Technical data

Installation & Operation Manual GM-TTT
Page 63
GPS Status:
Two LED’s at the front side of the GM-TTT are directly controlled by the GPS receiver and
provide the following information:
LED free Reception status Received satellites
Continuously lighting No synchronisation was
performed since power-on.
None
Lighting, but shortly
interrupted every five
seconds.
No synchronisation was
performed since power-on.
The number of interruptions
equals the number of
received satellites.
Off, but shortly flashing every
five seconds.
Real-time information was
received, but no reception
possible at present.
No satellite is received, if the
LED flashes four times. Every
flash less corresponds to one
satellite more.
Off In-sync At least four.
LED mod.
Flashing (every second) in case of serial data
transmission.
Serves to check that the GPS
receiver is powered.
The GM-TTT
displays further status data permitting to check the functionability of the receiver,
please refer to chapter “3.8.3 1... 6: Status Data of the Reference Time“.
Operation with the GPS Receiver Installed:
It is recommended to use the following parameters for operation with this reference time:
In the REFER - MODE 1 menu:
Digit 8
Digit 7 Digit 6
Digit 5 Digit 4 Digit 3 Digit 2 Digit 1
, i.e. time and date of the
GPS module are adopted after power-on and periodically once a day. The reference time is
treated as UTC, while the time of the internal clock of the GM-TTT is defined by the para-
meters set in the ZONE submenu (time offsets for normal time and DST).
If the GPS module did not have any reception for a long period of time, so that time and date
are incorrect, manual setting of the GPS module clock is possible. Time and date of the GPS
module are always set, whenever the internal clock of the GM-TTT is set: in the SET - ... - TIME
and SET - ... - DATE menu or by using a control unit of the MTD system, if the GM-TTT is
serving as the central generator of the MTD Time-Timer-Time Code system.