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SERIAL INTERFACE
RS-485 interface allows to connect up to 30
devices with one remote master unit.
Fig. 11 - RS-485 WIRING
The cable length must not exceed 1.5 km at 9600
BAUD.
NOTE
: The following report describes the signal
sense of the voltage appearing across the
interconnection cable as defined by EIA for
RS-485.
a) The ” A ” terminal of the generator shall
be negative with respect to the ” B ”
terminal for a binary 1 (MARK or OFF)
state.
b) The ” A ” terminal of the generator shall
be positive with respect to the ” B ”
terminal for a binary 0 (SPACE or ON)
state.
D) POWER LINE WIRING
Fig. 12 POWER LINE WIRING
NOTES
:
1) Before connecting the instrument to the power
line, make sure that line voltage corresponds to
the description on the identification label.
2) To avoid electrical shock, connect power line at
the end of the wiring procedure.
3) For supply connections use No 16 AWG or larger
wires rated for at last 75 °C.
4) Use copper conductors only.
5) Don’t run input wires together with power cables.
6) For 24 V DC the polarity is a do not care condition.
7) The power supply input is
NOT
fuse protected.
Please, provide it externally.
Power supply
Type
Current
Voltage
24 V AC/DC
T
500 mA
250 V
100/240 V AC
T
125 mA
250 V
When fuse is damaged, it is advisable to verify
the power supply circuit, so that it is necessary to
send back the instrument to your supplier.
8) The safety requirements for Permanently Con-
nected Equipment say:
- a switch or circuit-breaker shall be included in
the building installation;
- It shall be in close proximity to the equipment
and within easy reach of the operator;
- it shall be marked as the disconnecting device
for the equipment.
12
13
COMMON
11
B'/B
B/B'
A/A'
A'/A
M
A
S
T
E
R
I
N
S
T
R
U
M
E
N
T
5
R (S,T)
R (S,T)
N
4
N
POWER LINE 100 V to 240 V A.C
(50/60Hz)
or 24 V AC/DC
1604-7-1-AB.p65
5/16/00, 10:50 AM
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