Siemens PGC 302 Edition II - Connection of External Status Signals and Digital Inputs

Digital
input
Use
+ 24 V means
Terminal on
terminal board
1
2
3
4
5
6
7
8
Peripheral boards faulty
Housing purging o.k.
Housing temperature o.k.
Gas supply o.k.
External unit A not ready
External unit B not ready
Reserved
Reserved
57
58
59
60
61
62
63
64
Ground 1 to 8 65
9
10
11
12
13
14
15
16
Not used
Not used
Not used
Not used
Not used
Not used
Not used
Not used
66
67
68
69
70
71
72
73
Ground 9 to 16 74
Connection
of status messages to control room
Several status messages of the chromatograph are con-
nected as digital signals to the terminal board. More
details can be found in the register External wiring di-
agrams.
Analyzer failure
The signal Analyzer failure of the chromatograph is
connected to the terminal board as digital output 1.
24 V signal at terminal 30, ground e.g. at terminal 38.
In addition there is a relay contact connected to the
terminals 8 and 9. Contact opened means: Analyzer
failure.
Maintenance request
The second digital output has the meaning Maintenance
request. You can connect this signal to a lamp or horn in
the control room (see Operation using keyboard and
screen: Status). 24 V signal at terminal 31, ground e.g.
at terminal 38.
Purging pressure, zone 2
An excess pressure switch is fitted in chromatographs
for zone 2. It is closed if the purging pressure is o.k. It
is possible to monitor the purging pressure, e.g. from
the control unit, if 24 V are routed to digital output 2
via this switch.
Connection of external
status signals and digital inputs
The chromatograph monitors the following status sig-
nals:
Carrier gas pressure or supply gases
Start delay by external device A
Start delay by external device B
Further monitoring functions can be carried out using
BASIC
programs.
The status signals must be present as floating contacts.
They are wired directly to the terminal board.
16 digital inputs are present on the terminal board. The
first 8 are for internal purposes. This is shown in the
following table.
SIMATIC
- modules are required for further digital in-
puts. To connect these modules, refer in this register to
SIMATIC
modules: Digital inputs or in the register Ex-
ternal wiring diagrams.
Overpressure
switch
4
5
+24 V
GND
DI 9
66
74
GND
Connection of digital inputs
Switch
Terminal board
Installation of chromatograph
3INSTALL.CHP, Stand Dezember 22, 1999
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