Figure 6: Typical wiring of the RS-485 communication line terminals in SMC 133 .
USB (optional)
communication port for USB slave is located on the front panel. This communication port is
intended for easy local configuration and fast download of archived data to the local PC. Use the supplied USB
cable only (USB-A/mini). SMC 133 is a USB 2.0 slave device. For correct operation it needs a driver installed
in your operating system (see the ENVIS user guide for more info).
2.3.5
Inputs and outputs
Instrument provides two separate universal I/O ports with terminals C1, D1 and C2, D2. Each DI/O port can
be used individually as an input or an output function. For a correct operation of the I/O it is necessary to use
an external power supply with nominal voltage 12 to 24 VDC. Appropriate polarity of supply voltage for input
resp. output function must be kept.
Warning! Digital I/Os are unipolar. Right polarity must be kept for a proper operation of the terminal.
Incorrectly connected external power supply can damage the instrument.
DI/O as a digital input DI
is connected to the selected I/O terminal (D1 or D2) and a common terminal (C1
or C2) with external power supply in the following way: the current flows from positive terminal of the supply
through the external input contact to a DI terminal (D1 or D2) and than from the common terminal (C1 or C2)
back to the negative terminal of the external power supply.
DI/O as a digital output DO
is connected to the selected I/O terminal (D1 or D2) and a common terminal (C1
or C2) with external power supply in the following way: the current flows from positive terminal of the supply to
the C1 or C2 terminal and from a DI terminal (D1 or D2) through the controlled load to the negative terminal
of the supply. If an I/O port is used as an output (its behavior is controlled by an internal logic function) the
instrument also indicates its activation with the respective input register.
2.4
Downloading data to PC
Connect the instrument to the PC and run ENVIS.Daq application. Select the appropriate communication
option and connect to the instrument. In the next screen press
Refresh All
. This will load and display the actual
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