FIEDLER H1, Руководство пользователя

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Hydro Logger H1 User manual
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electronics for ecology
FIEDLER
4.4.3. Pulse-binary inputs PV1 to PV4
HydroLogger H1 contains 2 fast pulse inputs labeled PV1, PV2 (terminals 16 and
19) and two slow pulse-binary inputs labeled PV3, PV4 (terminals 21 and 23).
All pulse inputs are activated by their connection to the GND ground terminal
and therefore the connected sensors must have either an open collector or a
potential-free contact (relay contact) at the output. At rest, the voltage at the
pulse input is 3.3V. When the input is switched on, the input circuit draws a
current of 30
µA from the power supply battery and therefore it is advisable not
to connect the input to the GND ground terminal in the quiescent state to avoid
unnecessarily discharging the instrument battery (short pulses are optimal).
FAST PULSE INPUTS PV1, PV2
The two fast inputs PV1 and PV2 are
primarily designed for reading fast
and short pulses from sensors and
meters. The minimum pulse length
must be at least 10 mS for inputs
PV1, PV2 and it follows that sensors
with a maximum output frequency
of 50 pulses/sec can be connected to
these inputs.
The outputs of water meter speed
sensors are usually connected to the
fast pulse inputs PV1 or PV2. These
sensors can be of the OPTO, REED or
CYBLE type.
Each fast pulse input is assigned its
own pulse counter. Each time the set
archiving interval expires, the coun-
ter contents are stored in the instru-
ment's internal data memory. The
number of pulses read during one
archiving interval must therefore not
exceed 65,530 pulses, otherwise
they will be lost (not all incoming
pulses will be saved). Since the typical archiving interval is usually 10 or 15 mi-
nutes, the connected OPTO sensor would have to generate more than 70 pulses
per second to reach this ceiling.
CALCULATION AND DISPLAY OF INSTANTANEOUS FLOW RATE
The Hydro Logger H1 continuously calculates the instantaneous flow rate from
the pulse weight (a parameter expressed in litres per pulse) and the frequency
of pulses. The instantaneous flow rate is displayed on the instrument display in
cyclic mode.
Exceeding the instantaneous flow rate above the set limit may trigger a warning
SMS message.
P u l s e i n p u t
c o u n t e r s
Installing the CYBLE sensor on the
water meter