Seneca Z-PASS1, Руководство пользователя

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USER MANUAL – Z-PASS1/Z-PASS2
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In the above picture, two serial ports (e.g. COM2 and COM4) are configured as Modbus Slave and
connected to a PLC Modbus Master port; so, the two PLCs and the Modbus TCP Client can write/read the Z-
PASS shared memory to share data among them.
The Z-PASS Modbus Gateway provides some interesting features as explained in the following.
Besides “classic” gateway behavior, Tags can be configured to involve in “Bridge” mode, this modality
allows to acquire Tag values from serial side, only when Gateway receives Modbus TCP Request; That can
be very useful when in serial line there are RTU devices with “Fail safe” outputs
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, as explained in details in
18.5.1 paragraph.
Z-PASS Modbus Gateway performs Requests optimization on the RTU side, inserting as many tags as
possible in a single read/write request; the maximum number of registers in a request can be set
independently for each serial port and for read and write operations; this option can be useful to connect
RTU devices which support different maximum number of registers on different serial ports.
Tag configuration can be created using a Microsoft Excel™ Template provided by Seneca (see 18.5.3
paragraph); this can largely reduce configuration time, particularly when a large number of tags shall be
configured.
13 VPN
Z-PASS supports the standard OpenVPN protocol.
The main advantages that come from using a VPN are:

secure connections, since transported data are encrypted;

the ability to establish connections without interfering with the corporate LAN;

no need to have a static/public IP address on the WAN side;

remote configurability by a built-in Web Server.
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This feature is available in many Seneca products.