Nautel XL12 Technical Instructions Download Page 123

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12 000 WATT AM BROADCAST TRANSMITTER

XL12

Page 6-10

01 January 2002

6.6.14.6

Internal Interlock Alarm:

The

Internal Interlock Alarm

output is applied to the

remote interface PWB's

INT INTLK ALARM

terminal.

When the interlock circuit is intact, the output is an
open collector. When the interlock is open, the

Internal Interlock Alarm

output will be a current-

sink-to-ground. The RF output will be turned off by
removing 24 VDC from the transmitter's control
circuits.

6.6.14.7

External Interlock Alarm:

The

External Interlock Alarm

output is applied to the

remote interface PWB's

EXT INTLK ALARM

terminal.

When the interlock circuit is intact, the output is an
open collector. When the interlock is open, the

External Interlock Alarm

output will be a current-

sink-to-ground. The RF output will be turned off by
removing 24 VDC from the transmitter's control
circuits.

6.6.14.8 Filter Temperature Alarm:

The

Filter

Temperature Alarm

output is applied to the remote

interface PWB's

ALARM - FILTER TEMP

. When the

output filter's temperature exceeds the maximum
ambient temperature of 85

C, the output will become

a current-sink-to-ground.

6.6.14.9

Power Supply Temperature

Alarm:

The

Power Supply Temperature Alarm

Alarm output is applied to the remote interface
PWB's

ALARM - P/S TEMP

When the temperature in

the power supply exceeds the maximum ambient
temperature of 85

C, or the power supply's B+

charge/discharge cycle exceeds its allowable period,
the output will become a current-sink-to-ground.

6.6.14.10 Power Module Alarm:

The

Power

Module Alarm

output is applied to the remote

interface PWB's

ALARM - PWR MOD

. It is triggered

by either a PA or modulator failing.

6.6.14.11 Power Supply Alarm:

The

Power

Supply Alarm

output is applied to the remote

interface PWB's

ALARM - PWR SUPPLY

. It becomes

a current-sink-to-ground when there is a B+ voltage
rectifier failure or when a B+ voltage supply
becomes more than ten percent of the ideal voltage
for the power transformer's selected primary winding
taps.

6.6.14.12 Modulation Protection Alarm:

The

Modulation Protection Alarm

output is applied to

the remote interface PWB's

ALARM - MOD PROTECT

It becomes a current sink-to-ground when the level
of audio has exceeded a maximum value-time
product.

6.6.14.13 PDM Inhibit Alarm:

The

PDM Inhibit

Alarm

output is applied to the remote interface

PWB's

ALARM - PWM INHIBIT

. This alarm is

triggered manually when the PDM Inhibit function
has been accessed during repair or maintenance.

6.6.14.14 Standby Alarm:

The

Standby Alarm

output is applied to the remote interface PWB's

ALARM - STANDBY

. This alarm is triggered (output

becomes a current sink-to-ground) when there has
been an automatic transfer from the main transmitter
to the standby transmitter.

6.6.15 REMOTE STATUS INDICATIONS:

Outputs that indicate status of operator controlled
circuits are available at terminals of TB2 on the
remote interface PWB. These outputs are provided
for external monitoring. Each status output contains
a switching transistor that provides an open collector
when its circuit is passive (not-true condition exists)
and a current-sink-to-ground when a true (circuit
active) condition exists. Each external monitoring
circuit must present an impedance, between the
switching transistor and a positive DC voltage
source, that will result in not more than 40
milliamperes flowing through the transistor when
turned on. Each status circuit's positive voltage
source must not exceed 24 VDC. Each status
output is protected against transients and/or over
voltage by a 39 volt zener diode.

6.6.15.1

Remote Status:

The

Remote

Status

output is applied to the remote interface

PWB's

REMOTE STATUS

terminal. When transmitter's

CONTROL

switch is set to

LOCAL