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SA823
U-NET REPEATER
The SA823 is a signal repeater to extend the range of U-Net two-way wireless technology. It is fully
compatible with any U-Net enabled sensors and controller.
The signal repeater is designed to be installed by a system installer in cases where signal reception is
poor or extended range is required for the home. The repeater does not alter the existing binding
network between gateway and devices, in fact devices do not need to be physically removed from their
mounting location when adding the repeater. This allows the installer to service the user in the shortest
time possible without disrupting to the home interior.
It comes with installer friendly feature such test mode to indicate signal strength using LED display and
audible beeps for areas not in line of sight such as corners. Powered by backup battery, this allows the
repeater to be easily placed anywhere while searching for its optimum location. There is the also a
Beacon mode which allows the installer to conveniently walk around the home to observe signal
strengths from the gateway when deciding on the best location.
Product Overview
Front View
View with Battery Cover removed
Repeater network overview
The role of the Repeater in a U-Net network can be summarized in the diagram below.
Level
:
Repeaters are distinguished into Level-1
and Level-2 as set by their Level jumper
setting. Each pair of Level-1 and 2
repeaters define a unique signal path to
the gateway. Signals from each pair will
not cross over to another pair.
-
Level-1: Repeater closest to the gateway. In most cases adding a Level-1 Repeater is sufficient to
cover a wide range. A gateway can have more than one Level-1 Repeaters to branch out at different
angles from the gateway.
- Level-2: Repeater to extend signal from Level-1 Repeater. Only one Level-2 repeater can be added for
each Level-1 Repeater.
To create the link between the pairs, repeaters must perform U-net binding with each other. Repeaters
with the same level cannot bind with each other.
Lastly, like all end devices under the gateway’s network, each repeater must perform U-net binding with
the gateway. This ensures the gateway is aware of the repeater’s own condition such as low battery,
tamper, etc.
Note: It is advisable to use as few Repeaters as possible in a network in order to reduce signal hops
between device and Gateway. Like any wireless network, more signal hops not only mean longer delay
in transmission but also adds higher risk of signal interference resulting in lost messages as more
devices are added. This degrades the overall network quality.
Join
:
The repeater becomes associated with an end device through ‘Joining’. This is a loose form of binding
that tells a repeater which devices it should repeat signals for and which do not. Joining is a manual
process similar to U-net binding except there is no need to remove end devices from their mounting
position to activate a learn key. Simply trigger the end device for it to transmit its ID which is then picked
up by the repeater. Joining does not disrupt the original U-net binding between end devices with
gateway.
Inversely, a device is disassociated from the Repeater through ‘Un-join’. Removing a device from the
Repeater’s memory helps to reduce unnecessary transmission of RF signal which will improve overall
quality of the network.
LED Table
The table below describes the LED indication at various stages of the unit’s operation.
Pairing stage:
During the Repeater’s pairing activity, Status LED along with the buzzer beeps indicate the status of the
paring.
Status
Status LED
Buzzer Beep
Factory reset state. Repeater not
paired to any Gateway.
After power up, Blinks RED
every 2 secs for 30 secs.
None
Enter pairing mode
Steady RED
Short beeps every 1 sec, followed by
1 long beep
Waiting to bind with gateway, time out
in 30 secs.
Blink RED, every 1 sec
Short beeps every 1 sec
Pairing successful
LED OFF
1 Long beep
Pairing fail after time out or
terminated
Flashes RED 3 times
Short beep 3 times
Joining fail because exceed device
limit
On RED for 1 sec then OFF
3 short beeps
Device Un-join successful
LED OFF
2 Long beep
Level-2 Repeater disconnected
successful
LED OFF
2 Long beep
Activate Factory Reset
Steady RED
Short beeps, followed by 1 long beep
Testing stage (Mode switch set to TEST)
During Test mode, RF LED and the buzzer beeps indicate the signal strength.
RF LED – Test Mode
Buzzer beep sound
Description
Flash GREEN 3 times
Short beep 3 times
Signal is Good, Test mode
Flash ORANGE 2 times
Short beep 2 times
Signal is Normal, Test mode
Flash RED 1 time
Short beep 1 time
Signal is Weak, Test mode
Flash GREEN 3 times
Long beep 3 times
Signal is Good, Beacon mode
Flash ORANGE 2 times
Long beep 2 times
Signal is Normal, Beacon mode
Flash RED 1 time
Long beep 1 time
Signal is Weak, Beacon mode
RF
Stat
Batt
Wall
Rear View
Back
DC
Mode Switch
Tam
p
Buzze
r
Factory
Level Jumper
Learn Button
