LumaSense Technologies ISR 12-LO - Handbuch (Seite 10)

IMPAC pyrometers ISR 12-LO · IGAR 12-LO
9
4.2 Connecting the pyrometer to a PC
The pyrometers are equipped with a serial interface RS232 or RS485 (switchable at the pyrometer). Stan-
dard on a PC is the RS232 interface. At this interface one pyrometer can be connected if the interface is set
to RS232. Only short distances can be transmitted with RS232 and electromagnetic interferences can affect
the transmission.
With RS485 the transmission is to a large extend free of problems, long transmission distances can be real-
ized and several pyrometers can be connected in a bus system. If RS485 is not available at the PC, it can be
realized with an external converter which converts the RS485 in RS232 for a standard connection to a PC.
When using a converter RS485
RS232 take care, that the converter is fast enough to receive the pyrome-
ter’s answer to an instruction of the master. Most of the commonly used converters are too slow for fast
measuring equipment. So it is recommended to use the LumaSense converter (order no. 3 852 430).
With a slow RS485 connection it is also possible to set a wait time at the pyrometer which delay the re-
sponse of a command to the pyrometer (see 9.11 Wait time).
4.2.1
Connecting to RS232 interface
The transmission rate (in baud) of the
serial interface is dependent on the length
of the cable. Values between 2400 and
115200 Bd may be set.
The baud rate has to be reduced by 50%
when the transmission distance is dou-
bled (see also 9.9 Baud rate).
Typical cable length for RS232 at 19200
Bd is 7 m.
PC’s side
(soldering side)
K A B
C
D
J
G F E
H M
L 1 2 3 4 5
6 7 8 9
DGND (red)
RxD (black)
TxD (violet)
Pyrometer’s side
(soldering side)
4.2.2
Connecting to RS485 interface
Half-duplex mode:
A1 and A2 as well as B1 and B2 are
bridged in the 12-pin round connector of
the connecting cable, to prevent reflec-
tions due to long stubs. It also safeguards
against the interruption of the RS485 Bus
system should a connecting plug be
pulled out. The master labels mark the
connections on the RS485 converter. The
transmission rate of the serial interface in
Baud (Bd) is dependent on the length of
the cable. Values between 1200 and 115
kBd may be set.
The baud rate is reduced by 50% when the
transmission distance is doubled (see 9.9
Baud rate). Typical cable length for
19200 Bd is 2 km. Terminator 120 Ohm
A
B
S
K A B
C
D
J
G F E
H M
L
K A B
C
D
J
G F E
H M
L
K A B
C
D
J
G F E
H M
L
DG
ND
B1 A2 B2 A1
DG
ND
B1 A2 B2 A1
DG
ND
A2 B2 A1 B1
Master
Pyrometer 32
e.g. address 31
Pyrometer 2
e.g. address 01
Pyrometer 1
e.g. address 00
4.3
Connection of additional analyzing devices
Additional analyzing instruments, for
example a LED digital display in-
strument only needs to be connected
to a power supply and the analog
outputs from the pyrometer. Another
Instruments like a controller or printer
can be connected to the display in
series as shown above (total load of
resistance max. 500 Ohm).
yellow
LED digital display
Controller
Power supply
green
brown
white 230 V ~
24 V DC
°C
Printer