DayTronic 3500 Series, Instruction Manual

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2.10 2.b RS-232 (“S
INGLE
-N
ODE
”) C
ONNECTIONS
2
S
ETUP
: C
ONNECTIONS AND
P
OWERUP
line from Pin 4—or the optional external SHUNT RESISTOR line from Pin 5—is tied
to the +SIGNAL line at the transducer. Note the wire connected to the –SIGNAL
line at the transducer, but left unconnected at the instrument. This wire is to be
paired with the CAL SENSE or SHUNT RESISTOR line for shielding purposes.
Special 8-wire cabling (shown in Fig. 11(d)) is required for connecting the 3578 to
a
Lebow 1600 Series Transducer . The cable should be shielded in four pairs,
as shown in the figure, with the shield open at the transducer end. Also note that
• SENSE and EXCITATION lines should be tied at the transducer.
• The conditioner's Pin 5 ("LEBOW CAL") is to be connected to the "CAL" pin on
the Lebow sensor (Pin 4 is not used in this case).
• You should leave the last (extra) wire unconnected at both ends, and pair it
with the "LEBOW CAL" line for the fourth shield.
• THE MODEL 3578 MUST BE INTERNALLY SET TO "SIGNAL COMMON"
MODE. CONTACT THE FACTORY FOR PRECISE INSTRUCTIONS.
2.b
RS-232 (“S
INGLE
-N
ODE
”) C
ONNECTIONS
You should set the RS-232/485 Interface Port for RS-232 operation when you
want your 3500 Series instrument to communicate with a single computer, termi-
nal, buffered printer, or other RS-232-C device. To do so, you need only MAKE
SURE THAT THE INSTRUMENT'S CURRENT NODE NUMBER IS "0" (ZERO). You
will be shown in Section 3.a.3 how to set the node number and other necessary
RS-232 communications parameters via the front-panel buttons.
If you did not order a specific RS-232-C Interface Cable with your 3500 Series
instrument, you will have to provide your own connection. Fig. 12 shows suggest-
ed cabling between the instrument and a computer, terminal, printer, etc., that
uses a 25-Pin RS-232-C Connector. FOR MAXIMUM DATA-TRANSFER SPEED
AND ACCURACY, A "FULL HANDSHAKE" INTERCONNECTION IS GENERALLY
RECOMMENDED (Fig. 12(a)). However, cabling is also given for "INCOMING
HANDSHAKE ONLY" and "NO HANDSHAKE" situations (Figs. 12(b) and 12(c),
respectively). Following RS-232-C conventions, the device at each end of the
interface is seen as "DATA TERMINAL EQUIPMENT (DTE)."
Fig. 13 shows suggested cabling between a 3500 Series instrument and a com-
puter, terminal, printer, etc., that uses a 9-Pin D-Subminiature Connector for its RS-
232-C interface (such as an IBM PC/AT).
Please note that the cabling in Figs. 12 and 13 is by no means definitive. In all
cases, you should carefully study the literature accompanying the specific RS-
232-C device you wish to connect to your instrument, to determine the cable
arrangement that will create the "handshake" you need (if any). On some devices,
for example, the
DATA TERMINAL READY (DTR) signal may have a different
name (such as NOT BUSY ) and may even appear on a pin other than No. 20 or
No. 4.