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System Configuration
T801-4 Installation and Operation Manual
© Tait Electronics Limited September 2007
System Alarms
When a system alarm has been received, indicating that the 1PPS signal has
become invalid, you should visit and examine the site or system. One or
both of the RSU GPS receivers has failed in some way. The
GPS SELECTED
LED indicators on the rear panel will also indicate which receiver is selected:
■
PORT A
LED on = secondary RSU GPS selected
■
INT/PORT B
LED on = primary RSU GPS selected.
The
1PPS VALID
LED will be off, indicating that at least one of the 1PPS
signals has become invalid.
If necessary you can use DIP switch 2 to reset the T801-4 to the primary
GPS receiver without powering down the unit. Once the failed GPS system
has been restored, toggle DIP switch 2 to select whichever receiver is
required to be primary.
