This document describes a project to design a data acquisition system to monitor electricity supply quality at rural water pumping stations in Maharashtra. It conducted a trial run of the CIRCUITOR CVM-NRG 96 power analyzer at the Kardi water supply facility. The trial found issues like voltage dropping below acceptable levels and phases not being continuously available. The document outlines functional requirements for a standalone data acquisition system, including long-term remote data logging, power backup, flexible design, on-board display, low cost, and robust/easy operation for rural use.

1. Data acquisition system to monitor
electricity supply
CTARA Course Project
By
Rachit Aggarwal
Pushkar Limaye
Mudit Dandwate
Guide : Prof. Priya Jadhav

2. Content
1. Introduction
a. Problem statement and motivation
2. Power Analyzer Setup
a. Setup
b. Communication with the laptop
3. Trial data acquisition at Kardiwater supply facility
a. Minutes of the visit
b. Graphs of the data collected
c. Comments
4. Functional Requirements of the Data acquisition system
5. Design of data acquisition system
6. Test runs
7. Conclusions
8. Appendices
a. User manual
b. Codes
c. PCB designs
d. Vendor contact list
e. Power analyzer circutor datasheet
f. Power studio datasheet

3. 1. Introduction
Water is the basic requirement for agriculture. Agriculture was possibleonly near
a fresh water sourcebeforemodernization. Electric pumps havehowever
changed the scene completely and now even our villages are heavily dependent
on electricity.
a. ProblemStatement and Motivation:
While our villages are heavily dependent on electricity, they are also dependent
upon the quality of supply. Every machine has a tolerance limit and beyond that
its life is seriously affected. Frequentfailure of water pumps at severalpump
stations in Maharashtra draws our attention to investigate the quality of the
electricity supplied to these water pumps. Improper quality can be a surge
outside the tolerance limit or improper supply frequency. Hence, we need a data
logger that can constantly monitor the electricity supply for a long period of time
as long as 3-4 months.
2. Power Analyzer
CTARA already had an industrial power analyzer device -
CVM-NRG 96 by CIRCUITOR.
The CVM-NRG 96 measures, calculates and displays the
main electrical parameters in three phase, balanced or
unbalanced industrialsystems. Measurements aretaken
in true effective value using the three alternating voltage
inputs and three currentinputs to measure5 A
secondaries fromexternal measurement toroids.
The power analyzer outputs the parameters listed in table 1.1 which can be
either displayed on the device screen or can be given as input in Power Studio
GUI.

4. Table 1.1 Output parameters in CVM-NRG 96
a. Power analyzer set up
Setup the power analyzer as shown in the figure 2.1. Maximum voltage that
this device can safely handle is 520 V (Phaseto phase) and 300 V (Phaseto
neutral). Similarly maximum current in the external transformer is 5A. Beyond
this limit we need to place suitable current and voltage transformers.

5. Fig. 2.1 CVM-NRG 96 CIRCUITOR setup [Image source : CVM-NRG 96 datasheet]
b. Communicationbetweenand power analyzer and PC
 The Power Analyzer is connected to mains (220 V)for power supply and also connected
to the terminals for voltage measurement
 The device can measure currents upto 5A only. Hence, current transformer is required
to sense higher values. We used 100/5 CT from Hobut.
 RS485 is connected to a RS485-RS232 convertor and a RS232-USB convertor to connect
to PC
 After setting the baud rates in the device and in the Power Studio Editor, the reading
can be seen on the Power Studio Client. Real time graphs can also be observed. The
collected data can be exported to MS Excel for future use.

6. Fig. 2.2 Power studio GUI snapshot
3. Trial data acquisition at Kardi water supply facility
Place : Kardi water supplyfacility,Kardi
Date : February2, 2013
Attendee(s) : MuditDandwate,PushkarLimaye,RachitAggarwal,Technician
a. Minutes:
Load Sheddingday Friday
Ownership ShahpurJilaParishad
Water Source Batsa Dam

7. Reach 5 Villages,14km
Usage ~18 hrs/day
Equipment
Pumps Two 50 HP pumps(Onlyone ata time isused)
Capacitor To filteroutthe spikesinsupplyvoltage
Single phase
preventer
Presenttoshutdownthe pumpingincase onlyone phase ispresent
Control Units 2 separate control unitstocontrol each pump
Problems
All three phasesare notavailable all the times
One phase filterpresentbutfails sometimes –1-2 timeseveryweek
Electricitycomesandgoesabout25 timesa day
Sometimeshighvoltagesare supplieswhichdamage the coils
Meteris blownupfor 3-4 monthsnow- Theyare gettingbill usingthe formula
– (Avg.consumption+33% penalty)
Avg.monthly
consumption
~16000 units

8. Setupfor the Data logging for PowerAnalyzer
3 phase voltage
1 phase currentusing100/5 CT andClampmeterfor verificationof CT
CircuitorCVMNRG96 usingRS485-RS232-USB communication
b. Graphs for the Data loggedfor 100 mins
Fig. 3.1 3 phase voltages - kardi water supply facility – Feb 2,2013
Fig. 3.2 Current - kardi water supply facility – Feb 2,2013

9. Fig. 3.3 Frequency - kardi water supply facility – Feb 2,2013
Fig. 3.4 Frequency distortion - kardi water supply facility – Feb 2,2013
c. Comments
Accordingto IEEE standardsthe voltage shouldnotdropbelow the 5% andexceed3% of the standard
highvoltage supply.For415V, itshouldbe between394.25V and 427.45V, whichis contraryto the data,
where ittouches385V at times.
Otherparametersare in the range.

10. 4. Functional Requirements of standalone dataacquisitionsystem
 Long time data logging: small data is of no use for such investigations. Long time
continuous data would give us actual insight of the problem
 Remote data monitoring : It is very inconvenient to go to one supply station and
collect the data there. Thus, remote monitoring of the data is highly desired.
 Power back up : Villages seldomhave continuous power supply. Sudden electricity
failure can lead to serious data loss or corruption of the data collected. Hence,
power backup is required to shutdown the files.
 Reprogrammable and flexible architecture to support multiple modules : We
would also like the device to be reprogrammable atleast while the device is in
testing. We would also like the device to have a flexible architecture to support
multiple modules.
 On board display: We would like to provide user a interface to setup the device and
monitor the device without any laptop or computer. It would also help the end user
in setting up the device to log data using some other power analyzer module.
 Low cost: As the device needs to be kept in rural areas. It is important that the
device cost is kept as a low as possible. Also, low cost would mean more number od
supply stations being monitored in small budget.
 Robust and easy to handle: As the device would be kept in a rural place and
technician can seldom reach to fix the device, we would like the device to be robust.
Also, to enable anyone with bare minimum knowledge to handle the device we want
to keep the usage as simple as possible.