Installation
3886_en_A
PHOENIX CONTACT
13
2.3.4
Connecting the Ethernet cable
The GW PN/ASCII... has an Ethernet interface on the front in RJ45 format, to which only
twisted-pair cables with an impedance of 100
Ω
can be connected. The data transmission
rate is either 10 or 100 Mbps. The GW PN/ASCII... supports the auto negotiation function
for automatic selection of the transmission speed, as well as an automatic crossover feature
for the selection of line or crossover cabling.
Push the Ethernet cable with the crimped RJ45 connector into the GW PN/ASCII... until it
engages with a click.
2.3.4.1
Models with two Ethernet ports
When using two Ethernet ports, the GW PN/ASCII... is classified as a switch. When using
only one port, it is a simple end node device. The maximum number of daisy-chained
GW PN/ASCII... units, and the maximum distance between units, is based on the Ethernet
standards, and is determined by the environment and conformity of the network to these
standards. There may be some performance degradation on the devices at the end of the
chain, so it is recommended to overload and test for performance in the environment. The
application may also limit the total number of ports that may be installed. Some basic
guidelines are listed below.
–
Ethernet 10BASE-T rules
–
The maximum number of repeater segments is four.
–
Use Category 3 or 5 twisted-pair 10BASE-T cables. The maximum length of each
cable is 100 m (328 ft.).
–
Fast Ethernet 100BASE-TX rules
–
The maximum number of repeater segments is two (for a Class II hub). A Class II
hub can be connected directly to one other Class II Fast Ethernet hub. A Class I hub
cannot be connected directly to another Fast Ethernet hub.
–
Category 5 twisted-pair cable must be used. The maximum length of each twisted-
pair cable is 100 m (328 ft.).
–
The total length of twisted-pair cabling (across directly connected hubs) must not
exceed 205 m (672 ft.).
–
IEEE 802.3 specification: A network using repeaters between communicating stations
(PCs) is subject to the 5-4-3 rule of repeater placement on the network:
–
The maximum number of segments connected on a network is five.
–
Four repeaters is the maximum that can be applied to a network.
–
Only three segments can have user connections. The other two segments must act
as repeaters with no user connections.
