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Portable Single-Phase Watthour Meter Tester
SKU: WT3-1-1-2-1 Category:



Portable Single-Phase Watthour Meter Tester

The MT-1/NT4 is perfect for testing all common residential watthour meters. Using the technology developed for our 3-phase tester, the weight of the MT-1/NT4 is only 5.3 lb.


With the commercial 12S meter, the MT1/NT4 can test two phases simultaneously or separately. The meter under test is entirely controlled by the test socket. No setup wiring is needed.

Best Value

With its specific purpose, the NT4 is the most affordable testing solution for most common single-phase form meters.


Uncompromised accuracy

Three built-in 50A current synthesizers (phantom load) simulate active and reactive load.

Its built-in single-phase Wh/VARh standard will offer you a typical NIST traceable accuracy of ±0.02%.

Easy Setup

Fast setup with no wiring and a dead-front design means your operation is quicker and safer.

Setting-up your test has never been easier.

Technical Specifications

Compatible Meters
Single-Phase 1S, 2S, 3S*, 4S* and 12S
Class 10, 20, 100, 200, 320
Test Socket
Input Voltage 100 – 600VAC
Line Frequency 58 – 62Hz
Power Consumption 75VA (maximum)
Circuit Breakers 2 x 1A (press-to-reset mechanism)
Current Synthesizers
Adjustable Current 0.25 to 50A
Phase Angle (Wh) Unity and 60° Lag
internal 3-phase Watthour Standard
Typical Accuracy ±0.02%
Guaranteed Accuracy ±0.05%
Operation Temperature -4° to 140°F (-20° to 60°C)
Storage Temperature -4° to 140°F (-20° to 60°C)
Physical Dimensions
Test Socket(Diam. x L) 6.9” x 7.7”
Remote Control(Diam. x L) 8.3” x 3.9″ x 1”
Carrying Bag(Diam. x L) 11” x 11” x 8″
Test Socket 5.3 lb
Remote Control(Diam. x L) 0.6 lb
Overall with Carrying Bag(Diam. x L) 8.0 lb
Parts and Labor 2-years limited***
Carrying bag Update cable
User’s manual WTDataOne Software
Quick Start Guide 2 Removable Twist Tabs
Calibration report Remote Control

* May be incompatible with some 3S and 4S form meters.
***Only applicable to units shipped to Canada or USA. 1-year warranty for other countries.