Vertical comdial DX-120, Installation And Maintenance Manual

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I
NSTALLING THE
DX-120
DX-120 Installation and Maintenance Manual
- 66 -
Add a Loud Bell Control or Gate Control
One “dry-connection” is provided at the CPM of the DX-120 system for use with external ringing devices or door
opening apparatus. The DX-120 can be programmed to activate the dry contact whenever certain CO lines ring or
whenever the LBC code is dialed to actuate a door opener.
INSTALLING A LOUD BELL
1) Be sure that the entire system is turned off.
2) Remove the KSU 1 cover (four screws at each corner).
3) Install a static discharge wrist strap on your bare wrist, and adjust it for a snug fit.
CAUTION
Be sure that the strap is touching bare skin and is not isolated by clothing.
4) Connect the wrist strap cord between the wrist strap and an AC or earth ground.
5) Connect a static discharge wrist strap to a suitable earth ground.
CAUTION
Circuit boards are susceptible to damage caused by electrostatic
discharge. You must keep this in mind as you handle the circuit boards.
For additional information, see Vertical publication IMI01-005, Handling of
Electrostatically Sensitive Components.
6) Locate the CPM and “BELL” connector jack on the CPM.
7) Wire the DX-120 BELL contact in series with an external 24vdc power supply and 24vdc bell or
ringing device.
CAUTION
Use only 24v or less voltage supply and Direct Current (dc).
8) Program LBC operation for CO line ringing according to CO line group assignments.
HINT
For more information refer to the DX-120 Technical Manual, Volume II,
Programming.
Add a Loud Bell or Gate Control (continued on next page)
“BELL” control connector (wires to
bell and power supply)