WAGO 750 Series User Manual

Fieldbus Communication • 217
ETHERNET
WAGO-I/O-SYSTEM 750
Linux Fieldbus Coupler
10.1.3.4.7 SMTP (Simple Mail Transfer Protocol)
The Simple Mail Transfer Protocol (SMTP) enables sending of ASCII text
messages to mail boxes on TCP/IP hosts in a network. It is therefore used for
sending and receiving e-mails.
The e-mail to be sent is created with a suitable editor and placed in a mail
outbasket.
A send SMTP process polls the out-basket at regular intervals and therefore
finds mail waiting to be sent. It then establishes a TCP/IP connection with the
target host, to which the message is transmitted. The receive SMTP process on
the target host accepts the TCP connection. The message is then transmitted
and finally placed in an in-basket on the target system. SMTP expects the
target system to be online, otherwise no TCP connection can be established.
Since many desktop computers are switched off at the end of the day, it is
impractical to send SMTP mail there. For that reason, in many networks
special SMTP hosts are installed in many networks, which are permanently
switched on to enable distribution of received mail to the desktop computers.
10.1.3.5 Application Protocols
If fieldbus specific application protocols are implemented, then the appropriate
fieldbus specific communication is possible with the respective
coupler/controller. Thus the user is able to have a simple access from the
respective fieldbus on the fieldbus node. There are based on ETHERNET
couplers/controllers available developed by WAGO, with the following
possible application protocols:
• MODBUS TCP (UDP)
• EtherNet/IP
• BACnet
• KNXnet/IP
• PROFINET
• Powerlink
• Sercos III
More information
You can find a list of the exact available implemented protocols in the chapter
"Technical Data" to the fieldbus coupler and/or controller.
If fieldbus specific application protocols are implemented, then these protocols
are individual described in the following chapters.

WAGO 750 Series Specifications

General

Protection Class	IP20
Bus Couplers	PROFIBUS, CANopen, Ethernet
Modules	Digital Input, Digital Output, Analog Input, Analog Output
Mounting	DIN rail mounting
Voltage Supply	24 V DC (typical)
Communication Protocol	Depends on the bus coupler (e.g., PROFIBUS, CANopen, DeviceNet, Ethernet)
Digital Input Channels	Varies by module (e.g., 8, 16 channels)
Digital Output Channels	Varies by module (e.g., 8, 16 channels)
Analog Input Channels	Varies by module (e.g., 2, 4, 8 channels)
Analog Output Channels	1, 2, 4 channels (depending on module)
Width	12 mm, 24 mm (typical module widths)
Number of Channels	Varies by module type
Current Consumption per Channel	Varies by module type