User guide

The most widely used application of the RLH-TG multiplexers is to set up point to point wireless T1/E1
links using low cost wireless LAN bridges. RLH-TG multiplexers can work with most LAN bridges on the
market. It may be necessary to adjust different parameters such as packet size and packet jitter
absorption buffer size for best operation for different LAN bridges.
Be aware that wireless LAN bridges have a very limited bandwidth. If Ethernet data is to be transferred
at the same time, its traffic must be restricted. Otherwise it will affect the T1/E1 packets. Since the LAN
bridges usually don’t have adequate QoS mechanism to guarantee the T1/E1 priority, it is strongly
recommended that the data traffic be routed through the device’s local data port.
Warning
When connecting to a wireless LAN bridge, the uplink Ethernet cable often connects to the outdoor unit,
posing danger to lightning strikes that can seriously damage the equipment. To protect the equipment
as well as people, surge protection devices with good earth connection is strongly recommended. Poor
earth connection may also hinder the operation of the Ethernet port, causing severe packet losses.
Fiber Optic Isolation
PBX/BSC/RNC
RLH-TG-2A-1 RLH-TG-2A-1
FIBER
CABLE
GPR 300V POINT
(GPR ZONE)
N*T1
COPPER
CABLE
FE/GE
HIGH VOLTAGE
TOWER OR
SUBSTATION
BTS/Node-B
Typical HVP Application
Network equipment in high voltage areas can be at risk due to Ground Potential Rise (GPR). In this
instance copper network cable referenced to a remote ground can become a path for high voltages
during a ground fault. Use of all-dielectric fiber optic cable instead of copper completely eliminates the
presence of a remote ground, which dramatically increases safety of personnel and reliability of
equipment. By utilizing GE fiber optic cable, the RLH-TG multiplexer provides absolute electrical
isolation between both ends of the network.
Copper twisted pair Ethernet is limited to 100m/328ft without extenders. Using fiber optic cable
provides long distance service up to 80km/50mi. without any additional equipment. Optical fiber is also
immune to EMI/RF interference, ground loops, and high voltage surges from lightning or ground faults,
and is ideal in electrically noisy environments such as near large power sources, electrical motors, and
radio communications equipment.
General Information! RLH Industries, Inc. - 16 Channel T1/E1 over GE with Fiber! 9