Single Sheet Tester DW-21

Single Sheet Tester DW-21

Digital Iron Loss Tester Model: DW-21 is very accurate single sheet iron loss tester. You can evaluate very accurate watt loss of any electrical steel sheet by feeding it's accurate weight or thickness in the instrument. You can test the sample from 0.2 Tesla to 1.8 Tesla at frequency range from 35Hz to 125Hz. All parameters are digitally programmable using keypad. Separate setting keys are given for three standard induction input. All parameter of source and measure are controlled by micro controller so it gives best in class accuracy of Watt/kg measurement. You have to take sample strip of standard dimension 30mm wide and 305mm long to get better accuracy in measurement. And you can test the sample of any dimension for comparison purpose. Standard sample provided with instrument to ensure the calibration. DW21 is having better than 0.1% accuracy in internal measurement parameters like voltage, current and frequency.

Technical Brochure

Iron Loss Tester, Model: DW-21

User's Manual

Iron Loss Tester, Model: DW-21

Gopal electronics has built the reputation in the market on basis of transparency in sales, easy and quick service, and economic and reliable rates for repairing.
  • The whole product range of Gopal Electronics comes with standard 1 year warranty.
  • For easy warranty claim, you can register your product on our website in case you purchased from any dealer.
  • You can send your instrument by courier to our works for any repairing or calibration service. Your instrument will be inspected first and you will be notified for its repairing or calibration charges. The repairing or calibration process only carried out after the confirmation of customer.
  • The time for repairing or calibration is maximum 48 hours after confirmation.
  • We Ensure your investment secure upto 1 year for any manufacturing defects.

Calibration Service

We provide traceable calibration service according to ISO17025 for all of our product range. Every year you require to calibrate your instruments for your factory certification like ISO, and to maintain quality of your routine test and quality inspection.

Calibration by Gopal Electronics:

  • Our reference meters and standards are traceable to NABL accredited lab or our internal standards as per ISO17025.
  • We have calibration facility of 0.007% (66 ppm) energy accuracy for sinusoidal waveforms.
  • As manufacturer we can change the calibration data and compensate the deviation in each measuring point. So you can get actual calibration not only the comparison report.
  • General Service, replacement of minor parts can be carried out at the same time.
  • Free firmware upgrade is also the part of our calibration process.
  • We can provide calibration at special points which are not included in usual calibration on customer request, like calibration at 0.1 power factor.
  • It takes maximum two days to complete the calibration process after the receipt of your instrument at our factory.
  • Better Accuracy in Single Strip Measurement
  • Microcontroller Based Design
  • Pure sinusoidal source & Measure
  • Long term stability and accuracy maintain
  • Password protected calibration
  • 24 key feather touch keypad for easy operation
  • Digital Setting for all data [Hz, B, Th, Dn etc.]
  • Direct key to enter three usual induction
  • 20x4 Character LCD Display
  • Direct reading of Watt/kg & Watt/lb
  • Connector type low loss probe
  • Three mode for easy and accurate operation
  • Last setting save in nonvolatile memory
  • Standard & Big size of sample possible to test
  • Self demagnetizing process
  • User friendly operation and portable size

Operation Theory

DW-21 is provided with a stroboscopic probe when placed on specimen, closes the magnetic path between probe and specimen. Probe has two coils one is primary and second is secondary (like transformer). When power applied to primary coil and detected by secondary coil appropriate to specimen data and measure voltage, current and power. Then measured data calculated by microcontroller appropriate to specimen's data (core area and weight) and directly displayed on LCD Watt/Kg and Watt/lb.

Scope of Measurement

- Watt/kg & Watt/Lb of Electrical steel sheet

  • Dimension of Main Unit = H 110mm + Leg, L 280 mm, W 230 mm Approx.
  • Dimension of Probe = H 72 mm, L 113mm, W 50mm
  • Weight of Main Unit = 3.870 Kg. Approx.
  • Weight of Probe = 872 gm Approx
  • Dimension of final carton = H 390mm, L 390mm, W 240mm Aprox
  • Weight of final carton = 5.0 Kg. Approx.
  • Power Supply = AC 230V / 110V, 50/60Hz (any one) 20VA
  • Source Capacity = 1.5V x 300mA Sine wave
  • Frequency Range = 35Hz to 125Hz
  • Measuring Range = 0.1 to 22 Watt/kg and 10 Watt/lb
  • Magnetic Flux Density Range = 0.2 to 1.8 Tesla (weber/square meter) or limited to source capacity


  • Volt Meter = ± 0.1% FSD True RMS Volt
  • Amp. Meter = ± 0.1% FSD True RMS
  • Power Meter = ± 0.1% FSD @ 1PF
  • Frequency = ± 0.1% which Instrument can set
  • Watt/kg (Iron Loss) = Refer comparison table


  • Standard Specimen Size = 30x305 mm to 30x280 mm
  • Non Standard Specimen Size = More than 30x115 mm for comparisons
  • Specimen Thickness Range = 0.1 to 0.75mm
  • DW21 Main Unit
  • Probe
  • Probe connection wire
  • Standard sample for varification of calibration
  • Calibration Certificate
  • Mains Cord
  • Softcopy User's Manual in CD