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Frequency Response Analyzer Accessories

The N4L range of frequency response analyzers can be used in a wide range of applications, in reflection of this we have developed various accessories to enable accurate, reliable and convenient measurement.

Injection Transformers

Frequency response analyzer injection transformer

The PSM1700 and PSM1735 feature ground referenced generators, as a result there is a requirement to isolate the injected perturbation signal from ground so that the feedback loop is not shorted to the ground plane.  This action is performed by an injection transformer and N4L have designed numerous injection transformers to meet a range of frequencies and voltages.

Model  Frequency Range   Voltage Rating   Turns Ratio  Connectors Datasheet
Standard Injection Transformer10Hz to 200kHz50V6.3:1BNC Input, Isolated BNC OutputPSM Injection Transformer Range – Datasheet
HF Injection Transformer500Hz to 35MHz50V2.3:1BNC Input, Isolated BNC Output
HV Injection Transformer5Hz to 15MHz1KV CATII2.3:1BNC Input, 2x 4mm Safety Connector Output
Low Frequency Injection ModuleDC to 100kHz600V CATII3.1:1BNC Input, 2x 4mm Safety Connector Output

Impedance Measurementres

LCR Active Head

LCR Meter Active Head

The LCR Active Head converts the PSM1700/PSM1735 into a High Performance LCR Meter with true 4-Wire connections that are taken directly to the component without the need for external shunts. Buffering, amplification and selectable shunts provide LCR measurement over a wide frequency and impedance range.

Frequency Range10μHz to 5MHz
Inductance100nH to 10kH
Capacitance10pF to 1000μF
Resistance10mΩ to 100MΩ
Basic Accuracy
PSM1700/350.2% < 1kHz
PSM17000.5% + 0.005% / kHz < 1MHz
PSM17350.5% + 0.005% / kHz < 5MHz
LCR Active Head Supplied With:BNC to Kelvin Clip Lead Set (Power and Comms via hard wired Auxiliary Lead)
DatasheetLCR Active Head + IAI/IAI2 – Datasheet

IAI Kelvin Fixture

The N4L Impedance Analyzer range offers high accuracy, high frequency LCR measurement. To accompany the IAI and IAI2 we have developed an IAI Kelvin Fixture. This fixture features four contact plates providing true four wire impedance measurement.

Frequency RangeDC to 35MHz
DatasheetIAI Kelvin Fixture – Datasheet

IAI 22mm Adaptor

22mm adapter for N4L impedance analyzers

The N4L Impedance Analyzer range are designed with BNC connector spacing that do not match the spacing of some third-party test fixtures on the market. Our IAI 22mm Adaptor converts the standard IAI spacing to 22mm spacing, this simplifies connection to third-party test fixtures with 22mm spacing.

DatasheetIAI 22mm Adaptor


N4L LSF/HSF External Signal Filters

N4L LSF/HSF Filters are a range of filters specifically designed for use with the N4L range of HF current shunts.
Available as 5 kHz low pass and 50 kHz low pass for improved signal to noise ratio.
These compact filters are fitted with safety BNC connectors to enable direct connection to the PPA external inputs.
The HSF10m filter has been designed for DC blocking and is designed to be used in pairs with our BATT470m EIS (Electrochemical Impedance Spectroscopy)

ModelRoll off frequency (-3dB)Specification Data
LSF05-3dB@ 5kHz ± 1kHz Low PassLSF & HSF – Datasheet
LSF50-3dB@ 50kHz ± 10kHz Low Pass
HSF10m -3dB@ 10mHz ± 2mHz
High Pass

Electrochemical Impedance Spectroscopy

Batt470m - EIS Interface (Electrochemical Impedance Spectroscopy)

The BATT470m electrochemical impedance analysis interface (EIS) provides an easy to use battery/cell impedance test platform for the electrochemical industry. Utilizing the highly accurate PSM3750 frequency response analyzer from N4L, the BATT470 provides impedance measurement of batteries/cells up to 200V DC.


DatasheetBATT470m – Datasheet

Current Measurement (External)

N4L HFR High Frequency Current Shunts

If external current measurement is necessary for impedance measurement, for example if a test setup utilising an LPA Laboratory Power Amplifier for signal generation is employed. The HF series shunts provide an accurate current sensing solution for many wideband measurement applications up to 20Arms. Utilising an innovative design that is unique to N4L, each shunt will maintain its specified resistance over a frequency range from DC to 1MHz without exhibiting the phase shift normally associated with resistive shunts

ModelCurrent RatingSpecification Data
HFR01020ArmsHFR Shunts – PSM – Datasheet
HF01R1 Arms

AC Current Clamps

1000Arms AC Current Clamp

As an alternative to selecting an HFm current shunt for external current measurement in impedance applications is our AC Current Clamp range. These clamps provide current measurement up to 3,000A (P32-UE) with an upper bandwidth of 15kHz (SMUB), providing accurate measurement of an AC signal over a wide bandwidth. Typical applications include impedance measurement of electrochemical cells where high DC current bias is present, the AC responding current clamp will reject the DC bias current and reliable accurate measurement of the AC perturbation current is recorded.

ModelCurrent RatingDatasheet
M3-UB-50100mA → 50AM3 UB 50 – 1V
M3-U-1001 → 100AM3 U 100 – 1V
S-UE-2001 → 200AS UE 200 – 1V
S-UE-2501 → 250/500/1000AS UE 250 500 1000
US-UE-10001 → 1,000AUS UE 1000 - 1V
SM-UE-10000.5 → 1,000ASM UE 1000 - 1V
SM-UB-10000.5 → 1,000ASM UB 1000 - 1V
P32-UE-10005 → 1,000AP32 UE 1000 - 1V
P32-UE-30005 → 3,000AP32 UE 3000 - 1V

High Voltage Measurement

TT-HV-250 High Voltage Probe (2.5kVpk)

2500Vpk voltage probe

For High voltage applications, we recommend the PSM3750 frequency response analyzer, for voltages above this level an attenuator is required and the TT-HV-250 provides measurement up to 2.5kV

Voltage RatingAttenuationBandwidthSpecification Data
2.5kVpk100:1300MHz2.5KV High Voltage Probe x1000 – Datasheet

Ultra Low Capacitance Probe

3kV peak ultra low capacitance probe

The ULCP ultra low capacitance probe is intended for voltage measurement of devices which are particularly sensitive to capacitive loading. This is particularly useful when measuring start up characteristics of low power lighting ballasts, the ULCP Ultra Low Capacitance Probe utilises a differential input design that provides a capacitance to ground of 1pF.

Voltage RatingAttenuationBandwidthSpecification Data
3kVpk, 1kVrms1000:12MHzULCP – Ultra Low Capacitance Probe – Datasheet

TT-HVP-15HF High Voltage Probe (15kVpk, 10kVrms)

15kVpk 10kVrms) voltage probe

The TTV-HVP-15HF High Voltage Probe provides 1000:1 attenuation of voltages up to 15kV, with a bandwidth of 50MHz these probes provide high voltage accurate measurement. For connection advice please contact the N4L application engineering department.

Voltage RatingAttenuationBandwidthSpecification Data
15kVpk, 10kVrms1000:150MHz15KV High Voltage Probe x1000 – Datasheet

19in Rack Mount Kits

PSM17xx Mounting Fascia Panel

frequency response analyzer rack mount kit

The PSM1700 mounting fascia panel provides a convenient, neat method of integrating the PSM1700/PSM1735 Frequency Response Analyzers into a 19in rack. The PSM itself will require mounting on a shelf (not supplied)

4UEIA Standard

PSM3750 Rack Mount Kit

power analyzer rack mount kit

The PSM3750 rack mount kit consists of two 19in rack mounting brackets providing simple integration into any EIA standard 19in rack system. The brackets are fitted to the Frequency Response Analyzer by removing the two handle fixtures situated on each side of the instrument.


ATT Series Attenuator

The ATT10, ATT20 and ATT1000 are BNC to BNC voltage attenuators designed for the PSM BNC inputs. They provide high accuracy wide bandwidth gain, typical applications are in situations when the output of a voltage attenuator (such as the TT-HV250) is above the 10Vpk range of the PSM1735 input.

ModelAttenuationBandwidthMax Input VoltageSpecification Data
ATT1010:1DC-2MHz30VpkATT10 - Datasheet
ATT2020:1DC-2MHz60VpkATT20 - Datasheet
ATT10001000:1DC-10kHz1000VrmsContact us for information