimensions (H x W x D) in mm
• Standard cabinets
• Standard cabinets
– With degree of protection IP 20	2200 x 900 x 400
– With degree of protection IP 20	2200 x 900 x 600
and IP 54
• Housing with degree of protection	820 x 600 x 360
IP 21
Weight
• AS 235 / AS 235 H	200 to 250 kg 2)
• AS 235 K (DC)	77 kg 3)
AS 235 K (AC)	85 kg 3)

1)When used with ES 100 K extension system

2)Typical value, depends on configuration with I/O modules

3)Without I/O modules

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System architecture

	2/2	Performance characteristics
	2/4	Redundancy with AS 235 H
Configuring
	2/5	Standard function blocks
	2/10	User function blocks

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System architecture

Performance characteristics

The AS 235, AS 235 H and AS 235 K systems are programmable automation systems of the TELEPERM M process control system based on function blocks. They have a different design and availability, but the same range of functions. The AS 235 K system is fitted in a wall housing, the AS 235 and AS 235 H systems are fitted in cabinets. The AS 235 H automation system has a redundant central unit to satisfy particularly high demands placed on the availability.

The systems can either be used on their own with local operation and monitoring, or coupled in system networks with central operation and monitoring.

System configuration

The automation systems consist of:

•A basic unit (AS 235, AS 235 H) or a basic system (AS 235 K)

•ES 100 K extension systems (wall housing) or extension units (for fitting in cabinets) as extension for configuring with input/ output modules.

Standard input/output devices enable local communication with the automation system during the configuring and commissioning phases as well as during later operation. The following can be connected:

•54-cm (21-inch) process monitors

•Process operation keyboard and configuring keyboard, max. 2 of each for 2 independent operating consoles

•Max. 4 logging printers

•1 mini floppy disk unit for booting the system memory and for loading/saving the user memory.

Basic system/basic unit

The basic unit (AS 235, AS 235 H) or the basic system (AS 235 K) mainly contains

• the power supply modules,

I/O modules

There are the following groups of I/O modules:

•Signal modules

•Function modules

•Calculation modules

•Coupling modules.

Signal modules are required for input and output of the process signals, usually without further processing (exception: adaptation of characteristic with temperature measurements).

Function modules (closed-loop control modules) and calculation modules have additional performance features which are independent of the central unit of the automation system and which can be used to increase the total processing performance or the availability by transferring backup functions should the central unit of the automation system fail.

The calculation modules enable the configuring of individual user functions.

Coupling modules enable the connection of I/O modules over larger distances. They additionally enable use of non-intelligent I/O modules of the SIMATIC S5 programmable controllers, plus the ET 100U distributed I/Os for the automation systems.

Memory, configuring

The memory with battery backup of the automation systems is divided into:

•a system memory and

•a user memory.

The write-protected system memory contains the software which always belongs to the automation system, in the form of basic programs and function blocks. Far more than 100 standardized blocks are available for data acquisition, closed-loop control, open-loop control, calculation, supervision, logging, display and operation/monitoring.

•the central processor module,

•a memory module with user memory with 4,000 Kbyte capacity and battery backup and

•the interface modules for the input and output devices and the CS 275 bus system,

each of which is redundant in the AS 235 H system.

The central processor is microprogrammed and has a maximum processing width of 32 bits. Three basic cycles are present for processing (125 ms, 1 s and background level). An acyclic mode can also be defined.

The basic unit of the AS 235 and the basic system of the

AS 235 K each has 6 slots for I/O modules. No I/O modules can be plugged into the basic unit of the AS 235 H systems.

The following can be fitted into the systems as standard:

• AS 235	Max. 90	I/O modules
	(basic unit + 6 extension units)
• AS 235	H Max. 91	I/O modules
	(7 extension units)
• AS 235	K Max. 108 I/O modules

(basic system + eight ES 100 K extension systems)

Instead of programming the system with individual commands and carrying out the required program tests, it is only necessary in the TELEPERM M process control system to configure these complete function blocks in order to obtain a “user program”. In the simplest case, configuring means calling the function blocks with the keyboard, several times if necessary, and then assigning the respective linking instructions and parameters. The resulting application-oriented configuring data are then stored in the user memory.

Configuring is possible before the automation system is started up as well as during operation. It is possible to temporarily switch partial functions of the user system out of operation for this purpose.

Convenient configuring using graphic inputs is possible using the PROGRAF AS+ engineering tool which can be executed in a personal computer connected locally to the AS 235/235 H/235 K automation system or centrally to the CS 275 bus system.

The number of usable I/O slots with the AS 235 and AS 235 H can be increased by additional use of ES 100 K extension systems:

•AS 235 Max. 114 I/O modules

•AS 235 H Max. 103 I/O modules

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System architecture

STEP M

In addition to the function blocks for binary processing, the AS 235/235 H/235 K systems can use the STEP M control lan-

guage, without leaving the block configuration, in order to formulate extensive and complex open-loop control tasks.

TML language

The TML process language can be used in addition to the firmware blocks for special tasks. It can be used to format special function blocks and to implement particularly complex functions, e.g. for the mixing of binary value arithmetic and measured value arithmetic.

Operation and monitoring

The AS 235, AS 235 H and AS 235 K systems have either one or two autonomous operation channels for local operation and monitoring. This means that process operation keyboards, printers and process monitors can be connected in duplicate and operated using operation/monitoring functions which are independent of one another. Some of the local operation devices can be omitted in the case of central operation and monitoring with a network configuration.

Scope of performance

The user RAM of the automation systems has a memory capacity of 4,000 Kbytes. This means that even one single system can already implement larger automation tasks. Even the data quantities encountered with extensive batch processes can be handled. If it is taken into account that various tasks occur mixed together, the performance is approximately as follows:

•30 to 80 control loops

•50 to 120 additional analog-value monitoring functions

•5 to 15 sequential controls

•100 to 250 logic controls

•Any number of flow charts (up to 8 colors) and individually designed logs.

Performance characteristics

Summary of system properties

•Automation system for autonomous operation with local communication or for network operation with central communication

•Fitted in wall housing or cabinet

•Configurable within wide limits

(up to 114 I/O modules depending on system)

•User memory up to 4,000 Kbytes on one module

•32-bit processing of analog values

•Optimized data transfer rate resulting from separate processing of analog and binary values

•Central unit redundant as option with synchronous processing of clocks (AS 235 H)

•Operation without fans possible

•Complete range of standard function blocks

•User function blocks with convenient TML programming language, also STEP M programming language for open-loop control tasks

•Configuring/programming either online without programmer (using lists) or with PC (using graphics)

•Local or central configuring (via bus)

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System architecture

Redundancy with AS 235 H

CS 275

plant bus

Central

Synchronization

Central

processing

unit I

unit II

Comparison,

cross-coupling

Redundant I/O bus

Comparison,

switchover

I/O bus

I/O

modules

Process level

Redundant path

Fig. 2/1 1-out-of-2 redundancy structure with AS 235 H

Redundancy with the AS 235 H automation system

Various system characteristics must be considered with regard to the reliability and availability of a system. The requirements for reliability are met by fault-tolerant (high-availability) systems while those for safety are met by fail-safe systems.

According to VDI/VDE 3542 the following applies:

A system is fault-tolerant if occurring faults have no effect on its function. Fail-safe is the ability of a technical system to remain in a safe mode or to switch immediately to another safe mode in the event of a fault.

The AS 235 H automation system is a high-availability system with redundant central units operating with system clocks where execution of the planned automation functions is not interrupted by system faults.

The system operates according to the fault-tolerant 1-out-of-2 principle. The AS 235 H system is equipped with 2 identical central processing units for this purpose, the master unit and the slave unit (Fig. 2/1). Each of the two CPUs contains a power supply module, central processor, memory module for system software and user program as well as 1 or 2 interface modules for the I/O bus depending on the number of I/O modules connected. The user programs stored in the 2 memory modules are identical.

Process signals are always applied to both CPUs. Only one of these, the master unit, can output commands to the process via the I/O modules. The other operates in hot standby mode and is always able to take over smooth control of the process should the master unit fail.

The fully-synchronous mode of operation of the two partial

AS 235 H systems means that any assignment of the master is possible: master/slave or slave/master. Both partial systems are updated with the same information simultaneously because all input data are applied to both, meaning that online backup data transmission between the two partial systems is superfluous.

Central faults are detected very rapidly using a hardware comparator. This compares the redundant bus signals for each read or write operation of the central processors operating with synchronous clocks. Software test programs are started in the event of a fault in order to established its location.

The synchronous signals of the redundant I/O bus are checked for equality for selective areas of up to 13 I/O modules each and converted to the single-channel I/O bus of the standard I/O modules. Up to 3 selected I/O module areas can be supplied by the redundant I/O bus (A), a further 4 selected I/O module areas can be supplied by extending with a redundant I/O bus 2 (B). A strict division into fault limiting regions thus ensures that single faults can only have an effect within one selective I/O module area.

The AS 235 H system enables maintenance and repair without interfering with process operations. The corresponding partial system, irrespective of whether it is the master or slave, is removed from the synchronous operation. The partner system then retains the master status, or is assigned it automatically, and thus handles the active process operations. The disabled, passive partial system now operates completely independently, but without the I/O modules since these are required by the master.

This simplex operation with 2 independent systems enables new user programs to be configured, loaded or tested and to operate on the process either on a trial basis or permanently. This flexibility prevents undesirable down times in the process when changing the automation structure.

The backup of a passive partial system (transition from simplex to duplex operation with a slave system ready for operation) is initiated by the operator and is executed without influencing the online processing of the master system. It is terminated by automatic synchronization. The second partial system is then the slave and is ready to accept the master status at any time.

When connected to the CS 275 bus system, the redundant AS 235 H system responds like a single participant.

The user software of the AS 235 H automation system is compatible with that of the AS 235 and AS 235 K systems, i.e. user configurations which have been generated on these systems and which function directly can also be used in the AS 235 H system without limitations.

Important note:

The AS 235 automation system has been optimized for high reliability and availability by means of fault tolerance and a non-interacting design. However, it does not belong – just like any other single or redundant programmable system – to the class of special fail-safe systems approved by independent testing authorities (e.g. TÜV).

It is therefore important when automating processes or process sections relevant to safety to ensure that suitable subordinate interlocking circuits or protective systems are provided for these areas in the AS 235 H system as in the

AS 235 / AS 235 K systems which make a dangerous operating state impossible should faults occur in the automation system.

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System architecture

Configuring

Standard function blocks

Blocks for binary processing

Dedicated function blocks are present in the automation systems to solve the control tasks. These are the so-called standard function blocks. The AS 235, AS 235 H and AS 235 K systems have the same standard function blocks for data acquisition, closed-loop and open-loop control, calculation and monitoring.

The standard function blocks present in the system software are activated by engineering tools using configuring instructions. The blocks are combined into an automation structure which is processed cyclically, and sometimes acyclically, by the central processor of the automation system.

The configuration of the automation structure is usually generated graphically using the PROGRAF AS+ configuring tool (see also page 2/9).

The following tables list the standard function blocks divided according to their areas of application.

Blocks for analog and digital processing

Type	Designation	Function
SUM	Adder	Y = X1 + X2 - X3 - X4
MUL	Multiplier	Y = X1 · X2
DIV	Divider	Y = X1/X2

RAD	Square-root extractor	Y =	X or Y = K X
LN	Logarithm extractor	Y = KF · Ioge \| X \|
EXP	Exponential value	Y = ex
ABS	Absolute value	X = \| X \|

INT	Integrator	Y = K · X dt, K = 1/T
DIF	Differentiator	Y(s)/X(s) = (T·s)/(1 + (T·s/v))
PT
PT	Delay	Y(s)/X(s) = 1/(1 + T·s)
TOZ	Dead time	Y(s)/X(s) = e-s·T
MIN	Minimum-value	Y = minimum of X1, X2, X3
	selector
MAX	Maximum-value	Y = maximum of X1, X2, X3
	selector
TOB	Dead band	Y = X-TOBU for X < TOBU
		0	for TOBU ≤X ≤TOBO
		X-TOBO for X > TOBO
PLG	Function generator	Linear interpolation between 6
		pairs of turning points
GW	Limit monitor	Limit check between two switch-
		ing points
ASL	Analog-value switch	Y = X1 for S = “0”
		Y = X2 for S = “1”
SPEI	Analog-value mem-	Storage of up to 256 analog val-
	ory	ues

Type	Designation	Function
VU	AND	A = E1 E2 E3
VO	OR	A = E1 E2 E3
VN	Negation	A =
			E
VM	Flag	Flag of binary input signals (flip-
		flop)
VZ	Time delay	Switch-on and switch-off delays
VS + STEP	STEP M block	Freely programmable in STEP M
MPX	Multiplexer	To supply the STEP commands in
		the following VS/KS block
BW	Binary selection	Selection of status combination
		from up to 3 binary signals
INKU	Incremental con-	Converts analog value into an
	verter	open or close pulse
BCE	BCD input	Conversion of a BCD signal into
		an analog value
BCA	BCD output	Conversion of an analog value
		into a BCD signal
KA	Sequence start	Marks the start of an ON/OFF
		branch of a subgroup control
KAK		As KA, but with additional func-
		tions

KB	Sequence	Conditions of a control step, for
		power plants
KBK		As KB, but with additional func-
		tions
KS	Sequence step	As KB, for process plants
KV
	Sequence branch	Branch of a sequence into a max-
		imum of 6 branches, with process
		plants
KE	Sequence end	Last block in a sequence
KEK		As KE, but with additional func-
		tions
HA	Auxiliary oil auto-	Controls electric auxiliary oil
	matic unit	pumps for oil supply to generator
		sets
HUP	Horn block	Triggers signalling equipment
		(optical and audible)
EAR	Individual analog-	Allocates analog values from out-
	value allocation	puts in GA blocks
EBR	Single-bit allocation	Links individual binary outputs to
		GB/GM data blocks
UBR	Universal binary	Links 16 binary outputs to GB/
	location	GM data blocks

Siemens PLT 111 · 1999

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System architecture

Configuring

Standard function blocks

Blocks for processing with standardized operation and monitoring

Type

Designation

Function

RClosed-loop controlPID control, e.g. for disturbance

	ler	variable feedforward, tracking of
		setpoint and manipulated vari-
		able, limit formation
RN		As R,
		with additional functions

M	Measured-value	Monitors a measured value for 3
	monitoring	pairs of limits
		Extension of a closed-loop con-
		trol block for limit monitoring
		Limitation of measured value at
		the error limits
V	Ratio	Generation of a ratio, e.g. with a
		ratio control
		Proportional adjuster, e.g. with
		synchronization control or to influ-
		ence the command variable in a
		cascade
B
B	Operation block	Display of analog values (internal
		result of calculations, ...)
		Access to analog and binary val-
		ues (input of constants, ...)
S	Control unit	Operation and monitoring of a
		sequence in process plants
G	Subgroup control	Operation and monitoring of
		sequences in power plants
GK	Group control	As G,
GK		with additional functions
A	Output for binary	Display of and access to a binary
	data	value
F	Window block	Display of 5 measured values;
		each of the 5 values is monitored
		for a pair of limits
FN	Window block	Display and limit monitoring of 5
		measured values;
		input of 5 pairs of limits each with
		hysteresis as well as 5 ranges for
		the measured value display
T	Trend 1)	Display of the trend of 2 mea-
		sured values as a bargraph; time
		base between 1.625 s and 36 h
SR	Recorder 1)	Summary of up to 4 series of
		measurements, displayed on
		screen as dashed-line curves;
		4 pairs of limits for monitoring the
		measured values
C	Selector	To switch over binary signals,
		e.g. manual/automatic mode
PKM	Alarm acquisition	Acquires planned alarms from
		binary input module/GB block
PKF	Alarm sequence dis-	Output of PKM alarms; new
	play 1)	alarms of PKM blocks, display of
		alarm history

1) Displays in PROGRAF AS+

Data blocks

Type	Designation	Function
GA	Data block for global	Storage of 256 analog values
	analog values	with error 10-9;
		storage of process image, histor-
		ical values etc.
GB	Data block for global	Storage and scanning of 256
	binary values	binary values;
		especially for binary process
		inputs and outputs
GM	Data block for global	Storage and scanning of 256
	flags	internal binary statuses
GT	Data block for global	Storage and generation of times/
	times (timer)	timers for execution of time-
		dependent functions
FA	Data field block for	Storage of internal/external ana-
	analog values	log values with error 10-9;
		especially for internal results
FSA	Data field block for	Storage of internal/external ana-
	analog values	log values with error 10-4; espe-
		cially for internal results
FB	Data field block for	Storage of internal/external
	binary data	binary values; extension of GB/
		GM blocks

FC	Data field block for	Storage of characters (texts)
	characters

Blocks for signal exchange via CS 275

Type	Designation	Function
AKS	Analog coupling and	Transmission of up to 28 analog
	transmitter block	values and abbreviated time
		(minutes and seconds) from an
		AS 235 system to a max. of 6 or
		32 receivers (AKE blocks)

AKE	Analog coupling and	Reception of up to 28 analog val-
	receiver block	ues via the CS 275 from the data
		set of an MKS block of another
		bus participant
BKS	Binary coupling and	Transmission of up to 128 binary
	transmitter block	signals and abbreviated time
		from an AS 235 to a max. of 6 or
		32 receivers (BKE blocks)
BKE	Binary coupling and	Reception of up to 128 binary val-
	receiver block	ues via the CS 275 from the data
		set of a BKS block of another bus
		participant
ZKS	Character coupling	Transmission of up to four S16
	and transmitter block	strings from an AS 235 to up to 6
		or 32 receivers (ZKE blocks)
ZKE	Character coupling	Reception of up to four S16
	and receiver block	strings from another AS system
MKS	Alarm coupling and	Transition of 32 binary signals as
	transmitter block	alarms (with the time a signal
		changes from 0→1 or 1→0) to
		other bus participants
MKE	Alarm coupling and	Reception of 32 binary signals of
	receiver block	an MKS block and the time of
		transmission sent by another bus
		participant via the CS 275
SKS	Status coupling and	Transfer of status information to
	transmitter block	higher-level systems (operator
		system, computer)

PLPS	Reading and writing	Reading or writing of up to 20
	of parameters	parameters from a bus-coupled
		AS 235 system

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			System architecture
				Configuring
			Standard function blocks

Driver blocks for I/O modules
Type	Designation	Function		For modules with
				Order No.

AE	Analog input	Acquisition of an analog signal via an analog input module channel (0 to 20 mA,		6DS1 701-8AA, -8AB
		4 to 20 mA, 0 to ± 10 V; Pt 100 resistance thermometer, thermocouples) or an		6DS1 730-8AA
		analog input module of the SIMATIC S5 programmable controllers (instrument		6DS1 731-8AA/-8BA/
		range U)		-8EA/-8FA/-8RR +
		range U)		6DS1 703-8AB, -8RR
AR	Analog input allocation	Acquisition of 8 analog process variables, conversion into physical variables;		6DS1 703-8AB, -8RR
AR	Analog input allocation			6DS1 700-...
		storage in GA blocks or direct linking		6DS1 321-8AA 1)
AA	Analog output	Output of an analog signal via a channel of an analog output module or an ana-		6DS1 702-8AA, -8RR
		log output module of the SIMATIC S5 programmable controllers (instrument		6DS1 321-8AA 1)

range U)

BEI	Binary input	Acquisition of binary signals via a binary input module;
		storage of binary signals in GB block
BRA	Binary allocation	Acquisition of 8 binary signals via a binary input module;
		allocation of signals to specified linking addresses

6DS1 601-...

6DS1 602-...

6DS1 615-8AA

BAU	Binary output	Output of up to 32 binary signals to a binary output module	6DS1 603-...
	Binary output	Output of up to 32 binary signals to a binary output module	6DS1 603-...
			6DS1 604-8AA
			6DS1 605-8BA
RZ	Input block for two-channel	Acquisition of analog and binary signals from a channel of a two-channel con-	6DS1 402-...
	controller	troller module	6DS1 403-...
RZA	Output block for two-chan-	Transfer of the manipulated variable increment Y or setpoint increment W
	nel controller	from a closed-loop control block R or RN to a channel of a controller module
BU8	Binary transmitter monitor-	Acquisition and monitoring of 8 binary signals via a binary input module	6DS1 620-8AA
	ing block		6DS1 621-8AA
BU16	Binary transmitter monitor-	Acquisition and monitoring of 16 binary signals via a binary input module	6DS1 600-8AA
	ing block
ZE	Metered pulse input	Acquisition of a channel of a metered pulse input module	6DS1 607-8AB
DR	Input/output for speed con-	Acquisition of signals from the interface module, and transfer of signals to the	6DS1 303-8AA 2)
	trollers	interface module
E110	Binary input for SIMATIC	Reading in of 16 binary values from an interface module for input modules of	6DS1 310-8AA/8AB 1)
	S5 input modules	the SIMATIC S5-110 programmable controllers or for input modules of the	6DS1 321-8AA 1)
		SIMATIC S5 programmable controllers (instrument range U) or for standard	6DS1 600-8AA
		binary input modules	6DS1 601-8BA
			6DS1 602-8..
			6DS1 615-8AA
A110	Binary output for SIMATIC	Output of 16 binary values from an interface module for output modules of the	6DS1 310-8AA/8AB 1)
	S5 output modules	SIMATIC S5-110 programmable controllers or for output modules of the	6DS1 321-8AA 1)
		SIMATIC S5 programmable controllers (instrument range U) or for standard	6DS1 603-8..
		binary output modules	6DS1 604-8AA
			6DS1 605-8BA
S5KE	Coupling to S5	Acquisition of signals from the interface module via telegrams with point-to-	6DS1 333-8AB 1)
	- receive	point coupling
S5KS	Coupling to S5	Transfer of signals to the interface modules via telegrams with point-to-point	6DS1 333-8AB 1)
	- transmit	coupling
AEF	Analog input (field multi-	Driver for acquisition of analog signals via the field multiplexer analog input	6DS1 706-8AA
	plexer)	modules 2)	6DS1 710-8AA
AAF	Analog output (field multi-	Driver for acquisition of analog signals via the field multiplexer analog output	6DS1 711-8AA
	plexer)	modules 2)	6DS1 406-8AA/407-8AA
BEF	Binary input (field multi-	Driver for acquisition of binary signals via the binary signal input modules of the	6DS1 610-8AA
	plexer)	field multiplexer and for acquisition of fault signals from the binary I/O modules	6DS1 611-8AA
		of the field multiplexer 2)
BAF	Binary output (field multi-	Driver for output of binary signals via the binary signal output modules of the	6DS1 612-8AA
	plexer)	field multiplexer 2)
PRA	Testable relay module	Driver for output of 16 binary signals to a testable relay output module	6DS1 606-8BA
PBE	Testable binary input	Acquisition of binary signals via a testable binary input module, and transfer of	6DS1 618-8CA
		the binary signals to binary-value fields

1)Coupling module

2)No longer available

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System architecture

Configuring

Standard function blocks

Driver blocks for configurable TELEPERM ME I/O modules

Type	Designation	Function	For modules with
			Order No.
MSB	Motor/valve and actuator	Acquisition and transfer of binary signals to the binary generation module	6DS1 717-8AA/-8RR
	control		+ 6DS1 719-8AA/-8RR
TVB	Preselection and subloop	Acquisition and transfer of binary signals to the binary calculation module for	6DS1 717-8AA/-8RR
	control	operation and monitoring of a preselection or subloop control
BRBK	Organization and binary	Acquisition of binary signals from the flag area of the binary calculation module,	6DS1 717-8AA/-8RR
	input/output block	coordination together with ABR, MSB or TVB
ABR	Analog input and output	Acquisition and transfer of analog signals to the analog extension module via	6DS1 717-8AA/-8RR
		the binary calculation module	+ 6DS1 720-8AA
REN	Analog/binary inputs and	Acquisition and transfer of analog and binary signals of the analog calculation	6DS1 715-8BB
	output	module
RSK	Closed-loop control mod-	Acquisition of signals from single-channel and two-channel configurable	6DS1 408-8BB
RSKB	ule driver	closed-loop control modules	6DS1 410-8BB
RSKB	Operation block for RSK	For operation and monitoring of configurable closed-loop control modules,	6DS1 411-8AA/-8RR
			6DS1 411-8AA/-8RR
			6DS1 412-8AA/-8RR
	block	together with RSK block

Driver blocks for I/O modules with standardized display

Type	Designation	Function	For modules with
			Order No.
RE	Closed-loop controller,	Acquisition of signals from single-channel closed-loop control modules;	6DS1 400-8BA
	single-channel	transfer of commands and standardized increments to the closed-loop control	(S controller)
RK		modules	6DS1 401-8BA
RK		As RE, with additional functions	(K controller)
		As RE, with additional functions
EM	Individual control drive,	Acquisition of signals from individual control drive modules and application of	6DS1 500-8BA
	motor	signals to the binary outputs, e.g. for a subgroup control; transfer of commands	6DS1 502-8BA
		to the individual control drive modules
EU		As EM, with additional functions
EV	Individual control drive,	As EM, for the corresponding modules	6DS1 501-8BA/-8BB
EK	valve	As EV, with additional functions	6DS1 503-8BA
EK		As EV, with additional functions
DZ	Proportioning counter	Acquisition of signals from proportioning counter modules (2/4 channels);	6DS1 613-8BB
		connection of these signals to the block outputs;
		transfer of commands and standardized analog values
EG	Individual control drives	Acquisition of signals from modules;	6DS1 504-8AA
	(4 to 8 channels)	connection of these signals to the binary outputs;	6DS1 505-8AA
		transfer of commands
FM	Field multiplexer	Acquisition of signals from a channel of the interface module for FM 100 field	6DS1 304-8AA
		multiplexer 1); transfer of signals to the module	6DS1 304-8BB

1) No longer available

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System architecture

Configuring

						Standard function blocks

Output blocks for printer and process monitor			Test blocks
Type	Designation	Function		Type	Designation	Function

GP	Group display
MEL	Alarm output
BILD
BILD	Display output
+LAYO
PROT	Log output
+LAYO
PKF	Process coupling/
	alarm sequence dis-
	play

Design of display hierarchy:	TANZ	Test display	Monitoring of binary and analog
area display and group display			variables;
Output of planned plain text			selective access to variables
Output of planned plain text			possible (max. 16 analog and 16
alarms with time (resolution 1 s);			possible (max. 16 analog and 16
alarms with time (resolution 1 s);			binary within a standard display)
also standard blocks, such as M,			binary within a standard display)
also standard blocks, such as M,	TUEB
generate alarms	TUEB	Test monitoring	For sequence monitoring of TML
Output of plant-specific displays			programs for:
Output of plant-specific displays			• Cyclic sequence monitoring
			• Cyclic sequence monitoring
Output of plant-specific logs on			• Non-recurring monitoring of a
Output of plant-specific logs on			program run
printers			program run
printers			(up to 248 TML programs can be
Output of PKM alarms			(up to 248 TML programs can be
Output of PKM alarms			monitored)
			monitored)
	SYST.	Test and mainte-	Menu-controlled calling of main-
	WART	nance	tenance programs:

Organization blocks

Type	Designation	Function
XB	Processing, cyclic	To inhibit/release a group of func-
		tion blocks and to release each
		n-th cycle
XA	Processing, acyclic	To inhibit/non-recurring release a
		sequence of function blocks.
		When installed in the alarm level
		(ZYK 1) as an ALARM block:
		1 x execution of subsequent
		block sequence
XZ
XZ	Time start	For time-dependent switching-
FUTA		on/off of XB blocks
		on/off of XB blocks
	Function keys	For switching-on/off of XA/XB
		blocks by operator input
RNAM
RNAM	Rename	Modification of type name or
		block name
APRO+	TML connection	To insert a user-specific TML pro-
PROB	(of PROBLEM	gram into the execution list
	blocks)

•XB switchover

•CS 275 coupling status

•Activate error messages

•TML

•Reloading and selective archiving

•System settings

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System architecture

	2/2	Performance characteristics
	2/4	Redundancy with AS 235 H
Configuring
	2/5	Standard function blocks
	2/10	User function blocks

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2/1

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System architecture

Performance characteristics

The systems can either be used on their own with local operation and monitoring, or coupled in system networks with central operation and monitoring.

System configuration

The automation systems consist of:

•A basic unit (AS 235, AS 235 H) or a basic system (AS 235 K)

•ES 100 K extension systems (wall housing) or extension units (for fitting in cabinets) as extension for configuring with input/ output modules.

Standard input/output devices enable local communication with the automation system during the configuring and commissioning phases as well as during later operation. The following can be connected:

•54-cm (21-inch) process monitors

•Process operation keyboard and configuring keyboard, max. 2 of each for 2 independent operating consoles

•Max. 4 logging printers

•1 mini floppy disk unit for booting the system memory and for loading/saving the user memory.

Basic system/basic unit

The basic unit (AS 235, AS 235 H) or the basic system (AS 235 K) mainly contains

• the power supply modules,

I/O modules

There are the following groups of I/O modules:

•Signal modules

•Function modules

•Calculation modules

•Coupling modules.

Signal modules are required for input and output of the process signals, usually without further processing (exception: adaptation of characteristic with temperature measurements).

The calculation modules enable the configuring of individual user functions.

Memory, configuring

The memory with battery backup of the automation systems is divided into:

•a system memory and

•a user memory.

•the central processor module,

•a memory module with user memory with 4,000 Kbyte capacity and battery backup and

•the interface modules for the input and output devices and the CS 275 bus system,

each of which is redundant in the AS 235 H system.

The basic unit of the AS 235 and the basic system of the

AS 235 K each has 6 slots for I/O modules. No I/O modules can be plugged into the basic unit of the AS 235 H systems.

The following can be fitted into the systems as standard:

• AS 235	Max. 90	I/O modules
	(basic unit + 6 extension units)
• AS 235	H Max. 91	I/O modules
	(7 extension units)
• AS 235	K Max. 108 I/O modules

(basic system + eight ES 100 K extension systems)

The number of usable I/O slots with the AS 235 and AS 235 H can be increased by additional use of ES 100 K extension systems:

•AS 235 Max. 114 I/O modules

•AS 235 H Max. 103 I/O modules

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System architecture

STEP M

In addition to the function blocks for binary processing, the AS 235/235 H/235 K systems can use the STEP M control lan-

guage, without leaving the block configuration, in order to formulate extensive and complex open-loop control tasks.

TML language

Operation and monitoring

Scope of performance

•30 to 80 control loops

•50 to 120 additional analog-value monitoring functions

•5 to 15 sequential controls

•100 to 250 logic controls

•Any number of flow charts (up to 8 colors) and individually designed logs.

Performance characteristics

Summary of system properties

•Automation system for autonomous operation with local communication or for network operation with central communication

•Fitted in wall housing or cabinet

•Configurable within wide limits

(up to 114 I/O modules depending on system)

•User memory up to 4,000 Kbytes on one module

•32-bit processing of analog values

•Optimized data transfer rate resulting from separate processing of analog and binary values

•Central unit redundant as option with synchronous processing of clocks (AS 235 H)

•Operation without fans possible

•Complete range of standard function blocks

•User function blocks with convenient TML programming language, also STEP M programming language for open-loop control tasks

•Configuring/programming either online without programmer (using lists) or with PC (using graphics)

•Local or central configuring (via bus)

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System architecture

Redundancy with AS 235 H

CS 275

plant bus

Central

Synchronization

Central

processing

unit I

unit II

Comparison,

cross-coupling

Redundant I/O bus

Comparison,

switchover

I/O bus

I/O

modules

Process level

Redundant path

Fig. 2/1 1-out-of-2 redundancy structure with AS 235 H

Redundancy with the AS 235 H automation system

According to VDI/VDE 3542 the following applies:

The fully-synchronous mode of operation of the two partial

When connected to the CS 275 bus system, the redundant AS 235 H system responds like a single participant.

Important note:

AS 235 / AS 235 K systems which make a dangerous operating state impossible should faults occur in the automation system.

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System architecture

Configuring

Standard function blocks

Blocks for binary processing

The configuration of the automation structure is usually generated graphically using the PROGRAF AS+ configuring tool (see also page 2/9).

The following tables list the standard function blocks divided according to their areas of application.

Blocks for analog and digital processing

Type	Designation	Function
SUM	Adder	Y = X1 + X2 - X3 - X4
MUL	Multiplier	Y = X1 · X2
DIV	Divider	Y = X1/X2

RAD	Square-root extractor	Y =	X or Y = K X
LN	Logarithm extractor	Y = KF · Ioge \| X \|
EXP	Exponential value	Y = ex
ABS	Absolute value	X = \| X \|

INT	Integrator	Y = K · X dt, K = 1/T
DIF	Differentiator	Y(s)/X(s) = (T·s)/(1 + (T·s/v))
PT
PT	Delay	Y(s)/X(s) = 1/(1 + T·s)
TOZ	Dead time	Y(s)/X(s) = e-s·T
MIN	Minimum-value	Y = minimum of X1, X2, X3
	selector
MAX	Maximum-value	Y = maximum of X1, X2, X3
	selector
TOB	Dead band	Y = X-TOBU for X < TOBU
		0	for TOBU ≤X ≤TOBO
		X-TOBO for X > TOBO
PLG	Function generator	Linear interpolation between 6
		pairs of turning points
GW	Limit monitor	Limit check between two switch-
		ing points
ASL	Analog-value switch	Y = X1 for S = “0”
		Y = X2 for S = “1”
SPEI	Analog-value mem-	Storage of up to 256 analog val-
	ory	ues

Type	Designation	Function
VU	AND	A = E1 E2 E3
VO	OR	A = E1 E2 E3
VN	Negation	A =
			E
VM	Flag	Flag of binary input signals (flip-
		flop)
VZ	Time delay	Switch-on and switch-off delays
VS + STEP	STEP M block	Freely programmable in STEP M
MPX	Multiplexer	To supply the STEP commands in
		the following VS/KS block
BW	Binary selection	Selection of status combination
		from up to 3 binary signals
INKU	Incremental con-	Converts analog value into an
	verter	open or close pulse
BCE	BCD input	Conversion of a BCD signal into
		an analog value
BCA	BCD output	Conversion of an analog value
		into a BCD signal
KA	Sequence start	Marks the start of an ON/OFF
		branch of a subgroup control
KAK		As KA, but with additional func-
		tions

KB	Sequence	Conditions of a control step, for
		power plants
KBK		As KB, but with additional func-
		tions
KS	Sequence step	As KB, for process plants
KV
	Sequence branch	Branch of a sequence into a max-
		imum of 6 branches, with process
		plants
KE	Sequence end	Last block in a sequence
KEK		As KE, but with additional func-
		tions
HA	Auxiliary oil auto-	Controls electric auxiliary oil
	matic unit	pumps for oil supply to generator
		sets
HUP	Horn block	Triggers signalling equipment
		(optical and audible)
EAR	Individual analog-	Allocates analog values from out-
	value allocation	puts in GA blocks
EBR	Single-bit allocation	Links individual binary outputs to
		GB/GM data blocks
UBR	Universal binary	Links 16 binary outputs to GB/
	location	GM data blocks

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System architecture

Configuring

Standard function blocks

Blocks for processing with standardized operation and monitoring

Type

Designation

Function

RClosed-loop controlPID control, e.g. for disturbance

	ler	variable feedforward, tracking of
		setpoint and manipulated vari-
		able, limit formation
RN		As R,
		with additional functions

M	Measured-value	Monitors a measured value for 3
	monitoring	pairs of limits
		Extension of a closed-loop con-
		trol block for limit monitoring
		Limitation of measured value at
		the error limits
V	Ratio	Generation of a ratio, e.g. with a
		ratio control
		Proportional adjuster, e.g. with
		synchronization control or to influ-
		ence the command variable in a
		cascade
B
B	Operation block	Display of analog values (internal
		result of calculations, ...)
		Access to analog and binary val-
		ues (input of constants, ...)
S	Control unit	Operation and monitoring of a
		sequence in process plants
G	Subgroup control	Operation and monitoring of
		sequences in power plants
GK	Group control	As G,
GK		with additional functions
A	Output for binary	Display of and access to a binary
	data	value
F	Window block	Display of 5 measured values;
		each of the 5 values is monitored
		for a pair of limits
FN	Window block	Display and limit monitoring of 5
		measured values;
		input of 5 pairs of limits each with
		hysteresis as well as 5 ranges for
		the measured value display
T	Trend 1)	Display of the trend of 2 mea-
		sured values as a bargraph; time
		base between 1.625 s and 36 h
SR	Recorder 1)	Summary of up to 4 series of
		measurements, displayed on
		screen as dashed-line curves;
		4 pairs of limits for monitoring the
		measured values
C	Selector	To switch over binary signals,
		e.g. manual/automatic mode
PKM	Alarm acquisition	Acquires planned alarms from
		binary input module/GB block
PKF	Alarm sequence dis-	Output of PKM alarms; new
	play 1)	alarms of PKM blocks, display of
		alarm history

1) Displays in PROGRAF AS+

Data blocks

Type	Designation	Function
GA	Data block for global	Storage of 256 analog values
	analog values	with error 10-9;
		storage of process image, histor-
		ical values etc.
GB	Data block for global	Storage and scanning of 256
	binary values	binary values;
		especially for binary process
		inputs and outputs
GM	Data block for global	Storage and scanning of 256
	flags	internal binary statuses
GT	Data block for global	Storage and generation of times/
	times (timer)	timers for execution of time-
		dependent functions
FA	Data field block for	Storage of internal/external ana-
	analog values	log values with error 10-9;
		especially for internal results
FSA	Data field block for	Storage of internal/external ana-
	analog values	log values with error 10-4; espe-
		cially for internal results
FB	Data field block for	Storage of internal/external
	binary data	binary values; extension of GB/
		GM blocks

FC	Data field block for	Storage of characters (texts)
	characters

Blocks for signal exchange via CS 275

Type	Designation	Function
AKS	Analog coupling and	Transmission of up to 28 analog
	transmitter block	values and abbreviated time
		(minutes and seconds) from an
		AS 235 system to a max. of 6 or
		32 receivers (AKE blocks)

AKE	Analog coupling and	Reception of up to 28 analog val-
	receiver block	ues via the CS 275 from the data
		set of an MKS block of another
		bus participant
BKS	Binary coupling and	Transmission of up to 128 binary
	transmitter block	signals and abbreviated time
		from an AS 235 to a max. of 6 or
		32 receivers (BKE blocks)
BKE	Binary coupling and	Reception of up to 128 binary val-
	receiver block	ues via the CS 275 from the data
		set of a BKS block of another bus
		participant
ZKS	Character coupling	Transmission of up to four S16
	and transmitter block	strings from an AS 235 to up to 6
		or 32 receivers (ZKE blocks)
ZKE	Character coupling	Reception of up to four S16
	and receiver block	strings from another AS system
MKS	Alarm coupling and	Transition of 32 binary signals as
	transmitter block	alarms (with the time a signal
		changes from 0→1 or 1→0) to
		other bus participants
MKE	Alarm coupling and	Reception of 32 binary signals of
	receiver block	an MKS block and the time of
		transmission sent by another bus
		participant via the CS 275
SKS	Status coupling and	Transfer of status information to
	transmitter block	higher-level systems (operator
		system, computer)

PLPS	Reading and writing	Reading or writing of up to 20
	of parameters	parameters from a bus-coupled
		AS 235 system

2/6	Siemens PLT 111 · 1999

This catalog is out of date, see note on page 1

			System architecture
				Configuring
			Standard function blocks

Driver blocks for I/O modules
Type	Designation	Function		For modules with
				Order No.

AE	Analog input	Acquisition of an analog signal via an analog input module channel (0 to 20 mA,		6DS1 701-8AA, -8AB
		4 to 20 mA, 0 to ± 10 V; Pt 100 resistance thermometer, thermocouples) or an		6DS1 730-8AA
		analog input module of the SIMATIC S5 programmable controllers (instrument		6DS1 731-8AA/-8BA/
		range U)		-8EA/-8FA/-8RR +
		range U)		6DS1 703-8AB, -8RR
AR	Analog input allocation	Acquisition of 8 analog process variables, conversion into physical variables;		6DS1 703-8AB, -8RR
AR	Analog input allocation			6DS1 700-...
		storage in GA blocks or direct linking		6DS1 321-8AA 1)
AA	Analog output	Output of an analog signal via a channel of an analog output module or an ana-		6DS1 702-8AA, -8RR
		log output module of the SIMATIC S5 programmable controllers (instrument		6DS1 321-8AA 1)

range U)

BEI	Binary input	Acquisition of binary signals via a binary input module;
		storage of binary signals in GB block
BRA	Binary allocation	Acquisition of 8 binary signals via a binary input module;
		allocation of signals to specified linking addresses

6DS1 601-...

6DS1 602-...

6DS1 615-8AA

BAU	Binary output	Output of up to 32 binary signals to a binary output module	6DS1 603-...
	Binary output	Output of up to 32 binary signals to a binary output module	6DS1 603-...
			6DS1 604-8AA
			6DS1 605-8BA
RZ	Input block for two-channel	Acquisition of analog and binary signals from a channel of a two-channel con-	6DS1 402-...
	controller	troller module	6DS1 403-...
RZA	Output block for two-chan-	Transfer of the manipulated variable increment Y or setpoint increment W
	nel controller	from a closed-loop control block R or RN to a channel of a controller module
BU8	Binary transmitter monitor-	Acquisition and monitoring of 8 binary signals via a binary input module	6DS1 620-8AA
	ing block		6DS1 621-8AA
BU16	Binary transmitter monitor-	Acquisition and monitoring of 16 binary signals via a binary input module	6DS1 600-8AA
	ing block
ZE	Metered pulse input	Acquisition of a channel of a metered pulse input module	6DS1 607-8AB
DR	Input/output for speed con-	Acquisition of signals from the interface module, and transfer of signals to the	6DS1 303-8AA 2)
	trollers	interface module
E110	Binary input for SIMATIC	Reading in of 16 binary values from an interface module for input modules of	6DS1 310-8AA/8AB 1)
	S5 input modules	the SIMATIC S5-110 programmable controllers or for input modules of the	6DS1 321-8AA 1)
		SIMATIC S5 programmable controllers (instrument range U) or for standard	6DS1 600-8AA
		binary input modules	6DS1 601-8BA
			6DS1 602-8..
			6DS1 615-8AA
A110	Binary output for SIMATIC	Output of 16 binary values from an interface module for output modules of the	6DS1 310-8AA/8AB 1)
	S5 output modules	SIMATIC S5-110 programmable controllers or for output modules of the	6DS1 321-8AA 1)
		SIMATIC S5 programmable controllers (instrument range U) or for standard	6DS1 603-8..
		binary output modules	6DS1 604-8AA
			6DS1 605-8BA
S5KE	Coupling to S5	Acquisition of signals from the interface module via telegrams with point-to-	6DS1 333-8AB 1)
	- receive	point coupling
S5KS	Coupling to S5	Transfer of signals to the interface modules via telegrams with point-to-point	6DS1 333-8AB 1)
	- transmit	coupling
AEF	Analog input (field multi-	Driver for acquisition of analog signals via the field multiplexer analog input	6DS1 706-8AA
	plexer)	modules 2)	6DS1 710-8AA
AAF	Analog output (field multi-	Driver for acquisition of analog signals via the field multiplexer analog output	6DS1 711-8AA
	plexer)	modules 2)	6DS1 406-8AA/407-8AA
BEF	Binary input (field multi-	Driver for acquisition of binary signals via the binary signal input modules of the	6DS1 610-8AA
	plexer)	field multiplexer and for acquisition of fault signals from the binary I/O modules	6DS1 611-8AA
		of the field multiplexer 2)
BAF	Binary output (field multi-	Driver for output of binary signals via the binary signal output modules of the	6DS1 612-8AA
	plexer)	field multiplexer 2)
PRA	Testable relay module	Driver for output of 16 binary signals to a testable relay output module	6DS1 606-8BA
PBE	Testable binary input	Acquisition of binary signals via a testable binary input module, and transfer of	6DS1 618-8CA
		the binary signals to binary-value fields

1)Coupling module

2)No longer available

Siemens PLT 111 · 1999

2/7

This catalog is out of date, see note on page 1

System architecture

Configuring

Standard function blocks

Driver blocks for configurable TELEPERM ME I/O modules

Type	Designation	Function	For modules with
			Order No.
MSB	Motor/valve and actuator	Acquisition and transfer of binary signals to the binary generation module	6DS1 717-8AA/-8RR
	control		+ 6DS1 719-8AA/-8RR
TVB	Preselection and subloop	Acquisition and transfer of binary signals to the binary calculation module for	6DS1 717-8AA/-8RR
	control	operation and monitoring of a preselection or subloop control
BRBK	Organization and binary	Acquisition of binary signals from the flag area of the binary calculation module,	6DS1 717-8AA/-8RR
	input/output block	coordination together with ABR, MSB or TVB
ABR	Analog input and output	Acquisition and transfer of analog signals to the analog extension module via	6DS1 717-8AA/-8RR
		the binary calculation module	+ 6DS1 720-8AA
REN	Analog/binary inputs and	Acquisition and transfer of analog and binary signals of the analog calculation	6DS1 715-8BB
	output	module
RSK	Closed-loop control mod-	Acquisition of signals from single-channel and two-channel configurable	6DS1 408-8BB
RSKB	ule driver	closed-loop control modules	6DS1 410-8BB
RSKB	Operation block for RSK	For operation and monitoring of configurable closed-loop control modules,	6DS1 411-8AA/-8RR
			6DS1 411-8AA/-8RR
			6DS1 412-8AA/-8RR
	block	together with RSK block

Driver blocks for I/O modules with standardized display

Type	Designation	Function	For modules with
			Order No.
RE	Closed-loop controller,	Acquisition of signals from single-channel closed-loop control modules;	6DS1 400-8BA
	single-channel	transfer of commands and standardized increments to the closed-loop control	(S controller)
RK		modules	6DS1 401-8BA
RK		As RE, with additional functions	(K controller)
		As RE, with additional functions
EM	Individual control drive,	Acquisition of signals from individual control drive modules and application of	6DS1 500-8BA
	motor	signals to the binary outputs, e.g. for a subgroup control; transfer of commands	6DS1 502-8BA
		to the individual control drive modules
EU		As EM, with additional functions
EV	Individual control drive,	As EM, for the corresponding modules	6DS1 501-8BA/-8BB
EK	valve	As EV, with additional functions	6DS1 503-8BA
EK		As EV, with additional functions
DZ	Proportioning counter	Acquisition of signals from proportioning counter modules (2/4 channels);	6DS1 613-8BB
		connection of these signals to the block outputs;
		transfer of commands and standardized analog values
EG	Individual control drives	Acquisition of signals from modules;	6DS1 504-8AA
	(4 to 8 channels)	connection of these signals to the binary outputs;	6DS1 505-8AA
		transfer of commands
FM	Field multiplexer	Acquisition of signals from a channel of the interface module for FM 100 field	6DS1 304-8AA
		multiplexer 1); transfer of signals to the module	6DS1 304-8BB

1) No longer available

2/8	Siemens PLT 111 · 1999

This catalog is out of date, see note on page 1

System architecture

Configuring

						Standard function blocks

Output blocks for printer and process monitor			Test blocks
Type	Designation	Function		Type	Designation	Function

GP	Group display
MEL	Alarm output
BILD
BILD	Display output
+LAYO
PROT	Log output
+LAYO
PKF	Process coupling/
	alarm sequence dis-
	play

Design of display hierarchy:	TANZ	Test display	Monitoring of binary and analog
area display and group display			variables;
Output of planned plain text			selective access to variables
Output of planned plain text			possible (max. 16 analog and 16
alarms with time (resolution 1 s);			possible (max. 16 analog and 16
alarms with time (resolution 1 s);			binary within a standard display)
also standard blocks, such as M,			binary within a standard display)
also standard blocks, such as M,	TUEB
generate alarms	TUEB	Test monitoring	For sequence monitoring of TML
Output of plant-specific displays			programs for:
Output of plant-specific displays			• Cyclic sequence monitoring
			• Cyclic sequence monitoring
Output of plant-specific logs on			• Non-recurring monitoring of a
Output of plant-specific logs on			program run
printers			program run
printers			(up to 248 TML programs can be
Output of PKM alarms			(up to 248 TML programs can be
Output of PKM alarms			monitored)
			monitored)
	SYST.	Test and mainte-	Menu-controlled calling of main-
	WART	nance	tenance programs:

Organization blocks

Type	Designation	Function
XB	Processing, cyclic	To inhibit/release a group of func-
		tion blocks and to release each
		n-th cycle
XA	Processing, acyclic	To inhibit/non-recurring release a
		sequence of function blocks.
		When installed in the alarm level
		(ZYK 1) as an ALARM block:
		1 x execution of subsequent
		block sequence
XZ
XZ	Time start	For time-dependent switching-
FUTA		on/off of XB blocks
		on/off of XB blocks
	Function keys	For switching-on/off of XA/XB
		blocks by operator input
RNAM
RNAM	Rename	Modification of type name or
		block name
APRO+	TML connection	To insert a user-specific TML pro-
PROB	(of PROBLEM	gram into the execution list
	blocks)

•XB switchover

•CS 275 coupling status

•Activate error messages

•TML

•Reloading and selective archiving

•System settings

Siemens PLT 111 · 1999

2/9

Siemens AS 235, AS 235 H, AS 235 K User Manual

This catalog is out of date, see note on page 1

Automation systems

	3/2	General
AS 235
	3/3	Basic cabinet
	3/6	Ordering data for basic cabinet
	3/7	Options for basic cabinet
	3/8	Extension cabinet
	3/8	Ordering data for extension cabinet
	3/8	Options for extension cabinet
AS 235 H
	3/9	Basic cabinet
	3/14	Ordering data for basic cabinet
	3/15	Options for basic cabinet
	3/16	Extension cabinet
	3/17	Ordering data for extension cabinet
	3/17	Options for extension cabinet
AS 235 K
	3/18	Basic system
	3/20	Ordering data for AS 235 K
	3/20	Options for AS 235 K
ES 100 K
	3/21	ES 100 K extension system
	3/22	Ordering data for ES 100 K
	3/22	Options for ES 100 K
Standard cabinets
	3/23	Standard cabinets and accessories
	3/23	Ordering data for system cabinet
		accessories
	3/25	Permissible thermal loading
	3/26	Standard cabinets IP 20
		without heat exchanger
	3/27	Standard cabinets IP 54
		with heat exchanger
Process connection
systems
	3/28	Process connection systems
Connection diagrams
	3/29	Standard I/O devices to
		AS 235 / AS 235 K
	3/30	Connection of personal computer
	3/31	Connection of process monitors and
		parallel monitors
	3/32	Standard I/O devices to AS 235 H
	3/34	Summary of connecting cables

Siemens PLT 111 · 1999

3/1

This catalog is out of date, see note on page 1

Automation systems

General

AS 235 K	ES 100 K	ES 100 K
			EE4
			GE
			AS 235
			EE5
	ES 100 K	Further	EE1
		ES 100 K systems,	EE1
		ES 100 K systems,
		max. 4	EE6
			EE6
			EE2
			EE3
		ES 100 K

a Distributed configuration:	b	Central configuration: AS 235 automation system with



		basic and extension cabinets, max 6 extension units

AS 235 K automation system,
AS 235 K automation system,
can be extended by up to eight	EE	Extension unit
ES 100 K extension systems	GE	Basic unit
ES 100 K extension systems	GE	Basic unit

Fig. 3/1 Distributed and central configuration of AS 235 automation systems

General

The AS 235 automation system is available in three different versions:

•AS 235 cabinet version,

•AS 235 H high-availability cabinet version and

•AS 235 K compact version.

The I/O modules in the AS 235 and AS 235 H automation systems are in 6-U high subracks of the ES 902 packaging system, the extension units, which are only suitable for cabinet installation. A further 6 slots for I/O modules are available in the AS 235 basic unit.

The extension units are first installed in the basic cabinet of the AS 235/AS 235 H systems according to the numbers required for the respective automation task. If the basic cabinet is full, the remaining extension units are accommodated in the extension cabinet.

An AS 235 system can be fitted in this manner with up to 90 I/O modules, an AS 235 H system with up to 91 I/O modules. The number of available I/O slots can be increased to max. 114 (AS 235) or max. 103 (AS 235 H) by using additional ES 100 K extension systems.

In contrast to the AS 235 K automation system, the AS 235 and AS 235 H systems installed in cabinets are primarily designed for central configurations (Fig. 3/1b).

The main selection criterion for the AS 235 H system is its high availability.

The AS 235 K compact version is the smallest operable AS 235 automation system. It is fitted in a 15-U 1) high subrack of the ES 902 packaging system (DIN 41494) which in turn is installed in a sheet-steel housing with degree of protection IP 21. The housing is designed for wall mounting.

The basic system of the AS 235 K has 6 slots for I/O modules. Up to 8 independent ES 100 K extension systems can be connected, thus increasing the total number of I/O modules to 108.

The ES 100 K extension systems can be installed up to 500 m away from the AS 235 K automation system.

For these reasons, the AS 235 K system is primarily suitable for distributed configurations (Fig. 3/1a) in small and medium-size plants or as a stand-alone system.

1) 1 U corresponds to 44.5 mm.

3/2	Siemens PLT 111 · 1999

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AS 235 automation system

The AS 235 automation system is the cabinet version of the range. It can be ordered in the form of two ordering units: basic cabinet and extension cabinet:

The basic cabinet is the main component of the AS 235 automation system. It contains all components required for the AS 235 system to function. It can therefore also be used on its own, i.e. without an extension cabinet.

The extension cabinet increases the number of slots for I/O modules. It can only be operated in conjunction with the basic cabinet with up to 3 extension units. When using an extension cabinet it is possible to increase the number of slots for I/O modules in the basic cabinet (48) up to a maximum of 90.

Basic cabinet

The basic cabinet consists of the following main components:

Basic unit

The basic unit of the AS 235 automation system consists of:

• Subrack
– For wire-wrap system	6DS9 026-8AB
– For Maxi-Termi-Point system	6DS9 026-8AA
• Power supply subrack with
– Slots for power supply and
logic modules and
– 6 slots for I/O modules
• Power supply module
– DC 24 V / DC 24 V	C79451-A3260-A25
– DC 24 V / DC 5 V	C79451-Z1359-U9
• Alarm logic module	6DS1 901-8BA
• Central processing unit with
– Central processor module	6DS1 140-8AA
– EDC memory module 4000 Kbyte	6DS1 844-8FA
– Backup battery for memory module	W79084-U1001-B2
– AS 235 system software, version G	6DS5 323-8AG
– Interface module for I/O bus 1	6DS1 312-8BB
• Interface module for mini floppy disk unit	6DS1 326-8BB
• Interface module for operation channel 1	6DS1 330-8CA
• Bus terminator module	C79458-L445-B20
• Cable duct, 2 U high	6DS9 906-8AB
• Cover with wiring duct	6DS9 927-8AA
• Cable set for power supply and alarms	6DS9 908-8CA

Automation systems

AS 235

Basic cabinet

Communication

via CS 275 plant bus

GE		M
SV	SV	M
		L

6 I/O	ZE
modules

I/O bus
EE
14 I/O	MO
modules	(max. 6)

DR	Printer
DR	Printer	PBT, ST
EE	Extension unit
GE	Basic unit
ML	Alarm logic module
MO	Monitor
PBT	Process operation keyboard DR
ST	Configuring keyboard
SV	Power supply module
UI	Bus converter
ZE	Central unit

Fig. 3/2 AS 235 automation system, system configuration

The alarm logic modules monitor the voltages L+, PM (DC 24 V each) and +5 V as well as the I & C signals for overtemperature, door contacts, fan contacts and spare contacts, and trigger the current lamps.

The central processor is especially tailored to the processing of closed-loop and open-loop control tasks and to the TML programming language. It divides the RAM and differentiates access operations to

The subrack for the basic unit of the AS 235 system corresponds to the ES 902 system and is 10 U high. It is the supporting system for the other components of the basic unit, the interface modules for the local bus, and the I/O modules. The process signal lines for the 6 I/O modules are connected to the rear, the plug connectors are equipped with wire-wrap or Multi-Termi-Point connections.

If the process signal cables leading to I/O slot 6 are to the connected in the cabinets also using the Maxi-Termi-Point system, conversion is necessary using SAE cabinet connection elements. These must be ordered separately.

The power supply module C79451-A3260-A25 is used to supply the basic unit with DC 24 V. The DC 24 V supply voltage is filtered and additionally fused on this module. Two process operation keyboards and a mini floppy disk unit can be powered with DC 24 V via 3 sockets on the front of the module.

The basic unit is equipped with 1 or 2 alarm logic modules depending on the configuration of the automation system. The alarm logic module ML1 is assigned to the basic cabinet. The alarm logic module ML2 is only required if the AS 235 system consists of a basic cabinet and an extension cabinet and has a basic unit with wire-wrap pins. In the case of the basic unit with Maxi-Termi-Point system, the tasks of the alarm logic module ML2 are handled by the interface module for I/O bus 2.

•the 1-Mbyte system RAM with battery backup for all fixed system data and programs,

•the 4000-Kbyte RAM with battery backup for all user programs and data and for variable system data, and

•the transfer memories of the interface modules for I/O bus, operation channel, mini floppy disk unit and local bus.

The memory module with Error Detection and Correction EDC can correct a 1-bit error when reading, and eliminate it in the memory cell together with the system software.

The interface module for I/O bus establishes the connection between the 8-bit central unit bus and the I/O bus. One or two of these modules can be plugged into the basic unit of the AS 235 system:

•The interface module for I/O bus 1 (A) supplies the I/O modules plugged into slots 1 to 5 of the basic unit and the 3 extension units of the basic cabinet. It is always required, and belongs to the standard delivery of the basic unit.

•The interface module for I/O bus 2 (B) must the ordered as an option. It connects slot 6 for I/O modules in the basic unit and the 3 extension units of the extension cabinet to the central processing unit via I/O bus 2 (B). It is therefore only required if slot 6 in the basic unit is to be used, or if an extension cabinet is used in addition to the basic cabinet.

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