LumaSense Technologies IS 50-LO plus - Manual (Page 14)

IS 50-LO plus / IGA 50-LO plus Manual Controls and Installation 14
3) hold function: when the hold function mode is activated the current temperature reading is
frozen as long as J and pin K are connected (see 5.3 Clear time for the maximum value
storage).
3.1.2 Connecting the pyrometer to a PC
The pyrometers are equipped with a serial interface RS232 or RS485 (switchable at the
pyrometer). Only one pyrometer can be connected on the standard PC RS232 interface. Only
short distances can be transmitted with RS232 and electromagnetic interferences can affect the
transmission.
The pyrometer is equipped with an RS485 serial interface. With the RS485, long transmission
distances can be realized and the transmission is, to a large extent, free of problems. The RS485
also allows several pyrometers to be connected in a bus system.
If an RS485 connection is not available at the PC, it can be accomplished using an RS485 or RS232
to USB connector. When using a RS485 to USB adapter, make sure that the adapter is fast
enough to receive the pyrometer’s answer to an instruction of the master. Most of the
commonly used adapters are too slow for fast measuring equipment, so it is recommended to
use the RS485
USB converter “USB nano“ (ref. no. 3 852 600).
With a slow RS485 connection it is also possible to set a wait time at the pyrometer which delay
the response of a command to the pyrometer (see 5.9 Wait time tw).
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 doubled
(see also 5.7 kBaud (baud rate)).
Typical cable length for RS232 at 19200 Bd is
7 m.
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 reflections 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 2400 and
115200 Bd may be set.
The baud rate is reduced by 50% when the transmission distance is doubled (see 5.7 Baud Rate
(kBaud)). Typical cable length for 19200 Bd is 2 km.
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)
cable
PC’s side
(soldering side)
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
D
G
N
D
B
1
A
2
B
2
A
1
D
G
N
D
B
1
A
2
B
2
A
1
D
G
N
D
A
2
B
2
A
1
B
1
Master
Pyrometer 32
e.g. address 31
Pyrometer 2
e.g. address 01
Pyrometer 1
e.g. address 00