D9412GV2/D7412GV2 | Operation and Installation Guide | 7.0 Telephone Connections
28 Bosch Security Systems, Inc. | 5/05 | F01U003641B
7.5 Phone LED (Red)
The red Phone LED illuminates when the control panel
seizes the telephone line and remains illuminated until
the control panel returns the telephone line. Refer to
Figure 8 on page 27 for the location of the red LED.
7.6 Operation Monitor LED (Green)
The green Operation Monitor LED indicates the
operation of the central processing unit (CPU). When
the CPU is operating normally, the LED flashes 0.5 sec
on, 0.5 sec off.
This green LED also serves as a ring indicator. The
LED is located on the lower right side (Figure 8 on page
27). When there is ring voltage on the telephone line
(the telephone is ringing), the green LED flashes at a
faster rate for the duration of each ring. Ring voltage
must reach a minimum of 45 VAC before the system
detects it.
7.7 Dialing Format
The system can be programmed to use DTMF or pulse
dialing. Refer to Phone Parameters in the
D9412GV2/D7412GV2 Program Entry Guide
(P/N: F01U003636).
7.8 Telephone Line Monitor
The control panel has a built-in telephone line monitor
that tests the telephone line for voltage and current. If
the D928 Dual Phone Line Switcher is used to connect
two telephone lines to the control panel, the control
panel monitors both lines. The normal voltage on a
telephone line is approximately 48 VDC (24 VDC for
some telephone systems). The telephone line monitor
senses trouble if voltage on the line falls to
5.0 to 7.0 VDC without a corresponding 13 mA of
current.
If the monitor senses trouble, it starts a programmable
telephone line trouble timer, which continues to run as
long as the monitor senses trouble. It resets to zero
when the control panel senses a normal line. If the
timer reaches the delay time in the Phone Supervision
program item, it begins a telephone line trouble
response. Programming determines what the response
is. Refer to Phone Parameters in the
D9412GV2/D7412GV2 Program Entry Guide
(P/N: F01U003636).
Any time the control panel uses the telephone line to
make a call or is on-line with the remote programming
software (RPS), it stops monitoring the telephone line
during this process. When the telephone line on the
control panel is no longer in use, it begins to monitor
the telephone line again.
Bad Line Might Test OK: The telephone line monitor
uses voltage levels to test the status of the telephone
line. In some instances, a given telephone line might be
out of service without affecting the voltage on the line.
The telephone line monitor cannot recognize this
trouble condition.
7.9 Called Party Disconnect
Telephone companies provide “called party
disconnect” to allow the called party to terminate a call.
The called party must go on hook (hang up) for a fixed
interval before a dial tone is available for a new call.
This interval varies with telephone company
equipment. Control panel firmware allows for “called
party disconnect” by adding a 35-second, “on hook”
interval to the dial tone detect function. If the control
panel does not detect a dial tone in 7 seconds, it puts
the telephone line on hook for 35 seconds to activate
“called party disconnect,” goes off hook, and begins a
seven-second dial tone detect. If no dial tone is
detected, the control panel dials the number anyway.
Each time the number is dialed, the control panel
records this as an attempt.
7.10 Communication Failure
After two attempts to reach the receiver, the control
panel generates and sends a COMM FAIL PH # event.
The event that triggered the telephone call to the
central station follows the COMM FAIL PH # event.
After ten attempts to reach the receiver, the control
panel enters communication failure. The control panel
clears any reports in its telephone buffer and COMM
FAIL RTE # event is generated, which appears in the
display at keypads. A trouble sounder can be
programmed to annunciate at the keypads.
One hour after the COMM FAIL RTE # is generated,
the control panel attempts to send this event. If the
COMM FAIL RTE # event is the only event in the
queue and cannot reach the central station, the keypads
do not turn on the trouble sounder again.
If the D928 Dual Phone Line Switcher is used, the
control panel makes a total of ten attempts before
entering communication failure.
Enhanced Communication
The D9412GV2 and D7412GV2 Control Panels can
send events over the SDI Bus to a DX4020 or
D9133TTL-E Network Interface Module (NIM). For
more information on the enhanced communications
capabilities, refer to GV2AUX in the
D9412GV2/D7412GV2 Program Entry Guide
(P/N: F01U003636).
