DJF Series · IEC 60270:2000

Partial Discharge Tester: 1-to-4 Channel Digital PD Detectors & HV Test Systems

Shanghai DEMIKS Electric Power Technology Co., LTD builds digital partial discharge testers and PD-free high-voltage test systems. Each electrical partial discharge tester measures picocoulomb (pC) apparent charge in transformers, power cables, switchgear, and motors. Send your specimen voltage and capacitance to receive an itemized engineering quote within 24 hours.

  • Engineer-reviewed quote within 24 hours
  • Benchtop instruments ship in 7–15 working days
  • 0.1 pC sensitivity per IEC 60270:2000
  • 1 set minimum order quantity (MOQ)
Request 24-Hour Engineering Quote Launch PD kVA & Channel Sizing Calculator
DEMIKS 1-to-4 channel digital partial discharge tester and PD-free high-voltage test system

Applications Direct circuit review for FATs, OEM test bays, and Substation commissioning crews.

Deliverables Every partial discharge measurement unit ships with an ex-factory inspection report, certificate of conformity, English operation manual, and 12-month warranty card.

Specifications

Digital Partial Discharge Tester Capabilities at a Glance

Our offline partial discharge test equipment employs multi-channel digital pulse capture with low-noise AC excitation up to 1000 kV. Verified operating limits of the DJF instrument series are shown below.

Signal Acquisition

  • Channel Architecture: 1-to-4 synchronous channels (DJF-126, DJF-124, DJF-125, DJF-127)
  • Apparent Charge Range: 0.1 pC sensitivity; 0.1 pC to 100,000 pC (up to 10,000 nC on PDIV cabin)
  • Digitizer & Filter: 12-bit ADC at 1 / 5 / 10 MHz; 10 kHz to 1 MHz digital bandpass
  • Specimen Capacitance: 6 pF to 250 µF across bushings, transformers, cables, and stator coils

HV Source & Delivery

  • System Noise Floor: ≤5 pC rated-voltage background noise; ≤10% nonlinear error
  • Matched HV Sources: 1 kVA to 1000 kVA, AC 0 to 1000 kV oil-immersed and SF6 PD-free transformers
  • Standard Lead Time: 7–15 working days benchtop; 20–30 working days custom HV systems
  • Order & Export Support: 1 set MOQ; exported to 8 countries with paid on-site commissioning

Digital Partial Discharge Detector & Analyzer Model Lineup

Offline IEC 60270 benchtop analyzers and handheld ultrasonic, TEV, or UHF spot sensors serve distinct diagnostic roles. Handheld acoustic cameras screen live switchgear for surface corona without picocoulomb calibration. Factory acceptance contracts require calibrated readings of apparent charge value in pC under controlled AC overvoltage.

DJF-126 Four-Channel Benchtop Digital PD Tester

The DJF-126 4-channel benchtop digital partial discharge tester delivers 0.1 pC sensitivity across a 0.1 pC to 100,000 pC range. Its 12-bit digitizer runs at selectable 1 MHz / 5 MHz / 10 MHz sampling rates with a 10 kHz to 1 MHz digital filter. Six gain gears (-40 dB to 60 dB) and 50–500 Hz sync cover 6 pF to 250 µF specimens.

DJF-126 Four-Channel Benchtop Digital PD Tester

DJF-124, DJF-124NT & DJF-127 Touchscreen PD Detectors

DJF-124, DJF-124NT, and DJF-127 digital partial discharge detectors replace CRT oscilloscope tubes and physical knobs with a 10.1-inch touch screen. Nine selectable frequency-band combinations and hardware-plus-software anti-interference filtering suppress VFD noise where background interference signals often exceed the acceptance level. Direct calibrated pC pulse readout pairs with an independent accumulation timer.

DJF-124, DJF-124NT and DJF-127 Touchscreen PD Detectors

DJF-125 & 124T PD Meters with Industrial PC Control

Systems pairing DJF-125 or 124T partial discharge meters with industrial embedded-PC control support automated high-voltage testing. The control package handles multi-stage step-up and step-down voltage profiles, real-time curve plotting, and A4 report export in Microsoft Word or Excel.

DJF-125 and 124T PD Meters with Industrial PC Control

DJF-1kVA-7.5kV Shielded-Cabin PDIV & PDEV Detector

The DJF-1kVA-7.5kV integrated shielded-cabin PDIV and PDEV detector tests motor windings and insulating materials from AC 500 V to 7.5 kV. It spans 0.1 pC to 10,000 nC with 2% voltage/current accuracy and more than 20 programmable voltage stages. An electric shielding door holds internal cabin background noise at <5 pC.

DJF-1kVA-7.5kV Shielded-Cabin PDIV and PDEV Detector
Request DJF Detector & System Quotation

Oil-Immersed Test Systems with Industrial PC Control

These systems use an oil-immersed test transformer and automatic industrial PC control for programmed voltage ramps and report export. Specify the detector variant when placing an order for a model offering more than one detector.

System Model Nominal Capacity / Voltage Configuration
DJF-1kVA-5kV 1 kVA / 5 kV Industrial PC, oil-immersed transformer, 124-series PD detector
DJF-10kVA-50kV (DJF-124-10kVA-50kV) 10 kVA / 50 kV Industrial PC, oil-immersed transformer, 124-series PD detector
DJF-10kVA-100kV 10 kVA / 100 kV Industrial PC, oil-immersed transformer, 124NT PD detector
DJF-10kVA-120kV 10 kVA / 120 kV Industrial PC, oil-immersed transformer, 124-series PD detector
DJF-10kVA-120kV 10 kVA / 120 kV Industrial PC, oil-immersed transformer, 124NT PD detector
DJF-10kVA-120kV 10 kVA / 120 kV Industrial PC, oil-immersed transformer, 125-series PD detector
DJF-15kVA-150kV 15 kVA / 150 kV Industrial PC, oil-immersed transformer, 125-series PD detector
DJF-20kVA-100kV 20 kVA / 100 kV Industrial PC, oil-immersed transformer, 124-series PD detector
DJF-20kVA-150kV 20 kVA / 150 kV Industrial PC, oil-immersed transformer, 124-series PD detector
DJF-25kVA-250kV 25 kVA / 250 kV Industrial PC, oil-immersed transformer, 126-series PD detector
DJF-30kVA-150kV 30 kVA / 150 kV Industrial PC, oil-immersed transformer, 124-series PD detector
DJF-50kVA-150kV 50 kVA / 150 kV Industrial PC, oil-immersed transformer, 125-series PD detector
DJF-50kVA-250kV 50 kVA / 250 kV Industrial PC, oil-immersed transformer, 124-series PD detector
DJF-150kVA-30kV 150 kVA / 30 kV Industrial PC, oil-immersed transformer, touchscreen PD detector with model to be confirmed
DJF-250kVA-50kV 250 kVA / 50 kV Industrial PC, oil-immersed transformer, touchscreen PD detector with model to be confirmed

Motorized, Gas-Filled and Multichannel Test Systems

System Model Nominal Capacity / Voltage Configuration
DJF-10kVA-100kV 10 kVA / 100 kV Automatic industrial PC control, gas-filled transformer, 124-series PD detector
DJF-10kVA-100kV 10 kVA / 100 kV Motorized control, oil-immersed transformer, 124T PD detector
DJF-124-15kVA-150kV 15 kVA / 150 kV Motorized control, oil-immersed transformer, new-style 124 PD detector
DJF-124-20kVA-150kV (DJF-20kVA-150kV) 20 kVA / 150 kV Fully automatic industrial PC control and touchscreen PD detector. Confirm transformer insulation and detector model.
DJF-50kVA-100kV 50 kVA / 100 kV AC withstand and partial discharge test system. Confirm controller, transformer insulation and detector.
DJF-126-50kVA-200kV 50 kVA / 200 kV Four-channel digital PD measurement
DJF-124-100kVA-100kV 100 kVA / 100 kV Integrated electrical push-button controls and DJF-124 touchscreen PD detector
DJF-127-100kVA-100kV 100 kVA / 100 kV Integrated electrical push-button controls and DJF-127 touchscreen PD detector

Confirm the rated test voltage when requesting either 100 kVA model and the available control modes for the two motorized oil-immersed configurations.

Smart Integrated Power-Frequency Test Systems

Use the full DJF model code and configuration when requesting a quote. Some systems share the same kVA and kV ratings but use different controls, transformer insulation or PD detectors.

System Model Nominal Capacity / Voltage Configuration
DJF-10kVA-100kV 10 kVA / 100 kV Smart integrated automatic control with a 10.1-inch touchscreen PD instrument
DJF-15kVA-100kV 15 kVA / 100 kV Smart integrated automatic control with a 10.1-inch touchscreen PD instrument
DJF-30kVA-150kV 30 kVA / 150 kV Smart integrated automatic control with a 10.1-inch touchscreen PD instrument

Shielded-Chamber and PDIV/PDEV Test Systems

The 7.5 kV system measures partial discharge inception and extinction voltages (PDIV and PDEV). It supports programmed voltage stages and hold times within its integrated shielded chamber.

System Model Nominal Capacity / Voltage Configuration
DJF-1kVA-7.5kV 1 kVA / 7.5 kV Automatic industrial PC control, electrically operated shielded chamber and digital PD instrument
DJF-124-1kVA-10kV 1 kVA / 10 kV Automatic industrial PC control, shielded chamber and 124-series touchscreen PD detector
DJF-5kVA-5kV 5 kVA / 5 kV Automatic industrial PC control, shielded chamber and touchscreen PD detector

Test Transformers and Control Consoles

The YDW-30kVA-5kV is a 30 kVA / 5 kV oil-insulated, PD-free power-frequency test transformer. The motorized control console with a new-style 124 PD detector is supporting equipment for a compatible test transformer. For the YDW-50/100 (YDW-50-100) transformer, specify the nameplate rating and matching control package in your inquiry.

When requesting a quotation, provide the system model and configuration, test object and its capacitance, required AC test voltage and hold time, number of measurement channels, and any shielding or PD acceptance requirements.

Comparison: DEMIKS Offline IEC 60270 Systems vs Component & Spot Testers

Architecture Voltage Envelope Output Unit Primary Engineering Role
DEMIKS DJF-126 / 124 + YDW PD-Free System AC 0.5 kV to 1000 kV (1–1000 kVA) Calibrated pC & nC per IEC 60270 Factory acceptance testing and commissioning of HV transformers, cables, GIS, and motors
Low-Voltage Component Hipot + PD Tester (Chroma 19501 class) AC 0.1 kV to 10 kV pC / nC Benchtop optocouplers, relays, and dry components; cannot energize MV/HV power assets
Handheld Ultrasonic / Acoustic Camera / TEV Probe (Fluke, EA Technology, Doble survey tools) Energized line voltage (non-contact) dBµV / acoustic dB (uncalibrated) Live walkdowns for external corona and surface tracking; not interchangeable with IEC 60270 FAT

Traditional modular architectures often source detectors, quadripoles, and high-voltage elements from different vendors. Specify the detector, coupling capacitor and PD-free transformer together so the measurement loop is matched to the test object.

  • Simultaneous three-phase and neutral bushing capture on the DJF-126 accelerates transformer partial discharge test and partial discharge detection cycles.
  • Partial discharge displays separate discharges in the internal cavity from the external corona.
  • Automated voltage ramps capture the inception and extinction of discharge.

Related Cable PD Equipment and Test-Bay Components

A complete test bay may require a separate voltage source and voltage-measurement equipment. Request these in addition to the PD detector to ensure the entire measurement circuit is included in the quotation.

Model or Product Family Role in the Test Setup Selection Boundary
CBA-6 (confirm order designation) Cable PD detector specification: compatibility with VLF, power-frequency and series-resonant voltage sources; 0.1 pC PD resolution, 14-bit sampling and Ethernet interface. Confirm the supplied model designation, voltage-source package and operating limits in the quotation.
VLF-PD Very-low-frequency cable partial discharge test equipment, with PD-Suite software described in the operating manual. A separate cable PD family. Specify the required test voltage, cable length and cable capacitance; obtain the offered unit's complete rating and configuration.
DTC-104D-50kVA + YDW-50kVA-150kV Intelligent split control console paired with a PD-free test transformer; nominal transformer designation: 50 kVA / 150 kV. High-voltage excitation equipment. A PD measurement package must be specified separately.
RCF-50kV, RCF-100kV, RCF-200kV AC/DC high-voltage dividers for voltage measurement. Select the divider for the test voltage and measurement arrangement; these models are not PD detectors.
DFY-50kV, DFY-80kV High-voltage divider designations. Request the divider ratio, accuracy and AC/DC suitability before specifying either model.
Submit HV Test Parameters & Request Configuration

High-Voltage Test Assets & Insulation Specimens Supported

Early detection of insulation degradation is critical and requires tight tolerance coupling capacitance, filtering, and reactive charging currents. Below are 15 medium-high voltage elements configured by our engineers.

DEMIKS DJF-25kVA 250kV High-Voltage Partial Discharge Test System

  • 1.Liquid-Immersed Power Transformers

    Asset Class:35 kV to 500 kV substation & generator step-up units

    Diagnostic Target:Catches pressboard delamination and winding cavity discharge faster than dissolved gas analysis alone.

    Circuit Match:DJF-126 4-channel analyzer via bushing tap sensors at 100–500 kHz per IEC 60076-3 and IEEE C57.113.

    Cost Tier:$$$ – $$$$

    Ship Window:8–20 working days (instrument + bushing tap adapters)

  • 2.Cast-Resin Dry-Type Transformers

    Asset Class:6 kV to 35 kV indoor distribution & traction units

    Diagnostic Target:Detects epoxy casting voids where trapped air suffers 2.3× higher electric field stress.

    Circuit Match:DJF-124NT or DJF-126 with three-phase PD-free coupling capacitors for ≤10 pC routine acceptance.

    Cost Tier:$$ – $$$

    Ship Window:7–15 working days (detector) / 20–30 working days (turnkey bay)

  • 3.Extruded XLPE Power Cables & Reels

    Asset Class:10 kV to 400 kV factory reels & underground circuits

    Diagnostic Target:Routine cable pd testing isolates insulation protrusions and voids at <5–10 pC per IEC 60885-3 and IEC 60840.

    Circuit Match:DJF-126 (50–500 Hz sync) paired with YDW PD-free transformer or variable-frequency resonant source.

    Cost Tier:$$$ – $$$$$

    Ship Window:20–30 working days for matched HV cable test bays

  • 4.Cable Terminations & Pre-Molded Joints

    Asset Class:15 kV to 220 kV elastomeric & heat-shrink accessories

    Diagnostic Target:In CIGRE's 26,494 km survey, terminations and joints account for most commissioning failures (2.8% and 0.75% vs 0.01% body).

    Circuit Match:DJF-124 or DJF-126 with 1000 pF PD-free coupling capacitor and AN quadripole impedance.

    Cost Tier:$$ – $$$

    Ship Window:8–20 working days

  • 5.Gas-Insulated Switchgear (GIS) Compartments

    Asset Class:72.5 kV to 550 kV SF6 & clean-air GIS bays

    Diagnostic Target:Flags free metallic particles, shield corona, and epoxy spacer voids prior to grid energization.

    Circuit Match:SF6 gas-insulated YDW PD-free transformer (<50°C rise, ≤5 pC) + DJF-127 touchscreen detector.

    Cost Tier:$$$$ – $$$$$

    Ship Window:20–30 working days

  • 6.Medium-Voltage Metal-Clad Switchgear

    Asset Class:3.6 kV to 40.5 kV vacuum breaker panels

    Diagnostic Target:Reveals busbar spout tracking and epoxy shrinkage during combined AC hipot and PD tests.

    Circuit Match:DJF-125 console with 50 kVA / 100 kV oil-immersed PD-free AC hipot tester and A4 report export.

    Cost Tier:$$ – $$$

    Ship Window:20–30 working days

  • 7.High-Voltage Rotating Machine Stator Windings

    Asset Class:6 kV to 24 kV hydro, turbo, & industrial electric motor stators

    Diagnostic Target:Tracks mica-epoxy groundwall delamination, slot discharge, and grading paint deterioration per IEC 60034-27-1.

    Circuit Match:DJF-126 4-channel detector supporting high capacitance loads up to 250 µF.

    Cost Tier:$$$

    Ship Window:8–20 working days

  • 8.EV Hairpin Stators & Inverter-Fed Motor Coils

    Asset Class:400 V to 1000 V SiC PWM drive windings (tested up to 7.5 kV AC)

    Diagnostic Target:Verifies PWM voltage overshoots stay below turn-to-turn enamel PDIV limits per IEC 60034-18-41.

    Circuit Match:DJF-1kVA-7.5kV shielded-cabin PDIV/PDEV detector (<5 pC background, >20 programmable stages).

    Cost Tier:$$

    Ship Window:7–15 working days

  • 9.Instrument Transformers (CT & PT / CVT)

    Asset Class:10 kV to 220 kV inductive & capacitive instrument units

    Diagnostic Target:Confirms oil-paper or cast-resin primary insulation health immediately after induced pre-stress.

    Circuit Match:DJF-124 touchscreen detector with 9-band interference filtering and independent timer.

    Cost Tier:$$ – $$$

    Ship Window:8–20 working days

  • 10.High-Voltage Condenser Bushings

    Asset Class:35 kV to 500 kV OIP & RIP transformer bushings

    Diagnostic Target:Detects foil-edge partial discharge activity and moisture ingress in 150 pF to 1,200 pF cores.

    Circuit Match:DJF-126 at 0.1 pC sensitivity with test-tap quadripole coupling.

    Cost Tier:$$$ – $$$$

    Ship Window:20–30 working days

  • 11.Metal-Oxide Surge Arresters & Varistors

    Asset Class:10 kV to 330 kV polymeric & porcelain station arresters

    Diagnostic Target:Separates internal radial air-gap micro-discharges from resistive ZnO leakage current.

    Circuit Match:DJF-124NT + low-capacitance PD-free transformer (10–30 kVA, ≤5 pC).

    Cost Tier:$$

    Ship Window:8–20 working days

  • 12.Power Capacitors & Coupling Capacitors

    Asset Class:6 kV to 110 kV shunt banks & carrier coupling units

    Diagnostic Target:Verifies film-foil edges remain free of ionization across high capacitance banks up to 250 µF.

    Circuit Match:DJF-126 high-attenuation gain gear (-40 dB to 60 dB) with high-current input impedance.

    Cost Tier:$$$

    Ship Window:8–20 working days

  • 13.Epoxy Post Insulators & Vacuum Interrupters

    Asset Class:12 kV to 40.5 kV switchgear insulation components

    Diagnostic Target:Screens out micro-cracks around metal inserts that cause flashover in humid service.

    Circuit Match:DJF-125 automated console with motorized shielded enclosure (<5 pC).

    Cost Tier:$$

    Ship Window:20–30 working days

  • 14.Enameled Magnet Wire, Polyimide Films & Potting Resins

    Asset Class:AC 500 V to 7.5 kV twisted-pair & sheet dielectric samples

    Diagnostic Target:Defines film thickness and resin cure rules needed to insulate traction and aerospace coils.

    Circuit Match:DJF-1kVA-7.5kV integrated shielded-cabin PDIV/PDEV tester (6 pF+ specimen support).

    Cost Tier:$ – $$

    Ship Window:7–15 working days

15.Custom Multi-Terminal or Ultra-High-Voltage Specimens

Traction transformers, HVDC valve reactors, and submarine cable joints require custom coupling impedances and corona-shielded high-voltage leads. Send your device under test capacitance, test voltage, and target pC limit for a circuit layout within 24 hours.

Send Specimen Specs for Sizing

PD-Free Excitation Sources, Coupling Networks & Signal Conditioning

Contrary to the common assumption that a standalone "<5 pC transformer" guarantees a quiet bay, partial discharge measurements integrate noise across the entire HV loop. A high capacitance DUT can exceed the available current of an undersized source because charging current scales as I = 2πfCV.

"Specimen capacitance from 6 pF bushings to 250 µF stator banks dictates both reactive kVA demand and transformer cooling medium. Remember, a partial discharge test does not replace AC withstand; our YDW series performs a dielectric hipot and <5 pC check simultaneously."

High-Voltage Test Systems Engineering Team, DEMIKS (Shanghai Lingang)

Based on specified test voltage, insulated PD-free transformers are either oil-immersed or with SF6 gas, depending on the requirement.

  • Oil-Immersed PD-Free Test Transformer (YDW-Oil)
    1 kVA to 1000 kVA, AC 0 to 1000 kV; <55°C surface rise; ≤5 pC at rated kV
    High thermal mass for permanent factory bays; heavier floor load than gas cylinders
    DEMIKS factory-matched
  • SF6 Gas-Insulated PD-Free Transformer (YDW-GTB)
    1 kVA to 1000 kVA, AC 0 to 1000 kV; <50°C surface rise; ≤5 pC at rated kV
    Lighter crane weight and oil-free cleanliness for GIS halls and mobile trailers; higher unit cost
    DEMIKS factory-matched
  • Coupling Capacitor Network (Ck)
    500 pF / 1000 pF / 2000 pF, rated up to 1000 kV at ≤2–5 pC
    Low-inductance path for fast PD pulses; higher Ck/Ca ratio boosts pC sensitivity
    DEMIKS factory-matched
  • Measuring Impedance Quadripole (AN / Zm)
    Matched input units for 6 pF to 250 µF specimen capacitance
    Converts nanosecond PD current pulses into filtered voltage signals while shunting power current
    Included with DJF testers
  • Low-Voltage Isolation Filter & Corona Rings
    Mains EMI isolation + spun-aluminum toroids
    Blocks workshop VFD harmonics on the LV bus and suppresses air corona on HV leads
    Included in turnkey bays
  • 9-Band Hardware + Digital Bandpass Conditioning
    10 kHz to 1 MHz digital filter; 9 band combinations; -40 dB to 60 dB gain
    Shifts passband clear of local AM broadcast pickup and thyristor switching spikes
    Built into DJF-124 / 126 / 127
  • Motorized Shielded Test Cabin
    AC 500 V to 7.5 kV (or custom MV enclosure); <5 pC background
    Avoids full Faraday room construction when testing motor coils and epoxy parts
    DJF-1kVA-7.5kV integrated
  • Step-Pulse Charge Calibrator
    Direct pC charge injection across DUT terminals per IEC 60270
    Locks scale factor before HV energization to compensate capacitive divider attenuation
    Included with DJF testers