ADCP-50-304 • Issue 19 • June 1999 • Section 4: PatchSwitch X.21

3.4Status Indication Modules

The six X.21 circuit leads having LED indicators are: T, C, R, I, S, and B. When a monitored circuit lead is active (signal present), the associated LED indicator turns on only while the signal is present. The colors and signal definitions for the applicable Led Status indicators shown in Table 4-1.

Table 4-1. Signal Status

ABBREVIATION

SIGNAL NAME/LEAD

LED COLOR

SIGNAL ORIGIN

T

Transmit

Green

DTE

 

 

 

 

C

Control

Green

DTE

 

 

 

 

R

Receive

Red

DCE

 

 

 

 

I

Indication

Red

DCE

 

 

 

 

S

Signal Element Timing

Red

DCE

 

 

 

 

B

Byte Timing

Red

DCE

 

 

 

 

3.5Alarm Modules

Two time-out alarm functions are provided.

Alarm A Monitors the time between the raising of C lead and the raising of the I lead during the call request phase. If this value is greater than the user selected interval, the A alarm LED and/or audible alarm is activated.

Alarm B Monitors the time between the dropping of the I lead and the dropping of the C lead or the dropping of the C lead and the dropping of the I lead, during the call clear phase. If this value is greater than the user selected interval, the B alarm LED and/or audible alarm is activated.

The alarm is indicated by the amber LED and/or an audible alarm located in the chassis. Both alarms have independent variable delays and can be turned off.

The three position toggle switch located on the front panel allows the following choices:

ALM

Visual and Audible alarms on.

OFF

Visual and Audible alarms off.

LED

Visual alarm only.

3.6Alarm Reset

To reset the alarm on the PSM-832002 push the switch marked RST. To reset alarm on all other alarm modules touch the the pads marked RST. If alarm condition has not cleared, the alarm will time-out, and alarm will be tripped again.

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© 1999, ADC Telecommunications, Inc.