Kongsberg EM 2040C, Руководство по обслуживанию

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378511/A
1PPS (One pulse per second) using a coax cable
The Processing Unit is equipped with a 1PPS signal input for clock synchronisation.
A Male BNC connector
B Ground
C 1PPS signal
This cable must be provided by the installation
shipyard.
The 1PPS (one pulse per second) signal is normally
provided by a positioning system.
This is an optically isolated connection that requires
approximately 10 mA current. The input power and
the resistor value must be adjusted accordingly.
The 1PPS (one pulse per second) signal is connected to the coax connector on the
CBMF board.
The CBMF board is equipped with an optocoupler at this input. The input series resistor
is tuned for a TTL signal (Low level<0.6 V, High level>3.2V). It can be selected in SIS
wether the falling edge or the rising edge of the signal is used by the Processing Unit to
synchronise the internal clock.
The 1PPS signal must be minimum 1 microsecond long.
Optical isolated input signals
330 Ω
I
F
U =1.2V
F
Trig In+
Trig In-
R
E
CD020104_102_001
A Input from external system
B Processing Unit input
circuitry
The input current must
be approximately 10 mA.
Depending on your input signal
additional resistance must be
applied to achieve the required
input current. Two examples
are shown to clarify.
Example:
I =
F
»
10mA
330
W
4.5V - 1.2V(U )
F
EM 2040C