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JPS digital meters still under a cloud of suspicion
Wignall's World
Mark Wignall
Sunday, October 30, 2011
IN last Sunday's column, I carried a section titled 'Mr Hedley Jones questions JPS meters' in which it was pointed out that it was likely that the new digital meters could be reading up to one-and-a-half times the power that the old analog meters registered.
This, to me, explained why my own digital meter, since it had been installed, has carried my monthly bills to, on average, $24,000 when during the times the old analog one was connected my monthly bills were in the region of $15,000.
Many people have complained to me and various media outlets about these huge increases which have only one thing in common. The installation of the digital meters.
JONES… says the digital meter is one of the most horrendous corporate scams of the 21st century
1/2 
A friend of mine from school days, a Jamaican electrical engineer living and working in Canada since he left JPS in the 1980s, e-mailed me a response to the column. Again, the language is technical but the details have to be stated because it appears that whoever has given the JPS digital meters a clean bill of health is probably relying on the perceived ignorance of Jamaicans to carry the day and to convince us that so many of JPS's consumers are stupid.
Said he: 'I just got a chance to read your piece. Jones is dead right. The old type meters responded to and read the RMS or effective values of the power supplied. Below is the proof that substantiates the claim that for the same connected equipment, electricity bills have gone up since the introduction of the digital meters.
'This is the theory. The voltage that is supplied to the consumer is a standard sine wave. A sine wave has a periodic positive and negative maximum and minimum value over one cycle. In Jamaica, this variation happens 50 times per second (frequency). A standard was adopted to use the RMS value of the maximum value, Vpk for the effective value of voltage for consumer's use. There is a definite mathematical relationship between these values.
'Proof: The mathematical relationship between a pure sine wave Vpk and Vrms is :Vrms =root 2/2 * Vpk; The resulting current that flows in the load (l) is, Irms, and has the same relationship, Irms =root/2 * Ipk. The power ( Po), supplied and billed to the consumer using the old meters is the product of the effective values of voltages and current. Thus, Po = Vrms * Irms. Substituting for Vrms and Irms in terms of Vpk and Ipk, Po = root 2/2 * Vpk * root 2/2 * Ipk; this simplifies to (Vpk * Ipk) / 2.
'The units of measurement are kilowatt hours for consumption purposes over time. Now, if the new digital meters are designed to read peak values and not effective values, then the power supplied to the same household will be read as Pd = Vpk * Ipk.
'Comparing Pd with Po: ie Pd/Po becomes Vpk *Ipk (Vpk * Ipk/2) which simplifies to 2 .
'Conclusion: The significance is that theoretically, if the meters are true peak-reading, then they would register twice as much power for the same load assuming a pure sine wave is applied to it. If they are not designed to read effective values, that is true RMS values, or true peak, then the actual readings may fall somewhere between true RMS reading as would the old meter and twice as shown above on a true peak reading digital meter.
'The OUR needs to have a detailed look at the specifications of these meters to determine what values they are designed to read.'
I sent the response to Mr Hedley Jones, teacher, musician, inventor, engineer and Musgrave Gold medallist for his comments.
He said: 'Thanks, Mark for your friend's professional input. I was commissioned by the Board of Kingston Technical High School in 1959 to set up electrical and radio classes at that school. I did and taught those subjects at that location for five years before leaving the city in 1965.
'As far as I am aware, the Jamaican electrical engineers seem to be afraid of ruffling feathers. They should know the Math, even if they did not do the practical. If I can obtain a schematic diagram of the digital meter, I would be able to determine its working parameters.
'Until then I still maintain that that instrument registers all, repeat all line losses, including Hysteresis, back emf, eddy current, low power factor, and frictional losses. They claim it is noted for its efficiency. Indeed it is. It makes you pay for all natural line losses which, on any system, is inevitable wastage.
'Until I am able to prove otherwise, I maintain that the digital meter is one of the most horrendous corporate scams of the 21st century. You are at liberty to publish my opinion if you so desire.'
If two highly competent Jamaican professionals can arrive at almost exactly the same damaging conclusion on the new digital meters, that they may be registering between one-and-a-half to twice the readings of the old analog ones, why should I believe anything that JPS or any of its surrogates choose to tell this nation?
Something is radically wrong. The meter at my home is an Itron watt hour meter, 50 hz - CL 200 240 v 3w, type CIS 3OTA 1.0KH.
The recent report in which the JPS digital meters were given a clean bill of health needs to be opened up to the public so that we can make a judgement. Frankly, based on the Jamaican public's justifiably poor view of the OUR, if the OUR tells me to turn left, I know for certain that I must head right.
Read more: http://www.jamaicaobserver.com/colum...#ixzz1cJWLap00
Wignall's World
Mark Wignall
Sunday, October 30, 2011 IN last Sunday's column, I carried a section titled 'Mr Hedley Jones questions JPS meters' in which it was pointed out that it was likely that the new digital meters could be reading up to one-and-a-half times the power that the old analog meters registered.
This, to me, explained why my own digital meter, since it had been installed, has carried my monthly bills to, on average, $24,000 when during the times the old analog one was connected my monthly bills were in the region of $15,000.
Many people have complained to me and various media outlets about these huge increases which have only one thing in common. The installation of the digital meters.
JONES… says the digital meter is one of the most horrendous corporate scams of the 21st century 1/2 A friend of mine from school days, a Jamaican electrical engineer living and working in Canada since he left JPS in the 1980s, e-mailed me a response to the column. Again, the language is technical but the details have to be stated because it appears that whoever has given the JPS digital meters a clean bill of health is probably relying on the perceived ignorance of Jamaicans to carry the day and to convince us that so many of JPS's consumers are stupid.
Said he: 'I just got a chance to read your piece. Jones is dead right. The old type meters responded to and read the RMS or effective values of the power supplied. Below is the proof that substantiates the claim that for the same connected equipment, electricity bills have gone up since the introduction of the digital meters.
'This is the theory. The voltage that is supplied to the consumer is a standard sine wave. A sine wave has a periodic positive and negative maximum and minimum value over one cycle. In Jamaica, this variation happens 50 times per second (frequency). A standard was adopted to use the RMS value of the maximum value, Vpk for the effective value of voltage for consumer's use. There is a definite mathematical relationship between these values.
'Proof: The mathematical relationship between a pure sine wave Vpk and Vrms is :Vrms =root 2/2 * Vpk; The resulting current that flows in the load (l) is, Irms, and has the same relationship, Irms =root/2 * Ipk. The power ( Po), supplied and billed to the consumer using the old meters is the product of the effective values of voltages and current. Thus, Po = Vrms * Irms. Substituting for Vrms and Irms in terms of Vpk and Ipk, Po = root 2/2 * Vpk * root 2/2 * Ipk; this simplifies to (Vpk * Ipk) / 2.
'The units of measurement are kilowatt hours for consumption purposes over time. Now, if the new digital meters are designed to read peak values and not effective values, then the power supplied to the same household will be read as Pd = Vpk * Ipk.
'Comparing Pd with Po: ie Pd/Po becomes Vpk *Ipk (Vpk * Ipk/2) which simplifies to 2 .
'Conclusion: The significance is that theoretically, if the meters are true peak-reading, then they would register twice as much power for the same load assuming a pure sine wave is applied to it. If they are not designed to read effective values, that is true RMS values, or true peak, then the actual readings may fall somewhere between true RMS reading as would the old meter and twice as shown above on a true peak reading digital meter.
'The OUR needs to have a detailed look at the specifications of these meters to determine what values they are designed to read.'
I sent the response to Mr Hedley Jones, teacher, musician, inventor, engineer and Musgrave Gold medallist for his comments.
He said: 'Thanks, Mark for your friend's professional input. I was commissioned by the Board of Kingston Technical High School in 1959 to set up electrical and radio classes at that school. I did and taught those subjects at that location for five years before leaving the city in 1965.
'As far as I am aware, the Jamaican electrical engineers seem to be afraid of ruffling feathers. They should know the Math, even if they did not do the practical. If I can obtain a schematic diagram of the digital meter, I would be able to determine its working parameters.
'Until then I still maintain that that instrument registers all, repeat all line losses, including Hysteresis, back emf, eddy current, low power factor, and frictional losses. They claim it is noted for its efficiency. Indeed it is. It makes you pay for all natural line losses which, on any system, is inevitable wastage.
'Until I am able to prove otherwise, I maintain that the digital meter is one of the most horrendous corporate scams of the 21st century. You are at liberty to publish my opinion if you so desire.'
If two highly competent Jamaican professionals can arrive at almost exactly the same damaging conclusion on the new digital meters, that they may be registering between one-and-a-half to twice the readings of the old analog ones, why should I believe anything that JPS or any of its surrogates choose to tell this nation?
Something is radically wrong. The meter at my home is an Itron watt hour meter, 50 hz - CL 200 240 v 3w, type CIS 3OTA 1.0KH.
The recent report in which the JPS digital meters were given a clean bill of health needs to be opened up to the public so that we can make a judgement. Frankly, based on the Jamaican public's justifiably poor view of the OUR, if the OUR tells me to turn left, I know for certain that I must head right.
Read more: http://www.jamaicaobserver.com/colum...#ixzz1cJWLap00
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