Datcon DT9102 I4, Руководство по эксплуатации

Страница: 8 / 64

DT9102 I4
8
20220103-V0
3.2. Principle of operation
Area of application DT9102 I4 is an intrinsically safe digital clock enable
accurate time to be displayed in even the most hazardous
plant areas: Zone 1, 2 or in the safe area.
Synchronising function allows the clock to be synchronised
with a master clock. The clock can be synchronise through
the current loop. When the loop current is over 12 mA the
clock stop going when the loop current decrease under
8 mA the clock will re-start from a new time selected in the
programme menu. This may be the nearest minute or the
nearest hour of the original display or a preset time may be
entered during programming.
The DT9102 I4 has two isolated digital outputs, which can
be used for alarm signaling or for synchronising other
clocks.
DT9102 I4 is housed in a moulded polycarbonate case
hauseproof to IP65 for installation in the field or on the
control panel.
Operating principle The clock incorporate a high accuracy temperature
compensated time base, which is processed by a
microcontroller. The microcontroller produces the real time,
in 24 hour HH:MM format, drives the large 4 digit 25,4 mm
height LCD display, process the front panel keypad, the
synchronising inputs, and drives the digital outputs. The
settings and the actual time are stored in a memory which
stores it’s content for cca. 1 hour for bridging the supply
current failure. The clock also going for cca. 1 hour at this
case.
Power supply DT9102 I4 is loop-powered from 4–20 mA synchronising
signal, dropping less than 2,2 V.
It is not recommended to bring the supply current below 8
mA.