V
O
=24V
V
O
=24V
SMC 144
Power Analyzer
ETH
N
L1
L2
L3
L4
l1 k1 l2 k2 l3 k3 l4 k4
X1
X2
O-
O+
R A1 A2 G B
A
G B/1 A/2
COM1
COM2 / DI
USB
RS-485
PC
PE
Figure 8: An usage example of digital I/Os.
final points of the communication line have to be fitted with terminating resistance.
M-Bus interface (optional)
M-Bus communication interface is intended for remote reading of gas or electricity meters. M-Bus interface uses
terminals
A/2
and
B/1
of
COM2/DI
block. Connection polarity is unimportant.
Digital Output (optional)
Digital outputs are implemented as optional relay switch or impulse output connected through terminals
O+
and
O-
. In case of relay switch, polarity is not important, but when an semiconductor impulse output is used,
polarity of external voltage source must comply with terminal labels and example picture. There is an external
relay controlled by digital output in picture 8. Again, there must be external voltage source in series. When
impulse output is used, direct current voltage source of 24 V is recommended. In case of relay output, nominal
voltage of up to 230 V
AC
can be used.
Ethernet interface (optional)
Optional 10Base-T ethernet interface with RJ-45 connector described
ETH
is situated on a top panel of the
device. Ethernet interface can be used as substitution for the primary RS-485 for connection of the device to
LAN and for easy connection of portable computer for archive download.
2.4
Transferring Measured Data to PC
As with setting phase the device should be first connected to the computer where the program ENVIS.Daq runs.
Select the appropriate port, baud rate, address and press the
Connect
button. Next, press the button
Refresh
All
. This will load and display the actual status of each archive:
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