Download DC power monitor - Texas State University

Group: CCM
Project 1.2
EMERSON
Emerson is a diversified global manufacturing company.
 Provides innovative solutions to customers in the following
areas:
Process Management
Industrial Automation
 Network Power
 Climate Technologies
 Commercial & Residential Solutions ​
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Goal
Emerson 24Vdc Monitor.
 This device will monitor for 24Vdc. Upon a decrease or increase of
5% of 24Vdc the device will record.
 Measurements include:
 Amplitude of the voltage
 Duration of the change in voltage
 Time at which the change occurred, and provide a waveform of the
collected data.
 Remote Access
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Why our Solution?
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Other Devices are costly can be as great as $4000

These systems can be bulky
The anticipated sample rate is much lower
than most commercial products
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Remote Accessible
Proposal
The system we consist of:
 Protective circuit
 Comparator
 A Step down prior to the ADC
 MAX 1257 ADC
 Aliasing Filter
 Raspberry Pi 2
The Protection Circuit

The Protection Circuit will
consist of:
 A fuse
 Zener diode

Other possibilities
 A small Breaker
Raspberry PI 2
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900MHz quad-core ARM Cortex-A7 CPU
1GB RAM
Ethernet port for remote access
Micro SD card slot for extra storage
SPI interface for fast data transfer between ADC and the PI
Low power consumption
Easily Remote accessible
MAX1257 Analog to Digital Converter
16 channel 12-bit ADC
 25MHz SPI interface
 225,000sps( samples per second ) ≈ 1 sample per 4µs
 Low power consumption 2.5mA at 225ksps
 -.3V to 6V analog range.

Timeline
Data Processing
The Raspberry Pi will continuously take values from the
ADC
 When the comparator sends an interrupt, the PI will
record the last 100 values into memory along with a
timestamp
 The comparator will be at logic level 0 when the voltage
is <25V
 The comparator will be at logic level 1 when the voltage
is >25V
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Remote Access

Windows Remote Access: Using an SSH Client such as
Putty

Static IP Address
By simply typing the IP address
of the PI into the host name
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Testing the Power Monitor
The system will be tested using a Pulse
Transformer and a Signal Generator to
create and control spikes in Voltage
Budget
Raspberry Pi 2 - $35
 Maxim ADC 1257 – $25.43
 Pulse Transformer - $ 4.79
 Bread Board - $4.50
 Misc. (resistors, fuses, wire) - $15
 Total:
$84.72
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Question ?????
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At this point we will entertain questions