10/16/2016

1

Fall 2013

Honore Hodary

Motivation Overheating is one of the most common cause of failure in DC motors. It can lead to bearings failure (motor jam), winding‐isolation (short‐circuit), and degradation of the magnets.

The amount of current drawn and the temperature generated by DC motor are crucial in understanding the performance and reliability of motors.

Provide a low cost and effective tool for measuring the amount of current drawn and heat generated by DC motors.

10/16/2016

2

Goals

Provide a cost effective mechanism for acquiring temperature and current data.

Allow the operator to determine when to perform preventive maintenance.

Record the temperature and current data to a host computer.

Display current and temperature data on LCD

Design a compact, portable, and user friendly system.

Functional Requirements

Measure the heat (temperature) generated by the motor.

Measure the amount of current drawn by the motor.

Record temperature and current data to a host computer for later analysis.

Display current and temperature data on LCD display.

10/16/2016

3

Specification Measured temperature shall be in the range of 0 to 300 degrees Fahrenheit.

Measured current shall be in the range of 1 to 15 A.

The temperature accuracy shall be within +‐2 degrees Fahrenheit.

The current accuracy shall be within +‐100 mA

Both temperature and current should be transmitted to a host computer every 60 seconds.

The operating temperature shall be between 0 and 100 degrees Fahrenheit.

The system shall not exceed 4 lbs.

System Block Diagram

10/16/2016

4

Subsystems Sensors module

Power supply module

Microcontroller module

Data display module

Data storage module

Signal conditioning module

Sensors Selection Criteria Transfer function must be linear

Response time must less than 100 ms

Must have great accuracy

Noise level must be less than 100 mV

Dynamic range must be between 0 A and 15 A

Must be easy to use

10/16/2016

5

TLS 15‐NP Current Sensor Type: Hall Effect

Maximum measure current: 15 A

Supply voltage: 5V

Supply current: 1.6 mA

Output type: voltage

Response time: <100 ns

Sensitivity: 41.6 mV/A

TLS 15‐NP

10/16/2016

6

CSLA2CD Current Sensor

Type: Hall Effect

Max Current: 72 A

Supply Current: 10 uA

Supply Voltage: 8V – 13.2V

Output type: Voltage

Response Time:3us

Sensitivity: 32.7 mV/A

CSLA2CD Sensor

10/16/2016

7

Sensors (Continued) Temperature Sensor (LM34)

Internally calibrated

Linear Output: 10mV/Degree Fahrenheit

Supply Voltage: 5V to 30V

Supply Current:75 uA

Response Time:750 mS

Measurement Range: ‐50 to 300 Degrees Fahrenheit

Accuracy: +‐2 Degrees

LM34 Sensor

10/16/2016

8

DS1820 Dynamic range: ‐67 to 257

Accuracy: 0.5 degrees Fahrenheit

Resolution: 10 bits

Cost: $6.00

DS1820

10/16/2016

9

Op Amp Selection

LM 741

Dual power supply

Well balanced

Easy to use

CMP601

Single supply

Requires virtual ground

Hard to design

Single Supply Op Amp

10/16/2016

10

Signal Conditioning Module

Temperature Sensor Signal Conditioning Circuit

VCC

5V

U1

MCP601-I/P

3

2

4

7

6

RG

47kΩ

RF

329kΩ

C1

0.01µF

C20.01µFR2

820Ω

R1615Ω

VDD5 V

VinVout

10/16/2016

11

Current Sensor Signal Conditioning Circuit

U2

MCP601-I/P

3

2

4

7

6

R3

47kΩ

R4

329kΩ

C2

0.01µF

C30.01µF

R5820Ω

R6615Ω

VDD5 V

U4

MCP601-I/P

3

2

4

7

6

VCC

5V

VCC

5V

R11

137kΩ

R12

137kΩ

C6820pF

C8

1.64nF C9

0.01µF

U5

MCP601-I/P

3

2

4

7

6

C10

0.01µF

VCC

5V

Vin

Vout

Power SupplyWall adapter

Input: 110V – 125V

Output: 12V

Current: 1A

Regulator

Type: LM7805

Voltage: 5V

Current: 1A

10/16/2016

12

Power Supply Schematic

U1LM7805CTLINE VREG

COMMON

VOLTAGE

C1.01µF

C2.01µF

D11N4007G

OutputInput

USB Communication Module FT232R Controller

Provides communication channel between the MCU and the host computer.

Converts USB port to Virtual COM port in the host computer.

Manages enumeration and other USB bus communication requirements in hardware.

No USB specific firmware required.

Supports Bus‐powered and Self‐powered.

USB 2.0 full‐speed compatible.

10/16/2016

13

USB Controller (continued) Operating temperature: ‐40 to 85 degrees C.

Supply voltage: 1.8V to 5.25V.

Supply current: 15mA

Data transfer: 300 baud to 3 Mbaud.

USB Controller Schematic

10/16/2016

14

Microcontroller PIC18F4550

Analog‐to‐digital conversion (ADC)

Process temperature and current data.

Transfers temperature and current data to the host computer.

Display temperature and current data on LCD display.

Microcontroller Communication With USB Controller

Communication With DAC

Communication with LCD display

10/16/2016

15

Microcontroller (continued) Supply voltage: 2V to 5.5V

Supply current: 5.8 uA

Sink/source current: 25mA

Clock: Internal and external oscillator.

Timers: 4

ADC resolution: 10‐bit

Analog channels: 13

Interrupt sources: 20

Microcontroller Schematic

10/16/2016

16

System Integration

U3

UM232R

123456789101112 13

1415161718192021222324

U2

MCP601-I/P

3

2

4

7

6

R3

47kΩ

R4

329kΩ

C2

0.01µF

C30.01µF

R5820Ω

R6615Ω

U4

MCP601-I/P

3

2

4

7

6

R11

137kΩ

R12

137kΩ

C6820pF

C8

1.64nF C9

0.01µFU5

MCP601-I/P

3

2

4

7

6

C10

0.01µF

J3

PJ-102A

U7

GND

VCCCV

RSRW

E

D0D1D2D3D4D5D6D7

U8LM7805CTLINE VREG

COMMON

VOLTAGE

D1 1N4007G

C50.33µF

C70.1µF

D2

1N4007G

S1Key = Space

0

VCC

5V

VCC

VCC

VCC

VCC

U1LTSR 15_NP

1234 5 6

789

10

J1

HDR1X2

1

2

Isense_In

Isense_Out

VCC0

OUT

0 0

C1

0.01µF

U6

MCP601-I/P

3

2

4

7

6

R8

137kΩ

R9

137kΩ

C4820pF

C11

1.64nF C12

0.01µFU9

MCP601-I/P

3

2

4

7

6

R1

6kΩ R210kΩ

RG

6kΩ

RF

10kΩ

C13

0.01µFU10

MCP601-I/P

3

2

4

7

6

J2

HDR1X3

1

2

3

VCC

0

0

0VCC

0

0

VCC

0

U11

PIC18F4550

1234567891011121314151617181920 21

22232425262728293031323334353637383940

R7

10kΩ

C1422pF

C1522pF

VCC

VCC0

X1HC-49/U_11MHz

0

VCC0

AN0

AN0

AN1

AN1

VCC

0

RB3

RB3RB2

RB2

RB1

RB1

RB0

RB0

0

RB5

RB5

0RB4

RB4

0

VCC

0

00

VCC

0

0

0

00

0

0

0

0

Software Architecture

10/16/2016

17

Software: Microcontroller

Programming language: C

Program Initialization Configure ports

Configure ADC

Configure USART

ADC Conversion Reads data from analog channels

Format data

Data transfer/display Transfer data to the host computer

Display data on LCD display

Algorithm: Microcontroller

10/16/2016

18

Statechart

Testing and Validation

10/16/2016

19

Testing and Validation

Cost and Resource Management

Part Name Quantity Price Per Unit Total Cost

Actual Amount of Money Spent

MCP601 Op Amp 6 $0.60 $3.60 $3.60

TLS 15-NP Current Sensor

1 $17.00 $17.00 $17.00

LM34DZ Temperature sensor

1 $6.60 $6.66 $6.60

Resistors 17 $12.00(per kit) $12.00 $0.00 (Had it )

Capacitors 15 $9.00 (per kit) $9.00 $0.00 (Had it)

UM232R USB-to-UART Converter

1 $11.00 $11.00 $21.00

PIC18F4550 1 $6.90 $6.90 $0.00(Had it )

Terminal Blocks 2 $1.00 $2.00 $0.00 (removedfrom power supply)

Barrel power Jack 1 $3.00 $3.00 $0.00 (removed from an old router)

Diode 2 $6.00 (per kit) $12.00 $0.00 (purchased two years ago)

Oscillator 1 $4.00 $4.00 $0.00 (Had the part in my tool box)

Total $97.16 $48.20

10/16/2016

20

Risks

The microcontroller not sending data to PC

The temperature sensor not being attached to the motor

Lesson Learned

Project management

Planning is key to a successful project

Always buy extra components in case one get damaged

Gained valuable experience in analog signal conditioning

Gained experience programming PIC microcontroller

10/16/2016

21

Conclusion

All features of the USB Based Data Acquisition System were successfully implemented

The cost of designing the UBS Based Data Acquisition System was well bellow $100

Did not have enough time to focus on the project as given my work related responsibilities

Overall, this was a very rewarding experience

Thank you.

Questions?