# Wind Velocity Anemometer Help

Wind Velocity Anemometer - December 2022
We need your help. We have a wind velocity anemometer and need to provide a dry contact output as elected from an operator at different wind speeds such as 25, 30, 35, 40 etc. miles per hour. The anemometer can provide an output of 25 mph of some low voltage, frequency not known . See chart below. Your suggestion and how can we set the contact to be activated by different wind velocity setting as determined by the operator. The range of selection should be from zero wind speeds to 100 mph wind speeds. Thanks, Bruce Balderson, BDS Systems Inc. We mfg. lighted windsocks.
Wind Velocity Anemometer Outputs 12/15/2022 21:21
Line MPH DC Volts Frequency Hz
1 0 0.00 0
2 5 0.36 6.66
3 10 0.78 13.33
4 15 20
5 20 1.65 26.66
6 25 33.325
7 30 2.38 40
8 35 46.655
9 40 3.12 53.32
10 45 60
11 50 3.83 66.65
12 55 73.315
13 60 4.60 80
14 65 86.645
15 70 5.36 93.31
16 75 100
17 80 6.11 106.64
18 85 113.305
19 90 0.90 120
20 95 126.635
21 100 7.65 133.33

Welcome to the Tech Forum!

Your data list seems to be a bit inconsistent (sometimes 4 values, sometimes only 3), but it would appear that your anemometer consistently outputs 1.33333 pulses per mph. I’m not clear what is meant by your voltage output, as the data sort of implies and analog output voltage, and not a linear one at that.

In any case, your linear frequency output relative to the wind velocity is what you would want to use. My first question is, what is the nature of that anemometer output? Is it a square wave of some fixed voltage (such as 12V, 0V), is it a contact closure type output, or something else?

Second, what sort of device are you looking for to sense this anemometer output, calculate the velocity, and control the dry contact output? It can be accomplished with a multitude of microcontroller types, an Arduino style board, or a more integrated device like a DIN rail-mounted process controller such as the IFMR0036.

The IFMR0036 is by far the most expensive, but it is fairly trivial to configure for your application. The others involve programming and more electronic component experience, possibly including creating a circuit board. If you are doing a small number of these, then that’s probably the best way to go, as will take the least amount of time and require the least amount of background development.

It appears to me that the table is missing data in what would appear to be every other row; I’m interpreting things as being a DC signal proportional to wind velocity at roughly 77mV/MPH.

If that’s the case, one could use a low-power comparator, voltage reference, some resistor dividers, and a pair of back-to-back FETs to build an analog solution. Something made from multi-source/generic parts that lasts years on a set of batteries should be quite doable.

Thanks. Can you give me more details with pricing. Bruce

Thanks for the reply. This the info I got from Texas Electronics. Gan you give me more info and pricing of what you suggest? We would like to ADD the feature to the top of our lighted windsock system. But that not in the cards right now. Bruce Balderson BDS Systems Inc.

Hi Bruce,

Which of those anemometers are you considering? That may affect which options may be worth considering, or it may require making some sort of adapter to be able to interface with the control device. For the solutions I discussed, a series of pulsed square waves are most convenient to deal with, whereas for Rick’s solution, one would need the analog voltage output.

Regarding pricing, the IFMR0036 can be found here, where you can see pricing and related information. With this controller, you would need to provide power, either 85Vac-250Vac or 9Vdc-32Vdc, depending on the model. If being used outdoors, you would have to enclose in a weather-proof box, and you would typically mount it on a DIN rail, so those items plus miscellaneous hardware would add to overall cost.

With the Arduino-type options, pricing ranges from about \$8 to over \$40 for various options, but these will require additional components to complete a design. If you are not familiar with using an Arduino or microcontrollers already, you would either need to educate yourself or hire someone to help with such a design.

Regarding Rick’s suggestion, that’s a perfectly viable option if his assumptions about the nature of your output voltage vs. wind speed are correct. That solution also requires some familiarity with basic electronic components, but the actual components can be acquired for a few dollars. One would have to design a printed circuit board to complete that design, so again, if you’re not already experienced in such things, you might want to hire someone to do the design work if you choose to go that way.

David Engineering Digi-Key. We have reviewed the below info. Attached is some additional info. The last time I emailed to you it did not go through. See below and Merry Christmas and happy holidays. Bruce Balderson

Wind Velocity Anemometer Outputs - TV-114/114A

12/22/2022

Line

RPM

MPH

AC Volt

DC Volts

Frequency Hz

Notes:

1

0

0

0.00

0.00

0.000

AC Generator produce an AC sine wave

2

50

5

0.22

0.35

6.660

where the amplitude and frequency

3

100

10

0.45

0.78

13.330

are proportional to wind speed.

4

15

20.000

5

200

20

0.96

1.65

26.660

TV-114 (AC Unit)

6

25

33.325

1.0 mph = 1.33Hz, 100 mph = 133.33 Hz

7

300

30

1.43

2.38

40.000

8

35

46.655

TV-114-A, wind sensor, 4-20mA

9

400

40

1.92

3.12

53.320

4mA = 0 mph, 20mA = 100 mph

10

45

60.000

11

500

50

2.38

3.83

66.650

12

55

73.315

We need electronics an operator can use to provide

13

600

60

2.96

4.60

80.000

a switch closed output signal for any setting an operator

14

65

86.645

selects from the anemometer shown at left.

15

700

70

3.32

5.36

93.310

The unit should include a time delay an operator may

16

75

100.000

set to eliminate short burst of wind speeds. Wind fluctuations.

17

800

80

3.79

6.11

106.640

Adjustable from 0 to 380 seconds or another.

18

85

113.305

19

900

90

4.25

6.90

120.000

20

95

126.635

21

100

100

4.70

7.65

133.330