Date Author Phone direct / . April 2016 Horst Adams

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1 Guideline P.O. Box 7550 CH-6302 Zug / Switzerland Physical Address: Dammstrasse 16 CH-6300 Zug / Switzerland Phone Fax Date Author Phone direct / April 2016 Horst Adams adams@mte.ch How to locate customer needs in the field of portables for electricity meter testing Customer requirements in the field of meter testing are sometimes a little bit confusing. The representative is challenged to offer suitable equipment or to give sufficient information to the principal in order to work out a quotation. This paper can be used as a guideline in the discussion with the customer. Depending on the local situation some questions do not make any sense or others should be added. 1. General questions 1.1 Where does the customer want to test meters? Laboratory conditions On-site Rough factory environment (without air conditioning etc.) Usage in laboratory and on-site Laboratory conditions mean clean environment with air conditioning and controlled humidity. Here all test equipment can be offered. In all other cases you have to know, which environmental influences exist and if the offered unit is suitable for this purpose. 1.2 How many meters should be tested simultaneously? 1 Meter 2 Meters 3 Meters More than 3 meters In case of 1 meter testing, all portable reference standards are possible. In case of testing 2 meters at the same time PWS 3.3 and PWS2.3 genx are available. For 3 meters PRS 600.3, CALPORT 300 or K2006 are possible. For 4 meters and more it should be a stationary system (see guidelines stationaries) 1.3 Transportation capability of the unit Portable Moveable Stationary Portable (see next chapter) Moveable (tailor made; contact your principal) Stationary (see guideline stationary test equipment)

2 Page 2 / 5 2. Questions regarding Portable test equipment In the range of portables we principally have following alternatives (tables see ppt file). To find out suitable solutions for the customer, some information are useful: 2.1 What kind of meters should be tested? Electro mechanical meters Whole current meter Maximum demand meter Max. number of Maximum Demand registers:.. Further technical data Nominal frequency - 50 Hz - 60 Hz /3 Hz Minimum nominal current: Maximum current: Max. voltage Phase-Neutral: Phase-Phase: Highest accuracy class of the meter under tests Power proportional Pulse output S0-output according to DIN Non-potential contact Other outputs, e.g. KYZ pulse Number of outputs Design Bottom-connected / rectangular design Bottom-connected / round design Socket type according to ANSI standard 19 inch plug-in unit Measurement modes 2 wire active/reactive 3 wire active/reactive true 3 wire reactive cross-connected A/B 4 wire active/reactive 4 wire reactive cross-connected 4 wire apparent Others: Evaluation/Comments Electronic meters CT operated meter 4 Quadrant meter Max. number of Tariff registers:.. Substandard meters Electro mechanical / Electronic meters Today all our test systems are able to test both. Our scanning heads are able to detect LED pulses as well as disk mark revolutions. If the customer has a lot of electromechanical meters SH 11 with automatic adjustment feature can be very useful. Whole current meters Pls. consider max. current of the meter under test to select the right standard.

3 Page 3 / 5 CT operated meters Pls. note, that it is possible to connect high current clamps to PRS / PWS 3.3 / CALPORT 300 / PWS 2.3 genx and CheckMeter 2.3 to test meters from the primary side with consideration of the ratio. In PRS / PWS 3.3 / CALPORT 300 error of common clamps can be compensated. For PRS / CALPORT 300 / PWS 3.3 /PTS 2.3 C and PWS 2.3 genx flexible current sensor FLEX 3000 can be used. These FLEX 3000 are very suitable for on-site tests of primary currents in low voltage networks. PRS / CALPORT 300 /PWS 3.3 /PTS 2.3 C (only current) and PWS 2.3 genx have the possibility to connect high voltage/current sensors for testing in high voltage networks from the primary side. Maximum demand meters All MTE 3-phase standards are able to test maximum demand. 4 Quadrant meters Pls. note, that our standards are able to test both energy directions without changing the connection. Test of other substandard meters K2006 / PRS / PWS 3.3 and CALPORT 300 have power proportional input to calibrate other substandard meters Nominal frequency Our standards are designed for 50 and 60 Hz measurement. 16 2/3 Hz is general possible, but requires a customer specific design. This is important to know for the test report only. Because standards should be tested at the frequency of the later use. Minimum nominal current IEC standard requires for start test 0.5% and lowest load point is 5% of the nominal current. For instance 10/60 A meter will be tested at 50 ma. One of the outstanding features from our standards is the very low measurement current of our error-compensated clamps. We differentiate between 10 A and 100 A clamp. For instance 10 A clamp starts to measure at 5 ma. Power proportional Pulse output Our standards work according to the substandard meter comparison method, which means they compare pulses or disk revolutions of the meter under test with internal power proportional pulses. Pulses or disk revolutions can be detected by scanning head or can be counted by using a snap switch. Another possibility can be S0-pulses or non-potential pulses. On our standards all 3 variants can be connected, although snap switch is not recommended for high accurate tests. Design of the meter This is important to know for adaptation of the scanning head. Our holding device can be adapted to round meters as an option also. For 19 inch plug-in units we have special scanning heads with magnetic probe. Measurement mode For single phase meters we have the standard CheckMeter 2.1 and CheckSystem 2.1 (with internal current source) in our programme. For three phase meters K2006 / PRS / PWS 3.3 and CALPORT 300 have all measurement modes. PWS 2.3 genx and CheckMeter 2.3 have all modes except 3/4wire reactive cross-connected. In case of symmetric net conditions, true measurement mode can be used for it as well.

4 Page 4 / What does the customer intend to do on-site? There are different reasons to test meters on-site: Installation Continuous check after defined time Handling of customer claims Installation During installation it is important to know: Are the meters still o.k. after transportation? This can be done with an accuracy test, for Ferraris meters preferable at a low load point. If no load is available, phantom load is necessary. Is the connection o.k. (phase sequence/current direction)? This can be evaluated with power factor information or power direction in PWS 2.3 genx, CheckMeter 2.3 and CheckMeter 2.1. Vectorial display is very helpful and is available in all 3 phase standards. Is the operating burden of the instrument transformer in the allowed range? PRS / PWS 3.3, CALPORT 300, PWS 2.3 genx, PTS 2.3 C, PTS 3.1 C and PTS 3.3 C can test burden of instrument transformers. Continuous check This can be done to avoid any tampering or to secure working capability. It is recommended to make: Accuracy test Connection check Additional checks, such as visual check of the sealing, comparison of meter number, check of the internal clock, change of the battery. All that checks can be reported in our portables. In case of any claims Due to increasing power consumption and costs, the number of claims increases as well. Beside the tests of the continuous checks also special function tests are necessary to find out the source of the problem 2.3 Which features are required for portables? Phases? 1 phase CheckMeter 2.1 / CheckSystem 2.1 / PTS 3.1 C 3 phase K2006 / PRS / PWS 3.3 / CALPORT 300 / PWS 2.3 genx / CheckMeter 2.3 / CheckSystem 2.3 / PTS 2.3 C / PTS 3.3 C / PTS 400.3PLUS Test load? Coming from the net All standards can be used Using mains voltage and generating current internally CheckSystem 2.1 / CheckSystem 2.3 / PTS 2.3 C Generating current and power factor; voltage from the net CheckSource 2.3 Generating voltage and current 3-phase: PPS / PTS 3.3 C 1-phase: PTS 3.1 C

5 Page 5 / 5 Current measurement? With error compensated clamps 10 A clamps PWS 2.3 genx / PWS A clamps CheckMeter 2.1 / PWS 2.3 genx / CheckMeter 2.3 / PWS 3.3 / CALPORT 300 / PRS / CheckSystem 2.1 / CheckSystem 2.3 / PTS 3.1 C / PTS 2.3 C / PTS 3.3 C / PTS PLUS 1000 A clamps PWS 2.3 genx / PWS 3.3 / CALPORT 300 / PRS / PTS 3.1 C / PTS 2.3 C / PTS PLUS 1000 A clamps (max. 120 A) Flexible clamps up to 3000 A High voltage sensors for current up to 2000 A High voltage sensors for voltage up to 40 kv CheckMeter 2.3 PWS 2.3 genx / PWS 3.3 / CALPORT 300 / PRS / PTS 3.1 C / PTS 2.3 C / PTS PLUS PWS 2.3 genx / PWS 3.3 / CALPORT 300 / PRS / PTS 2.3 C / PTS 3.3 C / PTS PLUS PWS 2.3 genx / PWS 3.3 / CALPORT 300 / PRS / PTS PLUS Direct mode all except CheckMeter 2.1 and CheckMeter 2.3 Auxiliary voltage from the test voltage? For PRS / PWS 3.3 / CALPORT 300 / PTS 2.1 / PTS 2.3 / PWS 2.3 genx / CheckMeter 2.3 / CheckMeter 2.1 For PWS 3.3 and PWS 2.3 genx a battery mode is available. Displaying actual values / Vectorial diagram / Flexible integration time All devices show actual values in one view with freely definable integration period and vectorial display Tests Accuracy test all Energy / Register test all Dial test with controlling phantom load PRS / CheckSystem 2.1 / CheckSystem 2.3 / PTS 3.1 C / PTS 2.3 C / PTS 3.3 C/ CALPORT 300 Maximum demand test all 3 phase standards Burden measurement PRS / PWS 3.3 / CALPORT 300 / PTS 3.1 C / PTS 2.3 C / PTS 3.3 C / PWS 2.3 genx C.T. ratio test PRS / PWS 3.3 / CALPORT 300 / PWS 2.3 genx / PTS 3.1 C / PTS 2.3 C Harmonic measurement K2006 / PWS 3.3 / CALPORT 300 / PWS 2.3 genx / CheckSystem 2.1/ CheckSystem 2.3 / PTS 3.1 C / PTS 2.3 C / PTS 3.3 C/ CheckMeter 2.1 / CheckMeter 2.3 Testing substandard meters K2006 / PRS / PWS 3.3 / CALPORT 300 Accuracy and max. current See table in ppt file