Metering community that includes the engineers from electrical utility, manufacturer & test laboratories are working harder and harder to reduce the revenue losses due to tampering in the energy meter by the consumer. Several years of study and experience reveals that there are numerous possibilities to manipulate with meters supply wiring. Tamper protection is highly important issue for utility, meter manufactures & test labs. Various governmental schemes such as APDRP/R-APDRP also emphasizing to have tamper proof meters. It is extremely challenging to remember & simulate all these various combination while testing the tamper proof functionality of single phase energy meter.
This application note explains how the tamper simulator (1phase) has made easier and systematic to test the tamper testing without making any change in the external connection in the meter.
Test engineer encounter the following difficulties while testing the tamper recording or tamper proof feature in the single phase meters.
Several years of research & discussion with the metering experts in the field of tamper detection, analysis & diagnoses, meter testing & manufacturing; SNG has developed a tamper simulator based on microprocessor control circuits.
The simulator is capable of creating 38 different types of tamper conditions by just selecting the predefined tamper condition (see Annex 1 for all tamper test conditions) using the feather touch key pad. The selected tamper condition will be displayed on the LCD display. Operator need not to change any physical connection or to do re-wiring to create a tamper condition. Meter connection terminal is provided for easy and quick connection through spring loaded quick connectors.
The digital panel meters are provided to indicate the voltage, current & current during partial load.
A programmable timer is provided to programme the ON time, OFF time and number of cycle for which test has to be carried out as per tamper condition
The tamper simulator save the great amount of time and provides chances to diagnose the meter functionality thoroughly without fatigue to tester.
The tamper simulator has following features:-
The below mentioned tamper conditions are the primary group of various simulated tampers condition (38):
The tamper simulator save the great amount of time and provides chances to diagnose the meter functionality thoroughly without fatigue to tester. The tamper simulator is designed to provide following benefits to test engineers such as
|Input Supply Voltage||1ph 240 V, 50Hz (protected by fuse & MCB)|
|Output supply voltage||Same as input|
|Output current||Output Current Full load – 5 Amp @240V
Partial load – 2.5 Amp @240 V
|Output loading||Resistive load for full and partial loading|
|Display /Indications||v LCD display to indicate selected different tampers
v Mains ON indication lamp
v Voltmeter for output voltage
v Ammeter for full load current
v Ammeter for partial load current
|Controls||v Mains ON/OFF switch
v User friendly feather touch keypads to select different tamper conditions
v Potentiometer to vary the firing angle in AC chopped signal
|Connections||Spring loaded quick acting device for MUT
Separate terminal for standard meter
|Measurement of errors
|System to measure error under different tamper conditions
v Display and measurement unit
v Scanning head to pick the pulse
|1S = Phase voltage (wire) at Supply side of meter||2S = Neutral voltage (wire) at supply side of meter|
|1L = Phase voltage (wire) at Load side of meter||2L = Neutral voltage (wire) at load side of meter|
The conditions explained in this application note are with the objective to assist the test engineers to fight against the energy tampering where ever it is taking place. We request the readers of this application note to use the document carefully and ensure that it does not land up in the wrong hands.
In any case, SNG is not responsible and does not take any liability, in any form on spreading the content of the application with wrong intentions or for wrong purposes and subsequent losses or damage occurred due to it.
RPP Engineering & Consulting GmbH
Winzer Str 20, 53639 Königswinter Germany
Tel no +49 2223 906647