Pendulum GPS-12, User Manual, Page: 33 / 62

–
Connect 48 V
DC
to the power D-sub con-
nector with the plus pole to the ground pin
and the minus pole to the pin marked
-48VDC. Use the mating D-sub socket
connector that is included with the
instrument.
–
Check that the instrument behaves in the
same way as when it is connected to line
power only.
–
Reconnect the line power cord, and dis-
connect the 48 V source temporarily.
–
Check that the instrument behaves nor-
mally.
–
Reconnect the 48 V source while the in-
strument is still operating off line power.
–
Check that the instrument behaves nor-
mally.
–
Disconnect the line power cord and check
that the instrument continues to work
without interruption (UPS function).
Option 78 & Option 78/HS
(Int. battery backup & ext. 12 V
DC
)
–
Connect the instrument to line power and
press the
Power/Standby button to enter
Standby mode. The red LED above the
button shall light up.
–
Let the internal battery charge for 3 hours.
Then it will reach about 80 % of its capac-
ity.
Note: It will take another 21 hours for the
battery to reach full capacity if it was
completely discharged from the be-
ginning.
–
Disconnect the power cord and switch on
the instrument.
–
Check that the instrument behaves nor-
mally and is operative for about 90 min-
utes.
n
Option 78/HS only
–
Connect 12 V
DC
to the power D-sub con-
nector with the minus pole to the ground
pin and the plus pole to the pin marked
+12VDC. Use the mating D-sub socket
connector that is included with the instru-
ment.
–
Check that the instrument behaves in the
same way as when it is connected to line
power only.
–
Let the internal battery charge for about
half an hour.
–
Disconnect the 12 V source.
–
Check that the instrument continues to
work without interruption (UPS function).
n
Both Options
–
Reconnect the line power cord.
–
Check that the instrument behaves nor-
mally.
–
Let the internal battery charge for about
half an hour.
–
Disconnect the line power cord and check
that the instrument continues to work
without interruption (UPS function).
Option 79/01
(1 x 1 pps in & 1 x 1 pps out &
2 x 10 MHz out)
n
1 pps In
–
Disconnect the GPS antenna.
–
Connect a stable 1 pps TTL source to the
1 pps input on the option board.
–
Select External 1 pps from the Osc
submenu on the front panel.
–
Return to the main menu.
5-5 Rear Panel I/O
Performance Check