PTT24 Manual
Chapter 3
Testing
Overview
The PTT24 has a front panel test switch, Channel Selector Switch for the Guard Channel,
Audible Alarm, and LEDs. The PTT24 has rear panel Alarm IN and Alarm OUT connectors.
The PTT24 has an internal RS232 test port. A factory test assembly is used during
manufacturing for final testing of the PTT24. Most of the PTT24 functionality can be checked
in the field. The following outlines the testing that can be done in the field. The factory test
procedures are also noted. The factory test assembly can be purchased for customer field use.
Field Testing
Front Panel Test Switch
Pressing the front panel test switch will enable all the relays, sound the audible alarm, light
the Alarm LED, cause the Alarm Out leads to close and all the relays will operate. The
sound of the relays operating can be heard as a low level clicking sound. The alarm will
sound only when the ALARM toggle switch is in the ON position.
Alarm In and Alarm Out
To test the Alarm In, the 2 leads on the Alarm In connector can be shorted together. When
shorted, the ALARM LED will light, the audible alarm will sound (if not disabled by the front
panel switch) and all the relays will operate. The Alarm Out can be checked with a VOM.
When the the Relay Test button is pushed the Alarm Out leads will be closed.
Channel Selector Switch and Power LED
The channel selector switch can be set to an invalid channel number. This will cause the
Power LED to flash.
Audible Alarm
With the Alarm Cutoff Switch set to ON, pressing the Test Switch will cause the audible
alarm to sound. Also, shorting the Alarm In leads will cause the audible alarm to sound. If
the alarm is activated with the Alarm Cutoff Switch set to OFF, no audible alarm will sound.
LEDs
The LEDs are Power/Invalid Channel, ACO and Alarm. The Power LED is on when power is
applied to the PTT24. The Power LED will flash if an invalid control channel is selected. An
invalid channel is any except 1 through 12 when 12 channels are selected via the front panel
switch. An invalid channel is any except 1 through 24 when the 24 channels are selected via
the front panel switch.
RS232 Port
The PTT24 has an internal RS232 port located on the right hand side of the PC board when
viewed from the front. To access the RS232 port the cover of the PTT24 must be removed.
The RS232 port is an RJ45 connector. A special Network Management cable and RJ45 to
DE-9 female connector is available for using this RS232 port. See the next section for details
on the operation of the RS232 port.
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