This catalog is out of date, see note on page 1

System architecture

Configuring

Standard function blocks

Blocks for processing with

￿

 

 

 

standardized operation and monitoring

 

Type

Designation

Function

 

R

Closed-loop control-

PID 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

 

 

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,

 

 

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/

￿FA

times (timer)

timers for execution of time-

 

dependent functions

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

￿BKE

transmitter block

signals and abbreviated time

 

from an AS 235 to a max. of 6 or

 

32 receivers (BKE blocks)

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 01 or 10) 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

Page 12
Image 12
Siemens AS 235 appendix Data blocks, Blocks for signal exchange via CS