Technical data

188 • Fieldbus Communication
ETHERNET
WAGO-I/O-SYSTEM 750
BACnet/IP Controller
In the case of configuration of network parameters via the DHCP protocol, the
coupler/controller automatically sends a request to a DHCP server after ini-
tialization. If there is no response, the request is sent again after 4 seconds, a
further one after 8 seconds and again after 16 seconds. If all requests remain
unanswered, a blink code is output via the “IO” LED. Transfer of the parame-
ters from the EEPROM is not possible.
Where a lease time is used, the values for the renewing and rebinding time
must also be specified. After the renewing time expires, the coupler/controller
attempts to automatically renew the lease time for its IP address . If this con-
tinually fails up to the rebinding time, the coupler/controller attempts to obtain
a new IP address. The time for the renewing should be about one half of the
lease time. The rebinding time should be about
7
/
8
of the lease time.
4.1.3.3.4 DNS (Domain Name Systems)
The DNS client enables conversion of logical Internet names such as
www.wago.com into the appropriate decimal IP address represented with
separator stops, via a DNS server. Reverse conversion is also possible.
The addresses of the DNS server are configured via DHCP or web-based man-
agement. Up to 2 DNS servers can be specified. The host identification can be
achieved with two functions, an internal host table is not supported.
4.1.3.3.5 SNTP-Client (Simple Network Time Protocol)
The SNTP client is used for synchronization of the time of day between a time
server (NTP and SNTP server Version 3 and 4 are supported) and the clock
module integrated in the (programmable) fieldbus coupler or controller. The
protocol is executed via a UDP port. Only unicast addressing is supported.
Configuration of the SNTP client
The configuration of the SNTP client is performed via the web-based man-
agement system under the “Clock” link. The following parameters must be
set:
Parameter Meaning
Address of the
Time server
The address assignment can be made either over a IP address or a host
name.
Time zone
The time zone relative to GMT (Greenwich Mean time). A range of -
12 to +12 hours is acceptable.
Update Time
The update time indicates the interval in seconds, in which the syn-
chronization with the time server is to take place.
Enable Time
Client
It indicates whether the SNTP Client is to be activated or deactivated.