D7212G
Telephone Connections
6.11Ground Start
Some telephone systems require a momentary ground input to initiate dial tone. To interface with a ground start system, insert a D136
Ground start is not for use in NFPA applications. You cannot use ground start telephone systems for NFPA Central Station Protective Signaling or Remote Station applications.
WARNING
Note: | Terminal 10 must be connected to an earth ground in order for ground start phone systems to operate properly on the |
| D7212G. |
6.11.1Relay Installation
Power down the system before inserting the D136 relay into the GND START socket. The relay socket is in the lower left corner as shown in Figure 7 on page 30. The
Don’t rely on relay labeling: Don’t rely on the labelling to install D136 relays. Check for the side with three pins. The three pins go on the top side on the socket.
Incorrect insertion does not damage the relay or the panel, however the related circuits do not function properly. A ground start relay must not be inserted if the ground start jumper is in the loop start position (see Figure 10).
6.11.2Phone Monitor Select Jumper
The Phone Monitor Select jumper is above the TELCO connector point at the lower left corner of the panel. Set it in the ground start position. See Figure 10.
| GROUND FAULT DETECT |
| Enabled |
| Disabled |
| PHONE MONITOR SELE |
| LOOP |
| GND |
| GROUND START |
| Requires |
Loop Start | Relay Model |
D136 in Ground | |
Start Socket | |
Position |
|
Ground Start |
|
Position |
|
Figure 10: Phone Monitor Select
D7212G Operation and Installation Guide
© 2003 Bosch Security Systems | Page 33 | 4998138544C |