
List of required components
NR: | Type of component: | Quantity |
1 | Baseplate | 1 |
2 | Washers 6 mm | 40 |
3 | M6 Threaded rod 135 mm | 10 |
4 | M6 Hex nut | 42 |
5 | Compression lid | 1 |
6 | Compression lid knob | 2 |
7 | M6 Hex bolt 35 mm | 2 |
8 | Sealing ring | 1 |
9 | Fan outlet | 1 |
10 | M4 bolt 50 mm | 2 |
11 | Venturi outlet | 1 |
12 | Tube OD=14 mm ID=32 mm L=100 mm | 1 |
13 | Brackets 14 mm tube | 4 |
14 | P1 sensor connector 14 mm tube | 1 |
15 | Venturi inlet | 1 |
16 | Tube OD=40 mm ID=32 mm L=100 mm | 1 |
17 | Brackets 40 mm tube | 2 |
18 | P1 sensor connector 40 mm tube | 1 |
19 | Dummy head | 1 |
Electrical components | ||
20 | Arduino Uno | 1 |
21 | Arduino prototype shield | 1 |
22 | Wires | Plenty |
23 | USB A to B | 1 |
24 | Analog Differential pressure sensor Range: 500 Pa | 2 |
25 | Relay | 1 |
26 | Power supply 24V | 1 |
27 | Fan, min static pressure = 490 Pa | 1 |
Specification of the electrical hardware
Fan
General comment:
Able to build up a static pressure of >400Pa, in combination with a flow of at least 200L/min
Specification sheet:
https://products.sanyodenki.com/en/sanace/dc/blower/9BMB24P2H01/
Analog pressure sensors
General comment:
500 Pa sensor, depending on the type of fan used in the setup.
Specification sheet:
https://www.sensirion.com/en/download-center/differential-pressure/sdp800-proven-andimproved/
Before you start
Before you start you should print the following parts:
- Fan outlet
- Compression lid knob
- Venturi outlet
- 14 mm Tube brackets
- P2 pressure sensor connector for 14 mm tube
- Venturi inlet
- 40 mm Tube brackets
- P1 pressure sensor connector for 40 mm tube
Building steps
Part 1: Mechanical setup
Step 1
Create a baseplate with dimensions 550 x 200 mm. The shape and holes can be made by laser-cutting (see the DXF-file) or by manual drilling.
Step 2
Take 4 rods of at least 135mm and attach them with nuts and washers onto the baseplate, see figure 1.

Step 3
Glue the fan on the fan outlet in the orientation shown in figure 2.

Step 4
Take the fan outlet and place it onto the 4 threaded rods of the previous step, and fasten it down with 4 nuts and washers, figure 3.

Step 5
Take the sealing, lay it on the top of the fan outlet, figure 4. Insert 2 M6 hex nuts in the fan outlet, figure 5. Take the compression lid knobs, insert them with 35mm M6 hex bolts and bolt down the compression lid, figure 6.



Step 6
Take again 4 rods of at least 135 mm and assemble it with washers and M6 hex nuts onto the baseplate, figure 7.

Step 7
Insert the brackets for the 14mm tube on the rods installed in step 6, figure 8.

Step 8
Drill in the 14mm tube a hole of 1 mm, at least at 1 Diameter length from the Venturi inlet, and glue the pressure sensor connector on the tube, such that it is concentric with the drilled hole, figure 9,10.


Take the Venturi outlet and insert the 14 mm tube, when assembled bolt it on the fan with two M4 50mm bolts and fasten it with M4 nuts, figure 10.
Then, clamp the 14mm tube down with the top brackets washers and nuts, figure 11.

Step 9
Assemble again 2 threaded rods on the baseplate with washers and nuts and install the bracket for the 40 mm tube, figure 12.

Step 10
Attach the Venturi inlet on the 14 mm tube, figure 13.

Step 11
Drill in the 40mm tube a hole of 1 mm, at least at 1 Diameter length from the Venturi inlet, and glue the pressure sensor connector on the tube, such that it is concentric with the drilled hole, figure 14,15.


Step 12
Insert the tubes coming from the pressure sensors with glue in the holes of the fan outlet, pressure sensor connector on the 14mm tube and on the 40 mm connector, figure 16.

Step 13
Last but not least, attach the dummy head to the 40 mm tube, figure 17.

Part 2: The electrical circuit
In figure 18, the wiring schematic is shown to instruct how the hardware should be connected to the Arduino.

An Arduino prototype shield makes it more convenient to build the circuit, as shown in figure 19.

Upload the pressure_drop_arduino_main.ino to the Arduino uno. Proceed with the readme file to see how to conduct measurements.