does anyone have any concepts on detecting waterpump operation(flow)in a non contact manner(led, laser,etc)

 

Is it an electric pump? If so, there are many ways to detect when it is being powered. If not, is it just water flowing through a pipe, and can you sacrifice a little of it's speed? More info would be nice here.

 

A Google of "non invasive water flow sensors" or "clamp on flow sensors" will get you some hits. Many are using ultrasonic and many are not exactly inexpensive depending on exactly what you want and the uncertainty you want. Do you want a simple flow switch or a sensor to measure flow? What range? Clean water or water with solids? All of that matters. You can also as mentioned detect when a pump is running by sensing current but that won't tell you if there is actual flow. All depends on exactly, in some detail, what you want or need?

Ron

 

power to a pump would be nice but would not detect blockage. and power could be supplied via mechanical means(engine). solids would not likely unless micro organisms would count. Marine cooling system applications. is my goal. in current detection( wheels, hall effect, vanes) are all mechanical and do- able. non invasive would be an improvement.

 

Marine cooling system applications. is my goal.

With that in mind monitoring pump power won't necessarily let you know about a blocked line or broken impeller, not simply anyway. Since you don't want to open a pipe and insert a sensor that gets thigs down to as I mentioned earlier, along the lines of a ultra sonic non intrusive clamp on device. Tey come in switch versions working off a large window of power needs including DC shipboard power. Omega Engineering makes them and a host of other manufacturers.

DESCRIPTION

FDT-40 Series ultrasonic flow and energy meters clamp on to the outside of pipes and do not come in contact with the internal liquid. The technology has inherent advantages over alternate devices including: low-cost installation, no pressure head loss, no moving parts to maintain or replace, no fluid compatibility issue, and a large, bi-directional measuring range that ensures reliable readings even at very low and high flow rates. FDT-40 Series is available in a variety of configurations that permit the user to select a meter with features suitable to meet particular application requirements.

Specifications
System
Liquid Types: Most clean liquids or liquids containing small amounts of suspended solids or gas bubbles
Velocity Range: Bi-directional to greater than 40 FPS (12 MPS)
Flow Accuracy:
Larger Than 50 mm (2"): ±1% of reading or ±0.01 FPS (0.003 MPS), whichever is greater
25 to 50 mm (1 to 2"): ±1% of reading or ±0.04 FPS (0.012 MPS), whichever is greater
¾" (19 mm) and Smaller: ±1% of full scale
Sensitivity Flow: 0.001 FPS (0.0003 MPS)
Repeatability: 0.5% of reading
Transmitter
Power Requirements (AC): 95 to 264 Vac 47 to 63 Hz @ 17 VA maximum standard, 20 to 28 Vac 47 to 63 Hz @ 0.35 A maximum (“-24VAC” models), 10 to 28 Vdc @ 5 W maximum (“-VDC” models)
Protection: Auto resettable fuse, reverse polarity and transient suppression
Display: Two line LCD, LED backlit; top row 18 mm (0.7") height, 7-segment; bottom row 9 mm (0.35") height, 14-segment
Icons: RUN, PROGRAM, RELAY1, RELAY2
Flow Rate Indication: 8-digit positive, 7-digit negative maximum; auto decimal, lead zero blanking
Flow Totalizer: 8-digit positive, 7-digit negative maximum (re-set via keypad press, software, network command or momentary contact closure
Enclosure NEMA 4 (IP65) Construction: Powder-coated aluminum, polycarbonate, stainless steel, polyurethane, nickel-plated steel mounting brackets
Size (Electronic Enclosure Only): 152 W x 112 H x 56 mm D (6.0 x 4.4 x 2.2")
Conduit Holes: (2) ½ NPT female (1) ¾ NPT female
Temperature: -40 to 85°C (-40 to 185°F)
Configuration: Via optional keypad or PC running software (Note: not all configuration parameters are available from the keypad – i.e. flow and temperature calibration and advanced filter settings)
Engineering Units Flow Meter: Feet, gallons, cubic feet, million gallons, barrels (liquid and oil), acre-feet, lbs, meters, cubic meters, liters, million liters, kg
Inputs/Outputs USB 2.0: For connection of a PC running configuration utility
RS485: MODBUS RTU command set
4 to 20 mA: 12-bit, internal power, can span negative to positive flow/ energy rates
0 to 1000 Hz: Open-collector, 12-bit, can span negative to positive rates; square-wave or turbine meter simulation outputs
Two Alarm Outputs: Open-collector, configure as rate alarm, signal strength alarm or totalizer pulse
Transducers
Construction
Standard (FDT-41 thru 46): NEMA 6 (IP67), PVC, PEI, Nylon cord grip, PVC cable jacket
Temperature: -40 to 60°C (-40 to 140°F)
FDT-41 thru 46 with “-HT” option, FDT-47 and FDT-48: NEMA 6 (IP67), CPVC, PEI, Nylon cord grip, PVC cable jacket
Temperature: -40 to 90°C (-40 to 194°F)
FDT-47 “-HT”: NEMA 6 (IP67), PTFE, polyimide, Nickel-plated brass cord grip, PFA cable jacket
Temperature: -40 to 176°C (-40 to 350°F)
Frequency:
FDT41 thru 46: 2 MHz
FDT-47: 1 MHz
FDT-48: 500 KHz
Cables: RG59 coaxial, 75 Ω or twin axial, 78 Ω (optional armored conduit)
Cable Length: Standard 6 m (20') 300 m (990') maximum in 3 m (10') increments; submersible conduit limited to 30 m (100')
Software Utilities Utilized to configure, calibrate and troubleshoot flowmeters. Connection via USB A/B cable; software is compatible with Windows 2000, Windows XP, Windows Vista® and Windows® 7
RS485 Network All FDT-40 meters come equipped with RS485 drivers and utilize a MODBUS RTU command set (data can be returned in single-precision, double precision, integer or floating point values). Up to 126 units products can be run on a single daisy-chain network and be individually queried for flow rate, positive flow accumulator, negative flow accumulator and signal strength. Flow accumulators can be cleared at discrete addresses or globally. The RS485 network is also compatible with direct to Excel, application.

There are much less costly versions out there to be had. With some design schemes you can have numbers and alarms as well as auto pump shutdown to prevent pump damage, Omega Engineering, and GE Panametrics TransPort PT878 Ultrasonic Flow Meter Systemis another line but also high end and expensive.Plenty out there to choose from based on your need and budget.

Ron

 

Yes.

Edit: Why not use temperature?

 

the idea is to have a pre alarm to any temperature rises. i will follow the research leads. thank you. i was thinking that UV light might detect the convection currents if a suitable detector could be designed of investigated.

 

or investigated

 

If you have a serious flow monitoring application call these guys.
http://proteusind.com/
Most of our critical cooling flow systems use old school flow meters from there.

 

One nice idea is US tablet (ZP3 or any other segneto-ceramics disk-like) steered by 567-st first half and listened by the same LM567 second half. The first half is the tone generator, where the aim may be set sth between 22 and 44 kHz. Probably the voltage booster would be beneficial in the output. The second half is the PLL part where together the three options are available: to detect an accurate equal of the freq with tone in capture mode (Your case this is alarm because the flow have stopped). Other output is amplitude modulated detected signal, thus in Your case useless. Third output is frequency modulated detected signal, thus in Your case it is proportional to flow velocity. I have a feeling that this is the ideal for Yor use.

 

power to a pump would be nice but would not detect blockage. and power could be supplied via mechanical means(engine). solids would not likely unless micro organisms would count. Marine cooling system applications. is my goal. in current detection( wheels, hall effect, vanes) are all mechanical and do- able. non invasive would be an improvement.

I'd look into a venturi. Very simple, non-invasive, not terribly expensive. If you need remote telemetry instead of reading it in the field, it gets more expensive and its advantages may disappear.

 

Venturi pipe demands contact the liquid. So, formally its not what was demanded. However, practically, indeed that contact is not invasive. Just immerse and voila. But any of dozen Pitot tubes have very hard limitation = no good accuracy if speed is small. Practically, measure dP beyond the 1 mm/H2O is a real challenge, but under 0,1 all metrology becomes just flushed.
If by Venturi understand the aperture method, what may benefit with larger dP, its not applicable to opened system.
Therefore, if any immersion is permitable, the far better results (accuracy) would be obtained using a carousell type devices, like Newton cups on the rotating axle for rather violent fluxes or multiblade propeller for very mild fluxes. The data may be read by means of hercone or by means of Hall, or inductively.

The bigest flaw of any rotating system, sad to say, is wear-off what happens always too fast.

 

How accurate do you need it to be, and over what flow rate and pipe size?
Why do you need none contact?
That would rule out a magflow system. They work very well, with no moving parts, but are a bit complex. Have you looked at that option?
They are used widely.

http://aquamonix.com.au/product/m300-electromagnetic-flowmeter/
http://aquamonix.com.au/wp-content/uploads/2015/12/Emflux-2030_Rev08-08-13-Aquamonix.pdf

I have no association with this company other than some years ago, I was one of the contract designers of these products. My name probably is still on the PCBs It was a very interesting time.

 

it really is just a matter cooling water flow or no flow in lines 1"-2" diam. marine dirty water.

 

it really is just a matter cooling water flow or no flow in lines 1"-2" diam. marine dirty water.

The problem you are going to have is measuring flow with no intrusion can be done but as soon as we move from invasive to non invasive flow measurement the cost is steep. Years ago and I mean many years ago I had a 1963 Cris Craft Cavalier Express 30 footer. The boat was powered by Chevy V8 engines. Every now and then in the bay the cooling water inlets would get clogged by a plastic bag and it was obvious as that engine temp would start climbing. The fact that you only want a flow or no flow indication requires a simple flow switch with a preset level.

For a marine application you want a brass body or maybe cheaper plastic, especially for salt water applications. Switches like this are common but as soon as you get into non invasive flow measurement there is going to be a cost and with a 1" or 2" line it won't be cheap. That is as simple as it gets. You can use ultrasonic and pay or start cutting a pipe and inserting a simple flow switch. You also need to know the min acceptable flow rate for engine cooling so you can choose a correct switch for the pipe diameter.

Ron

 

thanks for your input. it is valuable to me!

 

RE:<<cutting a pipe and inserting a simple flow switch>>
then one extremely cheap but effective and longlasting thing is water level (pressure) sensor from any domestic washmachine, Bosch, Candy, Electrolux, Beco and plethora of other. It will indicate do there are pressure in the output aperture. If is, then flow is obvious. Sensor costs below the 5 USD in the spare part store.

 

RE:<<cutting a pipe and inserting a simple flow switch>>
then one extremely cheap but effective and longlasting thing is water level (pressure) sensor from any domestic washmachine, Bosch, Candy, Electrolux, Beco and plethora of other. It will indicate do there are pressure in the output aperture. If is, then flow is obvious. Sensor costs below the 5 USD in the spare part store.

That should work depending on the cooling system design. Many boats merge the seawater inlet with the exhaust so the used cooling water exits after flowing through the exhaust. Some also run cooling water through an engine oil heat exchange. You could likely place a pressure sensing switch just upstream of the inlet pump, that should work and be easy to do. Good idea and inexpensive too.

Ron