MT-1/WT1 | Single-phase Wh Meter Tester
Wireless High-Accuracy Portable Field tester

The MT-1/WT1 provides safe and fast results, no “strings” attached…
Meter technicians can accurately test residential, commercial or industrial electricity meters on site in mere minutes.
The MT-1/WT1 has a built-in two-phase phantom load consisting of synthesized 50 A current sources and a two-phase electronic standard with a typical accuracy of ±0.02% and a guaranteed accuracy of ±0.05%. It comes with a complete calibration report certifying measurement accuracy across its entire operating range.
Big technological leaps come in small packages…
Weight: 5.7 lb. | Size: 6.9″ X 6.7″
SKU: WT1
The MT-1/WT1 provides safe and fast results, no “strings” attached…
Meter technicians can accurately test residential, commercial or industrial electricity meters on site in mere minutes.
The MT-1/WT1 has a built-in two-phase phantom load consisting of synthesized 50 A current sources and a two-phase electronic standard with a typical accuracy of ±0.02% and a guaranteed accuracy of ±0.05%. It comes with a complete calibration report certifying measurement accuracy across its entire operating range.
Big technological leaps come in small packages…
Weight: 5.7 lb. | Size: 6.9″ X 6.7″
SKU: WT1

MT-1/WT1 | Description
Easily acquire accurate measurements wirelessly
Like all our wireless products, the meter tester can be paired with a mobile device in seconds by scanning its QR code, when using Probewell Connect 2.0.
Compatible Forms Supported by the MT-1/WT1 meter tester
Easily configurable with twist & lock removable tabs, you will be able to test both solid state and electromechanical meters.
Single-phase: 1S, 2S, 3S, 4S, 12S(N) and 25S
Class: 10, 20, 100, 200, 320**
Meter Form |
1S |
2S |
3S |
4S |
5S |
6S |
8S |
9S |
12S |
14S |
15S |
16S |
Aclara® Fitzall ™ |
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35S |
36S |
25S |
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45S |
46S |
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Meter Tester |
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Self-Contained |
CT-Rated |
Self-Contained |
CT-Rated |
Self-Contained |
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Available tests
Quick Test
Full Test
Custom Test
Line Monitor
Demand Test
Creep Test
KYZ Test
Manual / Tracking Test
4 Quad Test (VARh)
4 Quad Test (wh)
MT-1/WT1 | Description

Easily acquire accurate measurements wirelessly
Like all our wireless products, the meter tester can be paired with a mobile device in seconds by scanning its QR code, when using Probewell Connect 2.0.
Available tests
Quick Test
Full Test
Custom Test
Line Monitor
Demand Test
Creep Test
KYZ Test
Manual / Tracking Test
4 Quad Test (VARh)
4 Quad Test (wh)
Compatible Forms Supported by the MT-1/WT1 meter tester
Easily configurable with twist & lock removable tabs, you will be able to test both solid state and electromechanical meters.
Single-phase:
1S, 2S, 3S, 4S, 12S(N) and 25S
Class: 10, 20, 100, 200, 320**
MT-1/WT1 | Technical Specifications

COMPATIBLE METERS | |
Single-Phase | 1S, 2S, 3S*, 4S, 5S, 12S(N), 25S and 45S |
Class | 10, 20, 100, 200, 320** |
COMPATIBLE DEVICES | |
Operating systems | IOS®, Android®, Windows® |
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 |
Phase Angle (VARh) | 90° and 30° Lag |
INTERNAL 3-PHASE WATTHOUR STANDARD | |
Typical Accuracy | ±0.02% |
Guaranteed Accuracy | ±0.05% |
ENVIRONMENT | |
Operation Temperature | -4° to 140°F (-20° to 60°C) |
Storage Temperature | -4° to 140°F (-20° to 60°C) |
Humidity | 5% to 95% (non condensing) |
PHYSICAL DIMENSIONS | |
Test Socket (Diam. x L) | 6.9” x 7.7” |
WEIGHT | |
Test Socket | 6.4 lb |
WARRANTY | |
Parts and Labor | 2-years limited*** |
ADVANCED FEATURES | |
Wh/VARh | |
Reverse Flow Test for bidirectional meters | |
Line Monitor | |
KW Demand Test | |
Creep Test | |
INCLUDED | |
Carrying bag | Update cable |
User’s manual | Probewell Connect App. |
Quick Start Guide | 2 Removable Twist Tabs |
Calibration report |
*An adapter is required to verify 3S Sensus Meter.
**An adapter may be required depending on the meter installation.
***Only applicable to units shipped to Canada or USA. 1-year warranty for other countries.
Probewell Support Portal

Help yourself to our product documentation to rapidly find answers to your questions and troubleshoot your product.

Trade-in & Trade-Up
If you own an older-generation Probewell product, you are automatically eligible for our trade-in program.
Trade in your old meter tester and get up to 1,000 USD* off the purchase of any of our newer models.
*US customers only. If you are a customer from outside the United States, please contact Probewell.
Trade-in and Trade-Up
If you own an older-generation Probewell product, you are automatically eligible for our trade-in program.
Trade in your old meter tester and get up to 1,000 USD* off the purchase of any of our newer models.
*US customers only. If you are a customer from outside the United States, please contact Probewell.