Operating Procedure, 4184 Watchdog Module; Other Expansion Devices; Model 4140 Intercom/Telephone Controller - Regency 4720 Installation Manual

Regency ® Model 4720 Control/Communicator Installation Manual (P/N 150476, Rev. A)
The Model 4184 Watchdog Module is installed in the Snap-trak, and connects to the Model 4720 control
communicator through a 4-conductor cable (P/N 130235) in the following manner:

Operating Procedure, 4184 Watchdog Module

13.2
If a short or open should develop in touchpad power (Terminal 20 or Fuse F2), the LCD will go blank. The
Model 4184 Watchdog Module will start its audible alarm within two (2) minutes of this event.
If a short or open circuit should develop in the data flow to the touchpads (Terminal 21), the LCD will not
change its displayed information. In this situation, the Control/Communicator will reset the touchpads
within 70 seconds. A single letter will appear, and all LEDs will be turned on. The 4184 Watchdog Module
will start its audible alarm at this moment.
If a short should occur in the data from the touchpads (Terminal 22), the following events will occur. The
Model 4720 Control/Communicator will reset the touchpads every four (4) seconds. This will cause the
LEDs to flash and an audible signal will be heard. The Model 4184 Watchdog Module will not be activated.
If an open condition should occur in the data flow from the touchpads (Terminal 22), the following events
will occur. The Control/Communicator will reset the touchpads within 70 seconds. A single letter will
appear on the touchpads and all LEDs will be on. The audible alarm will beep once. The Model 4184
Watchdog Module will begin emitting its audible alarm within the next two (2) minutes.
If a failure should develop in the control MCU, the Model 4184 Watchdog Module will start emitting its
alarm within two (2) minutes.

Other Expansion Devices

14

Model 4140 Intercom/Telephone Controller

14.1
The Model 4140, when used with Model 4640 Audio Module, is a hands-free telephone and intercom
system. This system operates in a half-duplex mode, meaning that only one party can talk at a time. The
Model 4140 uses complex circuitry to detect when each party is attempting to talk. It then switches the talk
direction to the party meeting the criteria established by the Model 4140.
As a general rule, the party with the highest audio level will have control of the talk path. This is why
hands-free systems, such as the Model 4140, do not function well in high noise environments.
The 4140 must be mounted within three (3) feet of the Model 4720.
Wire Color
Brown 9 (circuit ground)
Red 11, 12, 13, 14 (loop power)
Orange 21 (serial data touchpads)
Yellow 22 (serial data from touchpads)
4720 Terminal
48
Revised 10/98