DAQ CARD INTERFACING- Analog Control of Home I/O using External Devices

Control: Connect I/O
Program Platform: FBD (Inbuilt Connect I/O)
HOME I/O Environment

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Starting Conditions: Home I/O is being controlled by Inbuilt Sensors

I/O Signals

Inputs: Brightness Sensor Analog (Bit 139)

Output:

Garden Light
Light Pool Analog (Bit 160)
Light Porche 1 Analog (Bit 158)
Light Porche 2 Analog (Bit 159)

Connect I/O Functions to be used

MUL

Step 1: Wiring Diagram With USB 4704 DAQ Card I/O Solutions:

Input Wiring:

We have connected Potentiometer 5 Kilo Ohm to the Analog Input of DAQ Card as shown. Terminal at left & right end are connected to 5 VDC & Analog Ground of DAQ Card.

The middle terminal of Potentiometer is connected to AI0 of DAQ Card. When we rotate the Potentiometer, we got 0 ~ 5VDC from Potentiometer which goes to DAQ Card and gets converted to Digital value 0.00 ~ 5.00 (Floating Value)

Output Wiring:

We have connected the Multimeter to read the Analog Output from the DAQ Card. The RED lead is connected to AO0 & Black Lead to Analog Ground of DAQ Card.

We are using Multimeter to read the feedback of Analog Sensor in Home I/O

Step 2: Connect I/O Solutions:

Step 3: Description of the Functions Used:

Source Bit: This is an ON/OFF bit used to give TRUE/FALSE Signal to Logical gates. When you press it once, it goes to TRUE & when you press is again it goes to FALSE

Bit 139: Brightness Sensor Analog: This is the standardized bit which shows the values in the range (0 ~ 8) corresponding to the Luminance outside the Smart House.

MUL (Multiplication) Function: This function multiplies the value at IN1 & X & gives the result to the OUT

Inputs can be floating OUT = IN1 * X

Bit 160: Light Pool (Analog): This is the standardized float bit used to control the luminance of Pool Light such that it’s luminance changes with the following range:

Decimal Value Luminance (in %)

0 0

2.5 25

5 50

7.5 75

10 100

Bit 158: Light Porche 1 (Analog): This is the standardized float bit used to control the luminance of Porche Light 1 such that it’s luminance changes with the following range:

Decimal Value Luminance (in %)

0 0

2.5 25

5 50

7.5 75

10 100

Bit 159: Light Porche 2 (Analog): This is the standardized float bit used to control the luminance of Porche Light 2 such that it’s luminance changes with the following range:

Decimal Value Luminance (in %)

0 0

2.5 25

5 50

7.5 75

10 100

Step 4: Explanation of Solutions:

DAQ CARD INTERFACING- Analog Control of Home I/O using External Devices

This logic has been made in Connect I/O using the functions & bits explained above.

Step 5: To Control the Analog Light Using External Potentiometer:

Objective: Following is one the objective which we need to achieve in this activity

To Control the Analog Light using External Potentiometer:

The potentiometer connected at AI0 given 0 ~ 5VDC based on its position. We have connected a Float Output with address ‘0’ which is getting the Digital value in the range 0.00 ~ 5.00.

Multiplication Factor of 2

Now, we know that the Analog Output in the Home I/0 behaves in the range 0 ~ 10 & our DAQ Card range is 0 ~ 5. So we have multiply the value of AI0 with factor ‘2’ & has given the output to Light (Type Analog) to Porche 1 (Bit 158), Porche 2 (Bit 159) & Pool (Bit 160).

Step 6: To Read the Feedback of Brightness Sensor in Multimeter:

The Brightness Sensor Bit 139 respond to the Luminance of Day light such that when Luminance is 0%, Floating Value is 0 & When Luminance is 100%, floating value is 8.

We have read its value & scale it to the range from 0 ~ 8 to 0 ~ 5 VDC by multiplying it with the factor of 0.62. We are doing the scaling because the DAQ card can give output in the range of 0 to 5 VDC only.

Calculation of Multiplication Factor: 8/5 = 0.62

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