Bosch Appliances D7212G manual 6.11Ground Start, Telephone Connections, Loop Start, Position

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 Plug-in Relay into the GND START socket and set the Phone Monitor Select jumper to the GND START position.

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 plug-in relay is shorter than the socket it plugs into. It can be installed in either the left or right end of the socket.

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

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