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SFRA45 Sweep Frequency Response Analyzer

The SFRA45 is a Sweep Frequency Response Analyzer with a bandwidth of 5Hz to 45MHz, the SFRA45 offers a fully portable solution for the field of SFRA (Sweep Frequency Response Analysis) which fully complies with IEC60076-18 – Power Transformers Part 18 – Measurement of frequency response.

Featuring an inbuilt colour LCD screen as well as being battery powered, the tablet style instrument can be used with or without PC Software. The dedicated software available (SFRAComm) enables the user to create databases from which historical transformer sweeps can be recalled and compared to current sweeps for analysis. This offers the ability to perform the most common sweep frequency response analysis technique “Fingerprint Comparison” as well as all other comparison techniques.

Product Images

Demystifying SFRA

The Sweep Frequency Response Analyzer simply injects a range of frequencies into a winding of a power transformer, when the power transformer is built correctly with no imperfections and faults the frequency response (of Gain Vs Frequency) plot of that particular type of transformer and winding on that particular transformer should exhibit a particular shape, this “shape” then becomes the transformers “fingerprint”.

Over the course of the transformers lifetime this “fingerprint” can be used in order to detect degradation of the transformer.

When is SFRA performed?

There are three main occasions when SFRA is performed

1. Upon factory quality checking
2. Before a short circuit test
3. Before and After transportation
4. Ongoing scheduled maintenance

Features & Benefits

0.02dB Basic accuracy Frequency range 5Hz to 45MHz
Full Colour VGA Display RS232, LAN and USB
PC Software package included 2Hr Battery Life
Leading Phase Accuracy Truly Portable Measurements
LCR Mode Save Data to external USB
50Ohm or High Impedance Input Scope Function
Save Data to Database for comparison Supplied with all accessories and carry case
Import Formats:- .txt, .csv, .xml, .sfra, .pax Export Formats:- .csv, .xml, .xmlx

Brochures  Documentation 
SFRA45_Brochure PDF, 1,725Kb SFRA45 User Manual v2_10PDF, 825kb
  SFRA45 Comms Manual PDF, 576kb
  SFRA45 – Quick Measurement Guide_v2 PDF, 1,020kb


SFRA45 Options, Software and Accessories

COMMS_ICON Communications Interfaces:
  • Standard: RS232, LAN, USB
PROBE_ICON SFRA45 Accessories:
  • SFRA Connection Clamp Set (Standard)
  • SFRA 18m N4L Cable Reel (Standard)
  • SFRA Earth Braids (Standard)
  • SFRA Earth Clamp set (Standard)
  • USB Memory Stick for data storage (Standard)
  • BNC – BNC Connection Cables + BNC T-Piece (Standard)
  • SFRA45 Flight Case (Standard)
  • Battery Charger (Standard)
  • Vehicle Battery Charger Lead (Standard)
  • SFRAComm Analysis Software (Standard)
  • Customer Cable Reel Length up to 50m (Option)
  • Compliant to IEC60076-18 – Sweep Frequency Response Analysis of Power Transformers (See App note: App_note)
EXTENSION_ICON Port Accessory Options:
  • USB to 9 Pin RS232 Serial Converter
CASES_ICON Carry Cases:
  • SFRA Hard Flight Case – SFRA45 hard carry case, ideal for aircraft hold storage (supplied as standard)
CALIBRATION_ICON Calibration and Documentation:
  • Standard Recalibration – SFRA45
  • Spare set of user manuals – Hard copy of user and communications manual
PC_ICON PC Software (Free of charge):
  • SFRAComm – SFRA PC Interface Software, databasing, graphs, real time data display

Application Notes and Related Articles

For application notes please see the app note section of our Knowledge Database

Frequency Response Analyser
Measurement Magnitude, Gain (CH1/CH2, CH2/CH1),
Gain (dB), Offset Gain (dB), Phase (º)
Frequency Range 5Hz – 45MHz
Gain Accuracy in dB 0.02dB ‹ 50kHz
0.02dB + 0.05dB / MHz < 5MHz
0.1dB + 0.04dB / MHz < 45MHz
Phase Accuracy 0.025º < 10kHz
0.07º + 0.0009º / kHz < 5MHz
5.05º + 0.0001º / kHz < 45MHz
Frequency Source Generator
Measurement Real Time DFT, no missing data
Speed Up to 100 readings per second
Filter Selectable from 0.2 seconds
Resolution 5 or 6 digits
Input Impedance 50 Ohm or 1M Ohm High Impedance (Selectable)
Dynamic Range 120dB
L C R Meter
Functions L,C,R (AC), Q, Tan Delta, Impedance,
Phase – Series or Parallel Circuit
Frequency Range 5Hz to 5MHz
Current Shunt 50R Internal or External
Ranges Inductance
Basic Accuracy 0.5% + 2%/MHz
Sweep Capability All AC functions
Impedance Range 100m Ohm to 100K ohm
True RMS Voltmeter
Channels 2 (Ground Referenced)
Frequency Range 5Hz to 5MHz
Measurement AC, RMS, PEAK, CF, SURGE, dBm
Basic Accuracy (AC) 0.05% range + 0.05% reading + 0.1mV < 1kHz
0.15% range + 0.15% reading + 0.1mV < 10kHz
0.5% range + 0.5% reading + 0.025%/kHz + 0.4mV < 5MHz
Signal Generator
Type Direct Digital Synthesis , Single Frequency or Sweep
Frequency 5Hz to 45MHz
Waveforms Sine, Square, Triangle, Ramp, White Noise
Accuracy Frequency 5ppm over all temperature range
Amplitude ±5% < 10MHz
Amplitude ±10% < 45MHz
Impedance 50 Ohm ± 2%
Scaling 1 x 10^-9 to 1 x 10^9
Output Level 50mVpk to 10Vpk
Inputs 2 x 10Vpk
Connectors Ground referenced BNC
Coupling AC
Max Input 10Vpk from Earth
Input Ranges Peak ranging 1mV, 3mV, 10mV, 30mV, 100mV, 300mV, 1V, 3V, 10V
Scaling 1 x 10^-9 to 1 x 10^9
Ranging Full auto, Up only or Manual
Input Impedance 50 Ohm or 1M Ohm High Impedance Selectable
Instrument Accessories
Probes 2 x Probes
Leads 3 x BNC to BNC (Output, CH1, CH2), RS232, Power
Software CommView, SFRAComm
Documentation Calibration Certificate, User Manual
Newtons4th SFRA Transformer Connection System
Bushing Clamps 2 x Bushing Connection Clamps
BNC Cable Reel N4L 18m Cable reel (Signal, CH1, CH2)
Earth Braid 2 x 5 metre Earthing Braid
Earth Clamps 2
Spare Earth Braid 2 x 500mm
USB Memory Stick 2 GB
Functions FRA, Impedance
Steps Up to 2000 Steps
Window From 50ms with no gap between each log
Memory 1 GB Internal or External USB
Display 5.7″ 1/4VGA Colour high brightness backlit
Dimensions (Instrument) 305H x 230W x 45D mm “Tablet Style”
Weight (Instrument) 2.7Kg
Dimensions (Carry Case) 760mm x 420mm x 150mm
Weight (Full system including case) 14.9Kg
Program Stores 100, Location 1 loaded upon power up
Sweep Stores 2000, all parameters in any sweep function
Import Formats Supported .txt .csv .xlm .sfra .pax
Export Formats Supported .csv .xlm .xmlx
Remote Operation Full Capability, Control and Data
Operating Temperature -5 to 50ºC
Storage Temperature -10 to 60ºC
Relative Humidity Range 20 to 90% Non-Condensing
IP Protection of Inputs and Outputs IP30 – CEI EN 60529
Max Altitude 2,000 Metres
Power Supply 9-18V @ 3A, AC adapter or 12V dc from car or external batteries
Warranty 3 Years