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Line Requirements
The SLSS works with loop start telephone circuits and devices, not with ground
start. (Most telephone circuits and devices are loop start.) Please check with your
telephone company if you are uncertain about your telephone circuit.
Alarm LED
The red LED on the SLSS front panel lights during an alarm condition, such as
watchdog failure, checksum failure, or port timeout. As soon as the problem is
solved, the alarm LED turns off. (The internal alarm relay, which is normally open,
is wired to A1 and A2 on the rear panel. It will close during alarm conditions, and
the Alarm LED will turn on. As soon as the condition clears, the Alarm LED will
turn off and the relay will open.)
Compatibility
Any device that can be connected to a standard loop start telephone line,
including telephones, modems, and fax machines, is compatible with the SLSS.
The Call Waiting and Caller ID features offered by some telephone systems do
not work with the SLSS.
LED Indicators
Lights (LEDs) on the front of the SLSS tell you the status of the unit and ports.
For example, the LED blinks quickly when a call is ringing a port. Unique blinking
patterns indicate different functions, as shown in Table 1.
Table 1 LED Indicators on the SLSS
LED Operation
Status LED
Port Status
LEDs
Slow blink, full to half
brightness
Idle, working properly
—
Fast blink, full to half brightness
Incoming call is ringing SLSS
Ringing port
Slow blink, on/off
In use: SLSS is off-hook toward line
Timeout alarm
Steady on
Power present, but unit not functioning
properly
Port in use
(off-hook)
Off
No power
Idle
Power
In case of power loss, the SLSS will maintain a direct path between the Telco Line
Port and Port 1.
Auxiliary Relay
The relay is only available on models M-395/396-B, D,& E. The relay can be
opened, closed, or pulsed when its functionality is enabled. It may be used to
reset or to cycle power to a modem or other microprocessor-controlled device.
Substation Line Sharing Switch
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