Bosch D9412GV2 User Manual

Page of 74
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).