N4L PSM1735 User Manual
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N4L PSM1735 User Manual

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PSM1735
User Manual
This manual is copyright © 2006-2020 Newtons4th Ltd. and
all rights are reserved. No part may be copied or reproduced
in any form without prior written consent.
Document Title: PSM1735 User Manual v2.24
th
Document Release Date: 07
October 2020
Firmware version on release date: v1.61
Document Ref: D000175 issue 01

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Summary of Contents for N4L PSM1735

  • Page 1 This manual is copyright © 2006-2020 Newtons4th Ltd. and all rights are reserved. No part may be copied or reproduced in any form without prior written consent. Document Title: PSM1735 User Manual v2.24 Document Release Date: 07 October 2020 Firmware version on release date: v1.61...
  • Page 2 “ Do not be hasty when making measurements.” PSM1735 is a precision instrument that provides you with the tools to make a wide variety of measurements accurately, reliably, and efficiently - but good metrology practice must be observed. Take time to read this manual and familiarise yourself with the features of the instrument in order to use it most effectively.
  • Page 3 DANGER OF ELECTRIC SHOCK Only qualified personnel should install this equipment, after reading and understanding this user manual. If in doubt, consult your supplier. RISQUE D'ELECTROCUTION L'installation de cet équipement ne doit être confiée qu'à un personnel qualifié ayant lu et compris le présent manuel d'utilisation.
  • Page 4 PSM1735 user manual IMPORTANT SAFETY INSTRUCTIONS This equipment is designed to comply with BSEN 61010-1 (Safety requirements electrical equipment measurement, control, and laboratory use) – observe the following precautions:  Ensure that the supply voltage agrees with the rating of the instrument printed on the back panel before connecting the mains cord to the supply.
  • Page 5 PSM1735 user manual DECLARATION OF CONFORMITY Manufacturer: Newtons4th Ltd. Address: 1 Bede Island Road Leicester LE2 7EA We declare that the product: Description: Phase Sensitive Multimeter Model: PSM1735 Conforms to the EEC Directives: 2014/30/EU relating to electromagnetic compatibility: EN 61326-1:2013...
  • Page 6 Newtons4th Ltd. This guarantee is limited to the cost of the PSM1735 itself and does not extend to any consequential damage or losses whatsoever including, but not limited to, any loss of earnings arising from a failure of the product or software.
  • Page 7 PSM1735 user manual ABOUT THIS MANUAL The PSM1735 has a number of separate measurement functions that share common resources such as the keyboard and display. Accordingly, this manual first describes the general features and specification of the instrument as a whole;...

  • Page 8: Table Of Contents

    PSM1735 user manual CONTENTS Introduction – general principles of operation ..1-1 Voltage inputs ............1-4 Getting started ..........2-1 Unpacking .............. 2-1 Keyboard and controls ..........2-3 Basic operation ............2-4 Measurement Selectivity .......... 2-5 Using the menus ..........3-1 Selection from a list ..........
  • Page 9 PSM1735 user manual Output control ..........8-1 Generator specifications ........... 8-3 Input channels ..........9-1 Trimming x10 oscilloscope probes ......9-5 10 True RMS Voltmeter ........10-1 10.1 RMS voltmeter specification........10-4 11 Frequency response analyser ......11-1 11.1 Frequency response analyser specification ....11-5 12 Phase angle voltmeter (vector voltmeter) ...
  • Page 10 PSM1735 user manual APPENDICES Appendix A Accessories Appendix B Serial command summary Appendix C Available character set Appendix D Configurable parameters Appendix E Contact details...

  • Page 11: Introduction - General Principles Of Operation

    PSM1735 user manual Introduction – general principles of operation The PSM1735 is a self-contained test instrument, with one output and two inputs, which incorporates a suite of test functions. The PSM1735 has a wide bandwidth generator output that can be used as signal generator for sine or square waveforms.
  • Page 12 The PSM1735 is configured to perform the required test function by simple user menus, or can be controlled remotely via a serial interface (RS232), or optionally LAN interface or GPIB interface.
  • Page 13 PSM1735 user manual Generator output The output sinewave is generated by direct digital synthesis (DDS). Amplitude is set in 2 stages - a fine control and a coarse control to give excellent resolution over the whole range. The square wave is generated from the sinewave by a high speed comparator.

  • Page 14: Voltage Inputs

    PSM1735 user manual Voltage inputs Each input consists of a pair of ac, or ac+dc, coupled high impedance buffers, one for the main input and one for the secondary. The main and secondary inputs can be selected independently, to multiplex two signals to the same input, or may be used as a single differential input, main - secondary.

  • Page 15: Getting Started

    PSM1735 user manual Getting started The PSM1735 is supplied ready to use – it comes complete with an appropriate power lead and a set of test leads. It is supplied calibrated and does not require anything to be done by the user before it can be put into service.
  • Page 16 PSM1735 user manual Connect the output lead to the output BNC of the PSM1735 and two input probes to the + input BNCs of the two channels. Connect the output to both of the inputs by connecting the black clip on the output lead to the 0V clip on each of the input probes, and the red clip of the output lead to the input probes.

  • Page 17: Keyboard And Controls

    PSM1735 user manual Keyboard and controls The keyboard is divided into 5 blocks of keys: display control (5 keys top left) function keys (6 keys top right) setup keys (12 keys lower left) menu control keys (7 centre keys) action keys (4 keys lower right)

  • Page 18: Basic Operation

    DOWN to adjust the amplitude (use the OUT menu to change the size of the steps). Press START and the PSM1735 will start a frequency sweep over the specified range (set in the SWEEP menu); press TABLE to see the table of results, GRAPH to see a graph of the results and REAL TIME to return to the real time data.

  • Page 19: Measurement Selectivity

    In most applications, the signal of interest is generated by the FRA itself. When using this normal mode of operation, PSM units from N4L will automatically analyse the measurement signal with a DFT algorithm running at exactly the same frequency as the injected signal. This...
  • Page 20 PSM1735 user manual While it is not required for the user to define the selectivity, nominal values used by the PSM units are defined in the following table: speed update rate normal time slow time Measurement constant constant Selectivity fast 1/20s 0.2s...

  • Page 21: Using The Menus

    PSM1735 user manual Using the menus The PSM1735 is a very versatile instrument with many configurable parameters. These parameters are accessed from the front panel via a number of menus. Each of the main menus may be accessed directly from a specific key.
  • Page 22 PSM1735 user manual Pressing the HOME key first time reverts to the opening state where the parameters are displayed but the cursor is hidden. Pressing the HOME key at this point exits the menu sequence and reverts back to normal operation.

  • Page 23: Selection From A List

    PSM1735 user manual Selection from a list This data type is used where there are only specific options available such as the output may be ‘on’ or ‘off’, the graph drawing algorithm may use ‘dots’ or ‘lines’. When the flashing cursor is highlighting the parameter, the RIGHT key steps forward through the list and the LEFT key steps backwards through the list.

  • Page 24: Numeric Data Entry

    For example, the maximum amplitude of the PSM1735 generator is 10V peak; if a value of 15V is entered, a warning will be given and the amplitude set to the maximum of 10V.

  • Page 25: Text Entry

    PSM1735 user manual Text entry There are occasions where it is useful to enter a text string; for example, a non-volatile program may have some text as a title. Text is entered by selecting one of 6 starting characters using the main function keys on the top right hand side of...

  • Page 26: Special Functions

    PSM1735 user manual Special functions Display zoom The PSM1735 normally displays many results on the screen in a combination of small font size (no zoom) and up to 4 values in a larger font size (first zoom level). There is also an even larger font for up to 4 selected values (second zoom level).

  • Page 27: Program Store And Recall

    Program number 1 (if not empty) is loaded when the instrument is powered on so that the PSM1735 can be set to a user defined state whenever it is switched on. This is particularly useful to set system options such as phase convention, GPIB address etc.

  • Page 28: Zero Compensation

    PSM1735 user manual Zero compensation There are 3 levels of zero compensation: Trim out the dc offset in the input amplifier chain. Measure any remaining offset and compensate. Measure parasitic external values and compensate. The trim of the dc offset in the input amplifier chain is re-...

  • Page 29: Alarm Function

    PSM1735 user manual Alarm function The PSM1735 has two independent alarms that can be read remotely or can generate an audible sound. Each of the alarms can be triggered by comparison to one or two thresholds: sound the alarm if the value exceeds a threshold...
  • Page 30 PSM1735 user manual 1/3 of the measured value respectively. The repetition rate of the sounder then varies linearly as the value changes between these thresholds.

  • Page 31: Analogue Output

    PSM1735 user manual Analogue output The analogue output is a 0 to 4V dc level that represents the selected measurement. To program the analogue output, first select the functions for the zoom; up to four measurements can be selected for the display, the alarm is applied to any one of them;...

  • Page 32: Data Hold

    PSM1735 user manual Data hold When in real time display mode, the data on the display can be held at any time by pressing the REAL TIME key. When HOLD is activated a warning message is briefly displayed and the word HOLD appears in the top right hand corner of the display.

  • Page 33: Parallel Port

    PSM1735 user manual Parallel port The PSM1735 has a logic level parallel port with 8 output lines and 4 input lines, which can be used to interface with other parts of a test system or with a PLC. The parallel port can be used either as a general purpose...

  • Page 34: Sweep Results Store And Recall

    PSM1735 user manual Sweep results store and recall There are 30 non-volatile storage locations that can store the results of frequency sweeps. Each location can store the sweep results for up to 50 points; larger sweeps can be stored in multiple locations:...

  • Page 35: Using Remote Control

    EOI with EOI All the functions of the PSM1735 can be programmed via either interface, and results read back. When the IEEE488 interface is set to ‘remote’ the RS232 port is ignored. The commands are not case sensitive and white space characters are ignored (e.g.
  • Page 36 *ESR? (see section 5.1). The PSM1735 also maintains a status byte consistent with the requirements of the IEEE488.2 protocol, that can be read either with the IEEE488 serial poll function or by the mandatory command *STB? over RS232 or IEEE or LAN (see section 5.2).

  • Page 37: Standard Event Status Register

    PSM1735 user manual Standard event status register bit 0 OPC (operation complete) cleared by most commands set when data available or sweep complete bit 2 QYE (unterminated query error) set if no message ready when data read bit 3 DDE...

  • Page 38: Serial Poll Status Byte

    PSM1735 user manual Serial Poll status byte bit 0 RDV (result data available) set when results are available to be read as enabled by DAVER bit 1 SDV (sweep data available) set when sweep results are available to be read as enabled by DAVER...

  • Page 39: Rs232 Connections

    4. To connect the PSM1735 to a PC, use a 9 pin female to 9 pin female null modem cable: 1 & 6 1 & 6...

  • Page 40: Data Streaming

    The window is adjusted to synchronise to the measured frequency. The PSM1735 buffers the data and transmits at the fastest rate that is possible. The buffer depth is over 8000 data values so more than 5 seconds of data can be captured at the fastest rate of 1500 readings per second even if the data is not read at all.

  • Page 41: System Options

    PSM1735 user manual System options Press SYSTEM to access the system options. Measurements of phase can be expressed in one of three conventional formats: -180 to +180 (commonly used in circuit analysis) 0 to -360 (commonly used in power applications) 0...
  • Page 42 PSM1735 user manual displayed showing the new value. This message can be disabled. The 6 main function keys, FRA, PAV, LCR, RMS, POWER, HARM, can be used to load stored configurations as a “one-touch” way of configuring the instrument for specific applications.

  • Page 43: User Data

    PSM1735 user manual User data The PSM1735 can be personalised by entering up to 3 lines of user data as text (see section on text entry). User data is displayed every time that the instrument is switched on to identify the instrument. The entered text may also be read over the communications to identify the instrument (see USER?).

  • Page 44: Measurement Options

    PSM1735 user manual Measurement options ACQU - Acquisition options In normal acquisition mode, the window over which the measurements are computed is adjusted to give an integral number of cycles of the input waveform. The results from each window are passed through a digital filter equivalent to a first order RC low pass filter.
  • Page 45 PSM1735 user manual There is also an option to set a specific size of the window to a value other than the preset options. In order to synchronise to an integral number of cycles, the window size is either reduced by up to 25% or increased as necessary.
  • Page 46 PSM1735 user manual Single measurement mode makes individual measurements in response to a trigger – manually via the keypad or *TRG over the communications. After the measurement, the output can be specified to be switched off, left on, or left on with dc only. By setting the...

  • Page 47: Datalog

    PSM1735 stores the next available measurement after the datalog interval has elapsed: the actual elapsed time is attached to each datalog record, is displayed with the data on the table or each graph, and returned with each record over the communications (RS232, LAN or GPIB).
  • Page 48 PSM1735 user manual The datalog options are set up with the ACQU menu. The datalog is started with the START key and stopped with the STOP key unless the store becomes full first. The zero reference for the elapsed time is taken as the first data measurement after START.

  • Page 49: Sweep - Frequency Sweep Options

    PSM1735 user manual SWEEP - Frequency sweep options All ac measurements using the PSM1735 generator can be swept across a frequency range. The start frequency, stop frequency and number of steps up to 2000 can be specified. The measurements are subjected to the same speed constraints set in the ACQU menu, but the filtering does not apply on each measurement point.
  • Page 50 PSM1735 user manual Each frequency point is an entirely new measurement and autoranging is restarted (if enabled). For the fastest possible sweeps, select manual ranging. As each frequency point is a new measurement, filtering has no effect on a single sweep, but fixed time filtering can be applied independently on each frequency point if repeat sweep in selected.

  • Page 51: Trim - Trim Function

    PSM1735 user manual TRIM - Trim function The trim function on the PSM1735 is a powerful and versatile feature that allows closed loop control of the generator amplitude. It allows a specific measurement to be programmed for either CH1 and CH2 and the generator output will be adjusted to maintain the measured voltage or current.
  • Page 52 PSM1735 user manual Output control The output for the signal generator is digitally synthesised at an update rate of 150Msamples/s. With the output filtering, this gives a good sinewave waveform, even at 35MHz, while preserving very accurate frequency control. The output amplitude is controlled in 2 stages – a fine control with 11 bit resolution, and a coarse control with 8 binary weighted steps.
  • Page 53 PSM1735 user manual An offset may be added to any output to bias the signal or to null out any dc present with a resolution of +/-5mV. The LEFT and RIGHT keys adjust the frequency of the generator by a fixed increment stored via the STEP menu;...

  • Page 54: Output Control

    PSM1735 user manual Generator specifications General Nominal Accuracy frequency 0.05% * amplitude 10% < 10MHz, 20% < 35MHz) Nominal Accuracy amplitude 1% < 10MHz, 5% < (with trim) 35MHz) output impedance 50 2% output voltage 10V peak (Open Circuit) * offset 10V peak maximum...

  • Page 55: Input Channels

    PSM1735 user manual Input channels The two input channels each have two separate, ground referenced inputs that can be used independently or together as a differential input. The two channels are controlled independently but sampled synchronously. Each input channel may be selected to use:...
  • Page 56 PSM1735 user manual The input ranges have nominal full scale values set with a ratio of 1:10 from 1mV to 10V. When the PSM1735 is using selective high frequency measurements (heterodyning) the ranges extend by approximately 50%. This gives the following ranges:...
  • Page 57 PSM1735 user manual The input ranges may be selected manually, or by auto ranging (default). The start range for auto ranging may be selected if it is known that the signal will not be below a certain level. There is also an option to auto range ‘up only’ so that a test may be carried out to find the highest range.
  • Page 58 PSM1735 user manual For measuring signals that are biased on a dc level (such as an amplifier operating on a single supply or the output of a dc PSU), ac coupling can be used. AC+DC coupling is the normal option and should be used where possible.

  • Page 59: Trimming X10 Oscilloscope Probes

    Trimming x10 oscilloscope probes To minimise the loading effects at high frequencies, x10 oscilloscope probes can be used with the PSM1735. For optimum performance, the probes need to be trimmed to match the input capacitance of the instrument and the probes need to be corrected for gain errors.
  • Page 60 PSM1735 user manual Repeat the procedure for the probes connected to the secondary inputs by selecting secondary voltage inputs in the CH1 and CH2 menu. To adjust for the tolerance within the probes (typically 1%), the main inputs can be scaled and the secondary inputs can be adjusted.

  • Page 61: 10 True Rms Voltmeter

    These are fundamental definitions that are valid for all waveshapes. For a pure sinewave, the formulae equate to peak/2, but this cannot be applied to other waveshapes. The PSM1735 computes the true rms value from the fundamental definition for sampled data. 10-1...
  • Page 62 PSM1735 user manual The dc present is given by: 2  dc = 1/2 v() d For a sampled signal, the formula becomes: i = n-1  dc = 1/n v[i] i = 0 where n is the number of samples for an integral number of complete cycles of the input waveform.
  • Page 63 PSM1735 user manual important that the PSM1735 does not auto range while measuring surge – either set the range to manual or repeat the test with ranging set to up only. To reset the maximum, press START. Crest factor is derived from the peak and rms:...

  • Page 64: Rms Voltmeter Specification

    PSM1735 user manual 10.1 RMS voltmeter specification channels 2 differential display 5 digits measurement true rms, ac, dc, dBm, peak, cf, surge coupling ac or ac+dc frequency dc to 1MHz (heterodyning not available) 20Hz to 1MHz (ac only coupling) max input 10V peak...

  • Page 65: 11 Frequency Response Analyser

    PSM1735 user manual 11 Frequency response analyser The PSM1735 measures the gain and phase of channel 2 relative to channel 1 using a discrete Fourier transform (DFT) algorithm at the fundamental frequency. The DFT technique can measure phase as well as magnitude and is inherently good at rejecting noise –...
  • Page 66 PSM1735 user manual For a sampled signal, the formulae become: i = n-1  = 1/n v[i].cos(2ci/n) i = 0 i = n-1  = 1/n v[i].sin(2ci/n) i = 0 where n is the number of samples for an integral number of complete cycles of the input waveform, and c is the number of cycles.
  • Page 67 The PSM1735 can operate either in real time mode at a single frequency where the gain and phase are filtered and updated on the display, or it can sweep a range of frequencies and present the results as a table or graphs of gain and phase.
  • Page 68 Although it is most usual to use the PSM1735 generator when performing gain/phase analysis, there may be circumstances where this is impractical, for example measuring across a transformer under load. In this case,...

  • Page 69: Frequency Response Analyser Specification

    PSM1735 user manual 11.1 Frequency response analyser specification Frequency response (gain/phase) analyser frequency 10uHz to 35MHz (own generator) 20mHz to 500kHz (external source) max input 10V peak input ranges 10V, 3V, 1V, 300mV, 100mV, 30mV, 10mV, 3mV, 1mV ranging full auto, up only, or manual input impedance 1M // 30pF (exc.

  • Page 70: Phase Angle Voltmeter (Vector Voltmeter)

    The results may be expressed as magnitude and phase, or as separate in-phase and quadrature components. The PSM1735 measures the in-phase and quadrature components at the fundamental frequency using DFT analysis as described in the section on frequency response analysis.
  • Page 71 There is a phase offset option that applies a vector rotation of a user selectable phase shift to the CH2 input data. The PSM1735 can operate either in real time mode at a single frequency where the measurements are filtered and updated on the display, or it can sweep a range of frequencies and present the results as a table or graphs.
  • Page 72 It has no function following a sweep. Although it is most usual to use the PSM1735 generator when making Phase Angle Voltmeter measurements, there may be circumstances where this is impractical, for example measuring LVDT displacement under actual circuit conditions.

  • Page 73: Phase Angle Voltmeter Specification

    PSM1735 user manual 12.1 Phase angle voltmeter specification Phase angle voltmeter (vector voltmeter) frequency 10uHz to 35MHz (own generator) 20mHz to 500kHz (external source) measurement type DFT analysis, and true rms measurements magnitude, phase, in-phase & quadrature components, tanΦ, in-...

  • Page 74: 13 Power Meter

    PSM1735 user manual 13 Power meter power meter measures total power fundamental power of the signal present at the input terminals to the bandwidth of the instrument (>1MHz). Above 1MHz, only the fundamentals are measured. One of the inputs must be configured as an external shunt input.
  • Page 75 These are elementary definitions that are valid for all waveshapes. The PSM1735 computes the true watts value from the elementary definition for sampled data. Formulae for the components at the fundamental frequency are given in the section on frequency response analysis;...
  • Page 76 PSUs. Use “autorange up” to find the range. The PSM1735 blanks the results when either of the measured rms signals are low compared to the full scale range. This function can be disabled if desired in the SYSTEM menu.

  • Page 77: Power Meter Specification

    PSM1735 user manual 13.1 Power meter specification Power meter current input external shunt display 5 digits measurement W, VA, PF, fundamental, rms, phase coupling ac or ac+dc frequency dc to 1MHz 1MHz to 35MHz (fundamentals only) 20Hz to 35MHz (AC only coupling) max input 10V peak...

  • Page 78: 14 Lcr Meter

    The easiest way to use the LCR meter is with the ‘LCR active head’ (see accessories) that fits onto the front of the PSM1735 and provides 4 wire Kelvin clip connections to the component under test. The active head provides a...
  • Page 79 PSM1735 user manual For “shunt” connection, shown above, the current is measured directly across the shunt using CH2 while the voltage across the Zx is measured by CH1. Notice that the positive inputs to both CH1 and CH2 are connected to the midpoint to minimise common mode loading effects.
  • Page 80 The frequency may be taken from its own generator or from the circuitry under test. From the fundamental components of voltage, (a + jb), and those of the current, (c + jd), the PSM1735 computes the complex impedance given by: = v / i...
  • Page 81 CH1 menu in order to reliably measure the small ac voltage present. The PSM1735 can operate either in real time mode at a single frequency where the measurements are filtered and updated on the display; or it can sweep a range of frequencies and present the results as a table or graphs.
  • Page 82 It has no function following a sweep. Although it is most usual to use the PSM1735 generator when performing LCR measurements, there may be circumstances where this is impractical, for example measuring the inductance of a transformer primary winding under load.

  • Page 83: Applying Compensation

    Connect a known reference component to the system, enter the known phase shift of the component as the “phase reference” in the ZERO menu and select “phase adjust”. The PSM1735 then applies a compensating vector rotation subsequent measurements.
  • Page 84 PSM1735 user manual Here, the ZERO key has been pressed on the PSM front panel to present the LCR Compensation screen and then by using the navigation keys, the frequency option has been changed form ‘single’ to ‘sweep’. Here it can be seen that ‘sweep start’, ‘sweep end’ and ‘step’...
  • Page 85 PSM1735 user manual Saved Compensation Single When using single frequency compensation, there is no store function since the compensation of a single frequency is fast. The Compensation will be lost when the instrument is switched off. However, when the instrument settings are saved to a program file in the internal flash memory of the PSM17xx (refer to section 4.2), any single point compensation that...
  • Page 86 PSM1735 user manual be used when both processes have been completed. A new sweep compensation can be made at any time without affecting the stored compensation but only one sweep store is provided, therefore pressing ‘store’ after a new compensation has been made will overwrite the previous compensation.

  • Page 87: Lcr Meter Specification

    PSM1735 user manual 14.2 LCR meter specification LCR meter frequency 10uHz to 35MHz (own generator) measurement type DFT analysis measurements L, C, R (ac), Q, tan, impedance, phase, admittance series or parallel circuit conditions auto, or manual display numeric values...

  • Page 88: 15 Harmonic Analyser

    PSM1735 user manual 15 Harmonic analyser The PSM1735 harmonic analyser computes multiple DFTs on the input waveforms in real time (refer to the chapter on frequency response analysis for the formulae for DFT analysis). There are three modes of operation: single harmonic, difference thd, and series thd.
  • Page 89 HARM menu. The PSM1735 can operate either in real time mode at a single frequency where the measurements are filtered and updated on the display; or it can sweep a range of frequencies and present the results as a table or graphs.
  • Page 90 PSM1735 user manual Although it is most usual to use the PSM1735 generator when making harmonic measurements, there may be circumstances where this is impractical, for example measuring harmonic currents drawn from the mains. In this case, turn off the PSM1735 generator (OUT menu) and the frequency reference for the analysis is measured from channel 1.

  • Page 91: Harmonic Analyser Specification

    PSM1735 user manual 15.1 Harmonic analyser specification Harmonic analyser fundamental 10uHz to 500kHz (own generator) frequency 20mHz to 500kHz (external source) harmonic 10uHz to 1MHz frequency measurement type multiple DFT analysis measurements single harmonic, differential thd, thd by series of harmonics...

  • Page 92: 16 Transformer Analyser

    (see accessories) that connects to the PSM1735 BNC connectors via the BNC splitters and also to the PSM1735 extension port. Using the fixture, with appropriate source and load resistors, the test configuration and winding selection is selectable from the front panel. Active buffers within the fixture minimise the effects of stray capacitance and inductance.
  • Page 93 The PSM1735 can operate either in real time mode at a single frequency where the measurements are filtered and updated on the display; or it can sweep a range of frequencies and present the results as a table or graphs.
  • Page 94 A nominal number of turns may be entered using the SETUP menu if known and the PSM1735 will then also display the computed number of turns. As the inputs are independent of the output it is possible to energise a third winding when measuring turns ratio, or only two windings may be used.

  • Page 95: Inductance & Leakage Inductance

    PSM1735 output across the series combination of the source resistance and winding. Connect the CH1 input across the winding to measure the voltage, and CH2 across the series resistance (note that the polarity of external shunt input is the opposite of that for voltage).

  • Page 96: Ac Resistance And Q Factor

    PSM1735 user manual 16.3 AC resistance and Q factor AC resistance is measured the same way as inductance with CH1 monitoring the voltage across the winding, and CH2 monitoring the current through it via the external shunt (source resistance). The Q factor measurement is an effective way of detecting a shorted turn –...

  • Page 97: Interwinding Capacitance

    PSM1735 output across the transformer from the series resistance to another winding. Connect the CH1 input across the transformer from one winding to the other to...

  • Page 98: Magnetising Current

    PSM1735 user manual 16.6 Magnetising current The magnetising current is the current drawn by the primary, energised under normal operating conditions but without any secondary load. It is typically measured on power transformers rather than signal transformers so although the transformer analyser fixture, TAF01, will...

  • Page 99: Return Loss

    PSM1735 user manual 16.7 Return loss Return loss is a measure of impedance mismatch in signal transformers that are terminated with the design load resistance. The secondary winding is terminated with the appropriate load resistance and the primary is energised via a source...

  • Page 100: Insertion Loss

    As a figure of merit, a lower value of insertion loss indicates a better transformer. To manually connect a transformer for insertion loss measurement, fit the appropriate source resistance in series with the primary winding then connect the PSM1735 16-9...
  • Page 101 PSM1735 user manual output and CH1 differential input across the series combination of the source resistance and the primary winding. Connect the appropriate load resistance and CH2 differential input across the secondary. When using transformer analyser fixture, connections for insertion loss are made automatically by relays.

  • Page 102: Harmonics And Distortion

    The primary of the transformer is energised either by the output of the PSM1735 or by external means and CH2 is connected across the secondary. It is usual to measure harmonic distortion with the secondary loaded.

  • Page 103: Longitudinal Balance

    PSM1735 user manual 16.10 Longitudinal balance Longitudinal balance is a measure of the common mode rejection ratio, CMRR, of the transformer. Longitudinal balance requires external circuitry to give the required accuracy – a plug in module is available for the...
  • Page 104 PSM1735 user manual Transformer analyser specification Transformer analyser frequency 10uHz to 35MHz (own generator) 20mHz to 500kHz (external source) measurement type DFT analysis, true rms as appropriate measurements turns ratio turns inductance leakage inductance ac resistance dc resistance interwinding capacitance...
  • Page 105 PSM1735 user manual Appendix A – Accessories ACCESSORIES...
  • Page 106 PSM1735 user manual Power meter adaptors The power meter adaptors allow easy and safe connection of the PSM1735 to a mains appliance under test to measure the power or harmonics. The appliance under test plugs into an IEC mains outlet on...
  • Page 107 PSM1735 user manual 75 / 600 output adapter The generator output from the PSM1735 has a series impedance of 50. The output adapter fits directly onto the front of the instrument and provides 2 outputs: 75 via a BNC connector 600...
  • Page 108 BNC connections for use with Kelvin leads to connect to the component under test. A cable from the active head connects to the AUX port on the front of the PSM1735 to allow selection of one of the three internal shunts: shunt...
  • Page 109 It connects to the BNC connectors on the front of the PSM1735 and is controlled by the PSM1735 via the extension port. It supports transformers with 2 single windings, or with 1 single winding and one split winding.
  • Page 110 When testing the stability of control loops it is necessary to inject a small disturbance signal into the loop. The PSM1735 output is ground referenced so it is necessary to isolate the output before it can be connected to the loop.
  • Page 111 PSM1735 may be displayed in normal scientific notation with an identifying label. Strings to be sent to the PSM1735 can be stored in a “script file” and executed automatically. The script file is created with any text editor and includes three types of lines (interpreted by the first character on each line): lines beginning with "...
  • Page 112 PSM1735 user manual Appendix B – Serial command summary command format reply format *CLS *ESE,value *ESE? single integer data value *ESR? single integer data value *IDN? company,product,serial no,version *OPC? 0 or 1 *RST *SRE,value single integer data value *SRE? *STB?
  • Page 113 PSM1735 user manual FILTER,type,dynamics FRA? freq,mag1,mag2,dB,phase FRA,SWEEP? n lines of GAINPH? data FREQUE,frequency FSWEEP,steps,start,end GAINPH GAINPH? freq,mag1,mag2,dB,phase GAINPH,SWEEP? n lines of GAINPH? data HARMON,scan,para,h,hmax HARMON? freq,mag1,mag2,hmag1,hmag2,h1,h2 freq,mag1,mag2,thd1,thd2,h1,h2 HARMON,SWEEP? n lines of HARMON? data HARMON,SERIES? mag1,%1,1,mag2,%2,2 1 line for each harmonic...
  • Page 114 PSM1735 user manual POWER,integration type POWER,WATTS? W,W.f,VA,VA.f,pf,pf.f,Wdc,W.h,freq POWER,RMS? rms1,rms2,dc1,dc2,fnd1,fnd2,1,2 POWER,INTEGR? Wh,Wh.f,VAh,VAh.f,pf,pf.f,Ah,Ah.f,t PPORT,value PPORT? single integer data value PROGRAM,function,number PROGRAM? CR terminated text string RANGE,ch,ranging,range RESOLU.format REZERO RUN? data SCALE,channel,factor SCALE,channel? single real data value SHUNT,channel,resistance SHUNT,channel? single real data value...
  • Page 115 PSM1735 user manual ZERO ZERO,DELETE ZOOM,level,d1,d2,d3,d4 ZOOM? level,d1,d2,d3,d4...
  • Page 116 PSM1735 user manual Appendix C – Available character set The following characters can be selected in text entry mode. The table is to be read across then down (eg, starting at space and repeatedly pressing NEXT gives ! “ # $ % & ‘ ( ) * etc.)
  • Page 117 PSM1735 user manual Appendix D – Configurable parameters All parameters can be accessed using the CONFIG command: CONFIG,parameter? CONFIG,parameter,data Number Function System parameters operating mode bandwidth auto or wide autozero manual or auto blanking disable phase convention main output on/off...
  • Page 118 PSM1735 user manual coupling channel 2 scale factor channel 1 scale factor channel 2 external shunt channel 1 external shunt channel 2 input connection channel 1 input connection channel 2 General parameters 5/6 digit resolution phase reference Display parameters zoom level...
  • Page 119 PSM1735 user manual Power meter parameters integration type Streaming parameters data streaming data streaming window size Harmonic analyser parameters mode selected harmonic maximum harmonic computation Bargraph scale LCR sweep zero parameters sweep compensation compensation start frequency compensation stop frequency compensation steps...
  • Page 120 PSM1735 user manual LCR meter parameters computation series/parallel sweep graph option active head control impedance lin/log phase adjust value reference impedance reference type connection gain/phase analyser parameters phase or delay time selection dB offset gain/phase margin enable ratio selection System parameters...
  • Page 121 PSM1735 user manual alarm 2 high threshold alarm 2 low threshold Graph functions graph 2 manual/auto graph 2 maximum graph 2 minimum Phase angle voltmeter parameters computation LVDT scaling manual null meter ranging null maximum phase offset Trim parameters ac trim enable...
  • Page 122 PSM1735 user manual Appendix E – Contact details Please direct all queries or comments regarding the PSM1735 instrument or manual to: Newtons4th Ltd. 1 Bede Island Road Leicester LE2 7EA United Kingdom Tel: (0116) 230 1066 international +44 116 230 1066...
  • Page 123 PSM1735 comments serial main release: date: number: dsp release: fpga release: boot release: (press SYS then LEFT) your contact details: comments: detailed description of application or circumstances: Please post or fax to Newtons4th Ltd.

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