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Release 2 Updates - Feb. 2012
The 1825 Duet Plus ringer has been updated for
2012. All features of the original Duet Plus are
maintained and the same inputs and outputs are
provided. The following lists the most important
changes affecting installers:
AUDIO
INPUT
The audio input still functions as before for dry
paging input and audio detection for loud ring
with heritage Nortel telephones. However, the
input is now rated to carry DC current up to 65
mA and may be connected directly to an Avaya
IP Office FXS port for “wet” paging. Also, if the J2
shunt is not set to PAG then the amplifier is dis-
abled, except when ringing. The shunt position is
checked each time ringing is initiated. The audio
input is not intended to be connected to CO lines
or wiring leaving a building.
TEL TIP &
RING
The input from a telephone CO line or FXS port
has been moved from the internal terminal block
to an internal RJ11 jack. If the Duet Plus is used
in an application involving telephone ring detect
then a safety approved (CSA, UL, CE, A-Tick)
modular cable will be required for connection (not
supplied).
POWER
SUPPLY
The power supply provided with the Duet Plus is
now a regulated high efficiency 24V switch mode
power supply with energy level V compliance.
LED
INDICATORS
Two LEDs are now located on the PCB. A green
LED indicates power and a red LED indicates
power limiting. These are to help installers
and Algo’s support team in the event that any
troubleshooting is required. If an over-current
condition is detected then the 1825 automatically
reduces audio level to maintain current at a safe
operating level.
