Transformer Turns Ratio Tester

The ATRT-01B S3 is Vanguard’s fourth generation, micro-processor based, single phase, automatic transformer turns-ratio tester. The ATRT-01B S3 uses the IEEE C57.12.90 measuring method to determine the transformer turns-ratio. The transformer turns-ratio is determined by precisely measuring the voltages across the unloaded transformer windings. The ATRT-01B S3’s measuring circuitry self adjusts before each measurement to ensure turns-ratio accuracy. Two selectable test voltages, 4Vac and 40Vac, offer flexibility in testing different types of transformers. The ATRT-01B S3 is battery or AC-powered. The unit can be used continuously for up to 4 hours pwer charge and can be used during charging.

  • Standalone or computer-controlled
  • Inexpensive
  • Displays turns-ratio from 0.8-15,000
  • Calculates turns-ratio percentage error
  • Displays winding polarity and phase angle
  • Displays excitation current
  • Battery or AC-Powered


TYPE Transformer Turns Ratio Tester
PHYSICAL SPECIFICATIONSDimensions: 12” x 10” x 8” (30.4 cm x 25.4 cm x 20.3 cm) Weight: 9 lbs. (4.3 Kg)
INPUT POWER 90 to 240 Vac, 50/60 Hz SLA battery delivering up to 4 hours of continuous operation per charge
RATIO MEASURING RANGE0.8 - 15,000 (5 digit resolution)
TURNS-RATIO ACCURACY40 Vac: 0.8-1,999 (0.1%), 2,000-3,999 (0.25%), 4,000-15,000 (1%) 4 Vac: 0.8-1,999 (0.1%), 2,000-3,999 (0.25%), 4,000-15,000 (2%)
TEST VOLTAGE4 Vac @ 300mA, 40 Vac @ 70mA
PHASE ANGLE MEASUREMENT 0 - 360 degrees, Accuracy ±0.2 degree (±1 digit)
POLARITY READINGIn-Phase or Out-of-Phase indication
EXCITATION CURRENT READING RANGE0-2 Amperes, Accuracy: 2% of reading (±1 mA)
EXCITATION CURRENT READING RANGE0-2 Amperes, Accuracy: 2% of reading (±1 mA)
DISPLAYBack-lit LCD (128 x 64 pixels), viewable in direct sunlight and low light levels
PC SOFTWAREWindows XP/Vista/7 Transformer Analysis Software (included with purchase)
INTERNAL TEST RECORD STORAGE128 records of 33 readings
EXTERNAL TEST RECORD STORAGEUp to 999 test records on external USB Flash drive.
SAFETYDesigned to meet IEC 61010 (1995), UL 61010A-1, and CSA-C22.2 standards
ENVIRONMENTOperating: -10ºC to 50ºC (15ºF to +122ºF) Storage: (-30ºC to 70ºC (-22ºF to +158ºF)
HUMIDITY (MAX)90% RH @ 40˚ C (104˚ F) non-condensing
ALTITUDE (MAX)2000m (6562 ft) to full safety specifications
CABLESOne 15 ft. (4.6m) Single phase cable, one power cord, one cable bag
OPTIONSTransportation Case (Can hold unit and cables)
WARRANTYOne year on parts and labor
ATRT-01 S3 Datasheet (English)
ATRT-01/01B S3 User's Manual (English)
ATRT-01/01B S3 Manual Del Usuario (Español)
ATRT-01/01B S3 User's Manual (Serbian)
TTRA S2 Software Manual (English)