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MPROF... The
reliable rate of flow indicator
INTRODUCTION:
The MPROF Rate of Flow indicator is a
capacitance based solution for reliable
detection of rate of flow of liquids in an open
channel. The level change is measured using the
capacitance principle and converted to rate of
flow utilizing the appropriate formula. The
MPROF system has an interactive user interface
offering you to choose from any of the below
mentioned hydraulic devices:
Cipoletti
Fully Contracted Rectangular
Standard Suppressed Rectangular OR 90° Notch
Triangular Weir or Custom K & N Factor Entry
Once you choose the hydraulic device of your
choice, calculations of the flow rate are
automatically done by the built-in
microcontroller and the value displayed in
percentage (%), cusecs or custom units as per
choice. The system can display the level in % or
in millimeters, if so desired.
A Galvanically isolated 4 to 20 mA analog
output, which can be configured via user
interface to be either proportional to level or
rate of flow, is available. Three relays, whose
function is software configurable, have one
potential free contact each. They can be
configured to either operate as per level change
or as per flow rate change, as desired. All
other functions such as calibration, fail safe
mode selection, switching time delay and delay
modes can be configured via the user interface.
A very stable and noise free signal
communication, using digitally encoded current
pulses, over a simple 2-wire interconnection
between the electronic insert the evaluation
unit, ensures a high degree reliability.
Salient Features:
Microprocessor based system for higher degree
reliability and stable operation in noisy
environment due to intelligent digital
communication between the electronic insert and
the evaluation unit.
All parameters programmable via Five keys and
Five multipurpose LED displays. No potentiometer
settings required.
Galvanically isolated 4 to 20ma output
proportional to either level or flow.
Three relays for programming three levels / flow
independently or as per pump- control logic.
One potential free change over relay output
contact per relay.
Built-in universal power supply for 90 to 260 V
AC or 24V DC operation.
System constants K & N, alarm set points,
Hysteresis, calibration and Display mode
programmable at site. |
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APPLICATIONS:
Suitable for measuring rate of flow of
running water in open channels in filter
stations, water treatment plants,
effluent treatment plants, chemical
plants etc. |
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PRINCIPLE OF
OPERATION:
When the liquid flows through a
Hydraulic measuring device (Weir), the
level of the liquid is directly
proportional to the rate of flow. By
knowing the constants of the Weir, flow
rate can be calculated by the formula:
Q = K * Ln , where Q is
the rate of flow in cubic meters per
hour, L is the level in meters,
k & n are constants that depend
on the Hydraulic device.
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Technical
Specifications: |
Evaluation Unit |
| Housing |
: Cast aluminum, weather proof, stoving enamel painted, suitable for back panel/wall mounting |
| Cable
Entry |
: 3 Nos. ½” BSP / NPT |
| Tolerable ambient temp |
: -200C to +600C |
| Power supply |
: 90 to 260V AC 50Hz, and 24V DC |
| Power consumption |
: 3.5VA (approx.) |
| Utilizable span |
: 10 to 4500 PF |
| Zero setting range |
: 30 to 280 PF |
| Indication range |
: 50% to 150% on multipurpose 5 digit 0.5” LED |
| Accuracy |
: +/- 1% FSD |
| Switching Hysterisis |
: 1% in single point switching and 1 to 98% selectable in 2 point Pump control logic. |
Programming interface |
: 5 Push Button Keys |
| Analog output |
: 4 to 20 ma galvanically isolated into Max 1K Ohm load for 24V DC user supply. Max 800 Ohm for internal isolated supply of 18 to 22 V DC. |
| Output |
: 3 sets of potential free change over contacts rated at 6A, 230V, AC, 50Hz for non-inductive loads |
| Switching delay |
: Programmable up to 99 sec. |
| Fail-safe |
: High/Low field programmable |
| Dimensions |
: 180 x 180 x 85 mm |
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| PRE-AMPLIFIER (electronic insert) LDC117 |
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Housing |
: Plastic with electronics potted, mounted in Probe Head |
| Operating Temp. |
:- 20 to +80 deg. C |
| Supply |
: 18 V DC at 8ma (approx.) derived from evaluation unit |
| Measuring Frequency |
: 250Hz to 20 KHz reverse frequency measurement |
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Probe |
Probe Head |
: Cast Aluminum weather proof |
Mounting Flanged or screwed as per requirement standard
Length 750 to 1500 mm Rigid, with grounding tube as reference and still-well.
Insulation Full PTFE
NB:
1) Reference probe required for non metallic tanks / weirs.
2) Grounding tube required for turbulent liquids.
3) 2-core shielded cable required for electronic insert to Evaluation unit interconnection up to 1
km. (users’ scope). |
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