Open Channel / Sewer Portable Flowmeter model PCM4

Open Channel / Sewer Portable Flowmeter

model PCM4

Undoubtedly the most accurate portable flow measurement

The portable PCM 4 is designed for temporary flow measurement over longterm periods in open channel applications such as wastewater collection systems, storm sewer systems, and combined sewer systems. The battery powered system provides high accuracy depth and velocity data. The PCM 4 can be used for many project applications, like

infiltration/inflow analysis and reduction
master plan studies
storm sewer monitoring
suitable for MCERTS testing ...

Some of the most important features for using the PCM 4 even in difficult applications are:

data transmission via Bluetooth
measures the real flow velocity profile
spatial allocation of single velocities
no calibration required
absolutely stable zero point and drift-free
triple redundant level measurement
measurement in all part filled and full pipes and channels
measurement in heavily polluted and abrasive media
multilingual parameter setting in dialog mode
easy operator guidance
also available as PCM Pro, for the use in Ex areas

Measurement principle

The quantity >>flow "Q"<< cannot be measured directly. The following general equation is the basis for flow calculation:

The wetted cross-sectional area A depends on the cross-sectional profile and the flow level. This flow level will be determined by using integrated and / or external sensors. The wetted cross-sectional area will be calculated taking the cross-sectional profile into account.

Flow level measurement

You are free to select between 5 different detection principles depending on your application.

water-ultrasonic integrated in combi sensor [h1, measurement from bottom up]
pressure measurement cell integrated in combi sensor [h2, measurement from bottom up]
wedge sensor with air-ultrasonic [h3, measurement from top down]
variable external level sensor [h4, 4-20 mA]
fixed value at constant fill level

Ultrasonic

In case of water-ultrasonic as well as in case of air-ultrasonic [h1; h3] the flow level will be detected using the echo sounder principle. The interface between water and air (water surface) will be detected in both cases and the sound transit time between sensor and water level will be measured.

The flow level is proportional to the measured time which will be determined as a result from that. This measurement method stands out for its accuracy and long-term stability. Foam or other substances floating on the water surface do not affect the result of the water-ultrasonic measurement.

Hydrostatic

Level measurement is even possible in strongly absorbing media by using a hydrostatic measurement [h2] which can also be integrated into the sensor. The high-resistant Hastelloy diaphragm allows the sensor to be used in heavily contaminated or aggressive media.

By detecting atmospheric pressure and the hydrostatic pressure of the measurement medium simultaneously air pressure fluctuations are ideally compensated.

External sensors

External level sensors with 4-20 mA signals can be integrated into the system without any problems. In case of constant fill levels no additional level sensors are required due to the use of a fixed value.

Flow velocity measurement

An ultrasonic converter (sensor) sends an ultrasonic burst into the medium. The particles or gas bubbles in the medium reflect this impulse. The sensor operates in impulse-echo mode, i.e. the ultrasonic converter will switch to receiving mode immediately after transmitting the burst, receiving the reflected ultrasonic echo as a characteristic echo image pattern.

Transmitter: lightweight

The most important details at a glance:
large back-lit graphic display dialog mode user interface graphic indication of hydraulic conditions at the measurement place numeric and graphic sensor diagnosis protocol function for the most important measurement data logging of current flow measurement values ( Q, h, v, T ) and system parameters	variable measurement modes for cyclic, event-based and continuous measurement with freely selectable storage interval removable data memory (flash card) up to 128 MB for data storage and data transfer to PC operating time per battery charge 40.000 measurement cycles 3 months / 5 minute cycle environmentally acceptable rechargeable battery can be used with standard batteries (size D) alternatively line powered operation possible	recording of pump run times and switching events storage of external analog signals (fill levels, flows, analysis values...) enclosure rating: IP 67 analog output of measured values sampler driving transmission of error messages output of limit values output of volume impulse telemetered communication (pending)
Programming
	Programming the unit is remarkably simple. The user will be guided through the menu thanks to the windows-like program and the dialog mode on the large graphic display. Programmed settings will be clearly indicated graphically. The program structure is perfectly set for the requirements of a portable measurement system. This virtually eliminates any possibility of faulty programming. As standard, access can be restricted in order to prevent the unit from unauthorised modification.	Display
		The back-lit display can be clearly read even in dark shafts and manholes. It enables the user to easily program the unit as well as to simply recall sensor data, echo profiles, velocity distributions, historical trend graphs... Direct flow profile indication on the display

Specifications


Transmitter		Sensors
Power supply	12 V DC, 12 Ah rechargeable lead battery or battery box for 12 x mono cells 1.5 V (type LR20), power pack 100 - 240 V AC, 50/60 Hz	Measurement principle	ultrasonic transit time (level/height) piezoresistive pressure meas. (level/height) correlation with digital pattern detection (flow velocity)
Enclosure	Material: Polypropylene (PP), shock-resistant Weight: approx. 2.0 kg (without sensor and rechargeable battery)	Measurement range (v)	-1 m/s to +6 m/s
Protection	IP 67 if lid is closed and locked	Measurement range (h)	pressure 3.5 m; ultrasonic 2 m
Operating temperature	-20 °C to +50 °C	Measurement frequency	1 MHz
Storage temperature	-30 °C to +70 °C	Protection	IP 68
Max. humidity	90%, non-condensing	Operating temperature	-20 °C to +50 °C
Display	back-lit graphic display, 128 x 128 pixel	Storing temperature	-30 °C to +70 °C
Operation	18 button keypad or alternatively via Bluetooth, multilingual dialog mode	Measurement uncertainty	deviation less than 1 %, (under given specific conditions)
Plug-in socket IP 68	1 x 4-20 mA for external level (2-wire probe, active) or 1 x active air-ultrasonic for level measurement 1 x active water-ultrasonic/pressure combi sensor for velocity and level measurement 1 x multifunctional socket for digital and analog inputs and outputs 1 x connection socket for combined power supply and charger unit or alternative power supply 1 x Bluetooth for data transmission	Operational pressure	max. 4 bar (combi sensor with pressure measurement cell max. 1 bar)
Inputs via multifunctional socket	1 x active digital input, supply voltage 3.3 V DC 1 x analog input 0/4-20 mA (passive)	Cable length	max. 100 m, in case of using sensors with pressure measurement after 30 m a pressure compensation element is required
Outputs via multifunctional socket	1 x relay (SPDT) contact rating: 250 V AC, 5 A / 30 V DC, 5 A switching frequency: 5 Hz 1 x voltage output	Sensor types	V100 flow velocity sensor (v; temperature) V1H1 combi sensor (v meas., level meas. using water-ultrasound and temperature measurement) V1D0 combi sensor (v meas., level meas. using pressure and temperature measurement) V1U1 combi sensor (v meas., level meas. using water-ultrasound and redundancy using pressure and temperature measurement)
Storage cycle	1 to 60 minutes, time-cyclical or depending on events	Constructions	wedge sensor for installation on channel bottom
Data storage	external, on plug-in compact flash card up to 128 MB capacity; internal RAM with 8 MB	Materials	Polyurethane, stainless steel 1.4571, PPO GF30, PA
Data storage		Option	PEEK, Hastelloy C276 ground plate, Titanium ground plate;
Data transmission	via pluggable compact flash card and/or Bluetooth	Accessories	Bluetooth modem (antenna), compact flash card, card reader, adapter, pipe mounting system, suspension bracket, etc.