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Review – Agilent Infiniivision MSO-X 3024A Mixed Signal Oscilloscope

Hello Readers

In this article we examine the Agilent Technologies Infiniivision MSO-X 3024A Mixed Signal Oscilloscope. Please note that the review unit has the latest version 2.0 firmware (existing owners can upgrade with the free download).

Initial Impressions

Unlike smaller instruments the packaging is plain and non-descript, however the MSO is protected very well for global shipping and arrived in perfect condition. Inclusions will vary depending on the particular model, however all come with a calibration certificate, user guide on CD and a power lead.

image1

Four passive 300MHz probes are included with the MSO-X3024A:

image1a

Due to the constant upgrading of the firmware the lack of a printed user manual is no surprise. You can download the manual as well as the service, programming and  educational lab guides from the documents section of the product web page – which make good reading to get a feel for the unit.

Now for a tour around the unit. Coming from a smaller DSO or an analogue model, the first thing that strikes you is the display. 8.5” diagonal with 800×480 resolution:

image2

Unlike cheaper brands the larger screen is not extrapolating data from a smaller image – each pixel is separately used. The front panel is clean and uncluttered. Each button and knob feels solid and responsive, and if pressed and held down, a small help window appears with information about the item pressed. Note that each analogue channel has independent controls for vertical position and V/div sensitivity (the minimum sensitivity is 1mV/division). This saves a lot of time and possible confusion when working on time-sensitive applications.

Around the back we find the cooling van ventilation on the left, the IEC AC power socket on the bottom-right, manufacturing data and so on. The fan is just audible, however the noise from a desktop computer drowns it out. On the far right near the top are separate USB connections for device and host mode, and the external trigger input and output sockets. Apart from the trigger out signal the socket can also be set to give a 5V pulse on a mask test failure or the optional WaveGen sync pulse.

image3

Below this is a space for a Kensington lock cable, and the optional modules – the VGA/LAN adaptor or the GPIB bus module. On the right is my old faithful GW 20 MHz analogue CRO. Finally, there is a compartment on the top of the unit that can hold two probes comfortably, and four at a pinch:

image4

As the unit is can be considered a small computer, it takes time to boot up – just over thirty seconds. (The operating system is Windows CE version 6.0). The user-interface is quite simple considering the capability of the unit. The six soft-keys below the display are used well, and also can call a separate list of options under each button.

When such a list is presented, you can also use the “Push to select” knob on the right hand side of the display to select an option and lock in by pressing the knob in. Below the soft keys from left to right are: BNC output for the optional function generator, digital inputs for logic analyser, USB socket for saving data to a USB drive, probe points for calibration and demonstration use, and four probe sockets. Connections exist that can interface with optional Agilent active probes.

Specifications

This instrument falls within the range of Agilent’s new Infiniivision 3000-series oscilloscopes. The range begins with the DSO-X3012A with 100MHz bandwidth and two channels, through to the DSO-X3054A with 500 MHz bandwidth and four channels. Furthermore the range is extended with the MSO-X models that include a sixteen channel logic analyser.

Some of you will know there is also the Infiniivision 2000-series, and wonder why one would acquire a 3000-series. There are three excellent reasons for doing so:

  1. Waveform update rate is 50000 per second on a 2000, one million per second on a 3000;
  2. Memory depth on a 2000 is 100 kilopoints; 3000s have 2Mpts standard or 4Mpts optional;
  3. Eight vs. sixteen digital channels when specified as an MSO-X model.

For a full breakdown of specifications please download the Agilent data sheet located here.

Getting Started and general use

The process from cutting open the packaging to measuring a signal is quite simple – just plug it in, connect probes and go – however some probe compensation is required, which is explained quite well in the manual. There are strong tilting bales under the front side which can be used to face the unit upwards. At this point the unit is ready to go – you can start measuring by using the Auto Scale function and let the MSO-X3024A determine the appropriate display settings.

However there is no fun in that – the vertical scale can be manually adjusted between 1 mV and 50V per division, the horizontal between 2 nanoseconds and 50 seconds per division. These values can be selected rapidly or (by pressing the knob in) in a fine method for more precise values. If working with more than one channel, each can be labelled using a pre-set description or select a label from a list. One can also alter the display between X-Y, horizontal and roll modes.

Each channel has separate controls for coupling – DC/AC but no GND, as the earth point is shown on the LCD. Impedance can be 1M or 50 ohm. One can also limit bandwidth to 20MHz to remove high-frequency interference.

Capturing data is very easy, you can save images as .png or .bmp files in grey scale or colour , data in .csv form and so on. You can also assign popular functions to a “Quick Action” button – one press and it is done. For example I use this as a “save bitmap” button to send the screen image to the USB drive. If the optional LAN/VGA module is installed screens can be captured by the host computer via the network. Finally there is a very basic file explorer available to find files on the USB drive as well.

Waveforms can also be stored and used later on as references for other measurements. When reviewed they appear as an orange trace – for example R1:

rrr

The horizontal zoom mode activated using keys to the right of the horizontal control is very useful. Agilent call this “Mega Zoom” and it certainly works. Consider the following screen shot – the 32.768kHz square-wave from a Maxim DS1307 real-time clock is being analysed:

megazoom

The time base is 10uS per division – and using the zoom we can get down to two nanoseconds per division and investigate the ringing on fall of the square-wave. This is great for investigating complex signals over short periods. Awesome.

Capturing infrequent events is made simple by the combination of the one million waveforms per second sampling rate, and the use of infinite display persistence. In the following example a clock with very infrequent glitch is being sampled. By setting persistence to infinite, as soon as the infrequent glitch occurs it can be displayed and held on the screen. For example:

infreq

Triggering

There is a plethora of triggering options available. Standard modes include: edge, edge then edge, pulse-width (customisable), pattern trigger (for logic analyser – you can create your own patter of high, low, or doesn’t matter with comparison operators for duration), hex bus trigger, OR trigger, customisable rise/fall time trigger, nth edge burst trigger which allows  you to nth edge of a burst after an idle time, runt trigger on positive or negative pulse, setup and hold trigger, on video signals (PAL, PAL-M, NTSC, SECAM), and USB packets. Phew. Furthermore, if you have any of the optional decoding and analysis licenses, they include triggering on the matching signal type (see later).

Math modes

Performing math waveforms on analogue channels is done via a seperate Math button, and the operations available are addition, subtraction, multiplication, differentiation, integration, square root and FFT.

Waveform statistics

When the time comes to further analyse your measurement data, there area variety of measurements that can be taken, and they can be displayed individually, such as in the following:

stats1

or all in a summary screen:

allstats

Or you can manually use the cursors to determine information about any part of a wave form, for example:

cursors

Logic Analyser

Everything required is included with the MSO-X3024A for the sixteen channel logic analyser, including a very long dual-head probe cable:

lacables

as well as sixteen grabbers and some extension runs:

lacables2

Setup and use was surprisingly simple, just connect the probe cable head to ground, insert grabbers onto the ends of each channel wire, and connect to the signal pins to analyse. You can have all sixteen channels and the four analogue channels active at once, however when doing so the screen is quite busy. You can adjust the height  for each digital channel. Here we are measuring two analogue and eight digital channels:

msoinaction

As always there are many forms of customisation. Automatic scaling is available the same as analogue measurement. You can set the threshold levels for high and low, and presets exist for TTL, CMOS, ECL and your own custom levels. The cable is very well-built (made in the USA) and the socket on the MSO is a standard, very solid IDC connector. Thanks to the use of the IDC connector you could also make your own probes or extension cable for the analyser. Digital channels can also be combined and displayed as a data bus, with the data values shown in hexadecimal or binary – for example:

hexbus

binbus

Options

Both the 2000- and 3000-series Infiniivision units have a variety of options and upgrades available either at the time of purchase or later on. Agilent have been clever and installed all the software-based options in the unit – when required they are “unlocked” by entering a licence key given after purchase. Trial 14-day licenses are generally available if you want to test an option before purchase. You can also upgrade the bandwidth after purchase – for example if you started with a 100MHz a licence key purchase will upgrade you to 200MHz , or 350 to 500MHz. However if you wish to upgrade a 200MHz to 350/500, this needs to be performed at at Agilent service facility. Surprisingly the logic analyser upgrade that converts a DSO-X to an MSO-X is user-installable. For more information on the upgrade options and procedures please visit here.

Memory Upgrade (DSOX3MEMUP)

A simple yet useful option – it doubles the total memory depth to 4 Mpts interleaved.

LAN/VGA Module (DSOXLAN)

This options really opens up the MSO to the world (and is a lot of fun..) – it is inserted into the port at the rear of the unit:

lanvga1

VGA output is very simple – no setup required. Just plug in your monitor or projector and you’re ready to go -for example, with a 22″ LCD monitor:

monitorview

The educational benefits of the LAN/VGA module are immediately apparent – instead of having twenty classmates huddle around one MSO while the instructor demonstrates the unit, the display can be show on the classroom projector or a large monitor. The MSO display is still fully active while VGA output is used.

LAN connection via Ethernet was also very simple. The MSO can automatically connect to the network if you have a router with DHCP server. Otherwise you can use the Utility>I/O>LAN Settings function to enter various TCP/IP settings and view the MSO’s MAC address.

Once connected you can have complete control of the MSO over your network. Apart from saving screen shots:

remotesaveimage

There is a “simple” remote control interface that contains all the controls in a standard menu-driven environment:

simpleremotepanel

Or you can have a realistic reproduction of the entire MSO on your screen:

fullremotepanel

The full remote panel is completely identical – it’s “just like being there”. The ability to monitor your MSO from other areas could be very useful. For example using the mask testing in a QC area and watching the results in an office; or an educator monitoring students’ use of the MSO.

Furthermore you can view various data about the MSO, such as calibration date and temperature drift since calibration, installed options, serial number, etc. remotely via the web interface.

GPIB Module (DSOXGPIB)

This allows you to connect your MSO to an IEEE-488 communications bus for connection to less contemporary equipment.

Segmented Memory Option (DSOX3SGM)

This options allows you to capture infrequent multiple events over time. For example, you want to locate some 15 mS pulses that occur a few times over the space of an hour. All you need to do is set the triggering to pulse-width, specify the minimum/maximum pulse width to trigger from, then hit Acquire>Segmented, the number of segments to use and you’re off. When the pulses have been captured, you can return and analyse each one as normal. The unit records the start time and elapsed time for each segment, and you can still use zoom, etc., to examine the pulse. For example:

segment

Embedded Serial Triggering and Analysis (DSOX3EMBD)

Debugging I2C and SPI buses are no longer a chore with this option. For example with I2C just probe you SDA and SCK lines, adjust the thresholds in the menu option and you’re set. Apart from displaying the bytes of data below the actual waveform, there is a “Lister” which allows you to scroll back and forth along the captured data along with correlating times. In the following example a Maxim DS1307 RTC IC has been polled:

i2c_lister

The Lister details all – in the example we sent a zero to address 0x68, which caused the DS1307 to return the seven bytes of time and date data. This is an extremely useful option and is very useful when working with a range of sensors and other parts that use the I2C bus. The SPI bus analysis operates in exactly the same manner. Adding this option also allows triggering on I2C data as well.

FlexRay Triggering and Analysis (DSOX3FLEX)

The optional FlexRay measurement applications offer integrated FlexRay serial bus triggering, hardware-based decoding and analysis. The FlexRay measurement tools help you more efficiently debug and characterize your FlexRay physical layer network by having the ability to trigger on and time-correlate FlexRay communication with your physical layer signals. So if you are working on the ECU of your Rolls-Royce or new BMW 7-series, you can use an MSO that matches the quality of the vehicle under examination. Here is an example of the FlexRay being monitored in the lister:

flexray

RS232/UART Serial Decode and Trigger (COMP/MSOX3000-232)

This option allows RS232, 422, 485 and UART decoding and triggering, as well as the use of the Lister to analyse the data. For example:

uartdecode

Advanced Math (DSOX3ADVMATH)

This option adds more math functions to enhance your waveform analysis, including: divide, base-10 logarithm, natural logarithm and exponential.

CAN/LIN Triggering and Serial Decode (DSOX3AUTO)

Again, allows decoding of automotive CAN and LIN bus signals, and the use of the Lister. For example:

can_decode

lin_decode

Military Standard 1553 and ARINC429 Standards Serial Triggering and Decoding (DSOX3AERO)

The option exists for decoding and triggering of the above bus types. According to Agilent the Mil-STD 1553 serial bus is primarily used to interconnect avionics equipment in military aircraft and spacecraft(!). This bus is based on tri-level signaling (high, low, & idle) and requires dual-threshold triggering, which the 3000X supports. This bus is also implemented as a redundant multi-lane bus (dual-bus analysis), which is also supported by the 3000X.

The ARINC 429 serial bus is used to interconnect avionics equipment in civilian aircraft (Boeing & Airbus). This bus is also based on tri-level signaling (high, low, & null) and requires dual-threshold triggering, which the 3000X supports. Since ARINC 429 is a point-to-point bus, multi-lane analysis is also required to capture both send and receive data. So if you need this capability – Agilent has you covered.

milbus

Video Triggering and Analysis Application (DSOX3VID)

The DSOX3VIDEO option provides triggering on an array of HDTV standards, including:

  • 480p/60, 567p/50, 720p/50, 720p/60
  • 1080i/50, 1080i/60
  • 1080p/24, 1080p/25, 1080p/30, 1080p/50, 1080p/60
  • Generic (custom bi-level and tri-level sync video standards)

The 3000X Series oscilloscope already comes standard with NTSC, PAL, PAL-M, and SECAM support. Example of video analysis:

dsox3vid

Audio Serial Triggering and Analysis (DSOX3AUDIO)

And not surprisingly this is an option to allow decoding of and triggering from I2S digital audio data. For example:

i2s_decode

Mask Limit Testing (DSOX3MASK)

This is another interesting and useful option, idea for quality testing, benchmarking and so on. First you create a mask by measuring the ideal waveform, and then feed in the signal to be compared with the ideal mask. Mask limit testing can operate at up to 280000 comparisons per second. You can view pass/fail statistics, minimum sigma and so on, for example – a perfect test:

mask1

… then a change of frequency for a few cycles:

mask2

Furthermore you can specify the number of tests, change source channel, specify action upon errors, etc. Finally you can create and save to USB your own mask file for use later on – which can also be modified on a PC using any text editor software. Or for other monitoring options the external trigger socket on the read of the MSO can be configured to give a 5V pulse on a mask test failure.

If you have the LAN/VGA module you could place the MSO on in a lab or factory situation and monitor the testing over the network using a PC – very handy for QC managers or those who need to move about the workplace and still monitor testing in real time.

20MHz Function Generator/Arbitrary Waveform Generator (DSOX3WAVEGEN)

The “WaveGen” function is a versatile option that offers a highly controllable 20 MHz function generator and arbitrary waveform generator. It offers eleven different types of waveform: sine, square, ramp, pulse, DC, noise, sine cardinal, exponential rise and fall, cardiac and gaussian pulse.

The frequency can be adjusted between 100mHz to 20 MHz in 100 mHz steps; period from 50ns to 10s; full offset, amplitude and symmetry control; as well as logic level preset outputs (such as TTL, CMOS 5V, 3.3V etc.) Finally the WaveGen can be operated independently to normal measurement tasks, which is useful for ideal vs. actual comparisons and so on. Output is from the BNC socket at the bottom-left of the front pane and sync is also availble from the rear BNC socket. The arbitrary waveform generator is very simple to use  – and copied waveforms can be edited or have noise added to them to replicate real-world waveforms.

Power Measurement (DSOX3PWR)

This is a power measurement and analysis option that is integrated into the unit and provides a quick and easy way of analysing the reliability and efficiency of switching power supplies. It also includes a user license for U1881A-003 PC-based power measurement and analysis software that provides even more powerful insight into power supply measurement. With this option you can:

  • Measure switching loss and conduction loss at the switching device (to help improve efficiency)
  • Analyse dI/dt and dV/dt slew rate (for reliable operation)
  • Automate oscilloscope set-up for ripple measurements (to eliminate tedious manual oscilloscope set up)
  • Perform pre- compliance testing to IEC 61000- 3- 2 standards (to reduce compliance testing time)
  • Analyse line power with total harmonic distortion, true power, apparent power, power factor, and crest factor tests (to quickly provide power quality information)
  • Measure output noise (ripple)
  • Analyse modulation using the on- time and off- time information of a Pulse Width Modulation (PWM) signal (to help characterize the active power factor)
  • Measure how well a circuit rejects ripple coming from the input power supply at various frequencies with the Power Supply Rejection Ratio (PSRR) measurement.
For more indepth explanation of this option download and read the well written manual.

Etch-a-sketch

Well not a feature as such, but it exists if you know where to find it:

msoxes

Initial Conclusions

There is no doubt that the Infiniivision 3000-series are a great line of instruments. The waveform sample rate, memory size and bandwidth options are very competitive, and the ability to add various options is convenient and also helps lower the final cost for purchasing departments. (Start with the base model then hit them up for the options over time)

However there are a few things that could use improvement. Although the display is excellent – the right-hand column with “Agilent” at the top is always displayed. This is a waste of LCD space and there should be an option to turn it off, allowing waveforms to be displayed across the entire screen. If a $400 Rigol can do this, so should a $5000+ Agilent. The build unit of the unit is good, no problems are evident however it could be a little more “solid”; and the option of a clear shield for the LCD would be a great idea to protect against forceful and dirty fingers.

Furthermore the ground demonstration terminal suffers from metal fatigue very quickly, it already is somewhat chipped and may need replacing if you used it quite often. Finally, it would have been nice to see Agilent include the a carry bag – already people have asked to borrow the unit and to wander around with it in the box is somewhat awkward.

For those who rely on their test equipment will have the peace of mind that Chinese discount suppliers cannot give you – Agilent support exists and will not ignore you once a sale has been made. It doesn’t take long to find a tale of woe on an Internet forum from someone who imported their own “high-spec” DSO via eBay or direct east-Asian sellers only to find there are no firmware updates, competent English-speaking support or warranty of any kind. Furthermore, the ability to combine many functions in the one piece of equipment saves space, time and reduces your support channel back to one supplier. There is also an iPhone “app” that may be of interest – however as an Android user I haven’t tried it.

The saying “Quality is remembered long after price is forgotten” certainly holds true – and at the end of the day combined with the mix of standard and optional features at various price points – the Agilent Infiniivision MSO-X 3024A rises to the top echelon of test equipment.

 The Agilent Technologies Infiniivision MSO-X 3024A Mixed Signal Oscilloscope used in this review is a promotional consideration received from Agilent and element-14 via their Road Test program.

Agilent Test and Measurement equipment is available from your local element-14Farnell or Newark distributor.

Australian readers please note:  Trio Smartcal are the exclusive Australian Agilent distributors for all states except WA and NT – telephone 1300 853 407.

Measurement Innovation for WA and NT – telephone 08 9437 2550

High-resolution images are available on flickr.

Once again thanks for reading, have fun and keep checking into tronixstuff.com. Why not follow things on twitterGoogle+, subscribe  for email updates or RSS using the links on the right-hand column, or join our Google Group – dedicated to the projects and related items on this website. Sign up – it’s free, helpful to each other –  and we can all learn something.

Posted in agilent, DSO, MSOX3024A, oscilloscope, review, test equipment, tutorial

Review – Tenma 72-7222 Digital Clamp Multimeter

Hello readers

The purpose of this article is to examine the Tenma 72-7222 Digital Clamp Multimeter supplied for review by element-14/Farnell/Newark. The Tenma is a strongly featured yet inexpensive piece of test equipment – and considerably good value when you consider there is a current clamp for measuring high AC currents. So let’s have a look and see what we have.

Initial Impression

The Tenma arrives in a retail box, and generally nicely packaged. Naturally this has nothing to do with the performance of the meter at all, but at least they made an effort:

Opening up we find a nicely rounded group of items: the meter itself, some no-name AAA cells, test leads, a thermocouple for temperature measurement, a surprisingly articulate and well-written user manual, and the unit itself – all within a nice pouch. Wow – a pouch. Agilent? Fluke? All that money for a DMM and you don’t include a pouch?

Recent test equipment reviewers have made pulling apart the unit part of the review – so here goes… the back comes off easily:

No user-replaceable fuses… instead a PTC. A closer look at the PCB:

A very neat and organised PCB layout. There are plastic tabs that hold the PCB in along with a screw, however the case flexed too much for me to warrant removing the PCB completely. The spring for the clamp meter is locked in nicely and very strong, it won’t give up for a long time. Pulling the clamp base out reveals the rest of the PCB:

Installation of the battery is two stage procedure, first you need to remove a screw and then slide out the rear door:

… then insert the AAA cells into a frame, which is then inserted inside the unit:

The physical feel of the unit is relative to the purchase price, the plastic is simple and could be quite brittle if the unit was dropped from a height. The user manual claims the unit can be dropped from up to a height of one metre. Onto carpet? Yes. Concrete? Perhaps not. However like all test equipment one would hope the user would take care of it whenever possible. The clamp meter is very strong due to the large spring inside the handle, which can be opened up to around 28mm. The included leads are just on one meter long including the length of the probe:

The leads are rated to Category I 1000V (overkill – the meter can’t go that high) and 600 V Category II – “This category refers to local-level electrical distribution, such as that provided by a standard wall outlet or plug in loads (for example, 115 AC voltage for U.S. or 200 AC voltage for Europe). Examples of Measurement Category II are measurements performed on household appliances, portable tools, and similar modules” – definition from from National Instruments.  Unlike discount DMMs from unknown suppliers you can trust the rating to be true – otherwise element-14 wouldn’t be selling it.

Unit Specifications

  • Voltage Measuring Range DC:200mV, 2V, 20V, 200V, 600V
  • Voltage Measuring Range AC:2V, 20V, 200V, 600V
  • Current Measuring Range AC:2A, 20A, 200A, 400A
  • Resistance Measuring Range:200ohm, 2kohm, 20kohm, 200kohm, 2Mohm, 20Mohm
  • Temperature Measuring Range:-40°C to +1000°C
  • DMM Response Type:True RMS
  • DMM Functions:AC Current, AC/DC Voltage, Resistance, Temperature
  • Ranging:Auto
  • Display Count:1999
  • AC Current Range Accuracy:± (1.5% + 5d)
  • AC Voltage Range Accuracy:± (1.2% + 5d)
  • Accuracy:± (1.0% + 3d)
  • Current AC Max:400A
  • Current Range AC:2A, 20A, 200A, 400A
  • DC Voltage Range Accuracy1:± (0.8% + 1d)
  • Resistance Range Accuracy:± (1.0% + 2d)
  • Temperature Measuring Range:-40°C to +1000°C

The only measurement missed out on is DC current, however there is the Tenma 72-7224 which has DC current and frequency ranges. Finally, all the modes and buttons can be selected while holding the meter with one hand – for both left- and right-handed folk.

Measurement experience

Normally I would compare the measurements against my Agilent U1272A, however it’s out to lunch. Instead, a Fluke 233. First, AC voltage from the mains:

Next, a few DC voltage measurements:

Now for some resistance measurements. Higher values near the maximum of 20M Ohm can take around four seconds to measure:

Forward voltage of a 1N4004 diode:

dfv (1)

Now off to the kitchen for some more measurements – first with the thermocouple:

The boiling water test – 100 degrees Celsius (you can also select Fahrenheit if so inclined):

And now to test out the AC current clamp meter function with a 10A kettle at boiling point. First, using the 20A current range:

And then again on the 400A current range:

As always, it’s best to use the multimeter range that more closely corresponds with the current under test. The meter also has a continuity test with a beeper, however it was somewhat slow and would often take around one second to register – so nothing too impressive on that front. The meter can record the maximum value with the grey button, or hold a reading using the yellow button.

Conclusion

The Tenma 72-7222 works as advertised, and as expected. It is a solid little unit that if looked after should last a few years at a minimum. It certainly has a few limitations, such as the 1999 count display, lack of backlight, and the average continuity function. But don’t let that put you off. For the price – under Au$30 – it is a certified deal. If you need a clamp current meter for odd jobs or a casual-use multimeter and you are on a limited budget, the Tenma will certainly prove a worthwhile purchase. Full-size images are available on Flickr.

You can purchase a Tenma 72-7222 from element-14Farnell and Newark.

Thanks for reading! Have fun and keep checking into tronixstuff.com. Why not follow things on twitter, Google+, subscribe  for email updates or RSS using the links on the right-hand column, or join our Google Group – dedicated to the projects and related items on this website. Sign up – it’s free, helpful to each other –  and we can all learn something.

[Note – The Tenma 72-7222 Digital Clamp Multimeter was a promotional consideration from element-14/Farnell/Newark]

Posted in 72-7222, clamp meter, element14, multimeter, review, tenma, test equipmentComments (4)

September 2011 Competition

Competition over!

Posted in competition

Review – Agilent U1272A True-RMS Digital Multimeter

This is our review of the Agilent Technologies U1272A water and dust resistant digital multimeter. It’s an extremely well specifed instrument, and according to the Agilent promotional material a better alternative to the venerable Fluke 87V. We also have examined the Bluetooth module.

Initial impression

The retail box as always is impressive and well decorated. Opening it up reveals a range of items:

contentsss

including the meter itself, a calibration certificate and calibration results sheet, probe set, thermocouple, quick start guide and four AAA cells. It was a little disappointing to not find alligator clip adaptors nor a carrying case. For those interested, a full range  of documentation is available here.

The meter measures 207 x 92 x 59 mm (hwd) and is quite solid, not too heavy and surrounded by a good orange non-slip rubber layer. This no doubt helps provide some shock resistance, as this unit has survived a 2.5 meter drop from my ceiling to the concrete. It is refreshing to see that the keypad is laid out in an organised way, much better than the random-looking layout on the U1250 series:

meterss

The meter

Installing or changing the the battery (four AAA cells) is easily accomplished, and thankfully the fuses are also in the same compartment. The included AAA cells are thecheaper “GP brand”, and should do for the first few months. The dust and moisture protection is evident as shown by the o-ring seal around the perimeter of the compartment:

batteryfusecompartmentss

As mentioned earlier, the U1272A is water and dust resistant to IP54 specifications – 54 meaning “protected against dust limited ingress”/”protection against water sprayed from all directions – limited ingress permitted.”.

For more information about IP ratings and what they all mean, check out this IP-rating chart.

It is possible to turn the function selector with one hand whether you have the meter standing up or laying on your desk. The included test leads are just over 1200mm in length and are rated at Cat III 1000V, 15A. Two pairs of probes are included, with 4mm and 19mm tips:

leadsprobesss

Again, it is unfortunate that alligator-clip adaptors nor probes are included – these are very useful especially to those who are colourblind and need to sort resistors or measure tiny through-hole capacitors. Furthermore, a K-tyle thermocouple and non-compensation transfer adaptor are also included:

thermocoupless

The thermocouple’s temperature range is -20~200 degrees Celsius, however with an optional thermocouple the maximum temperature can be increased to 1200 degrees C. As for the othermeasurement ranges, they are detailed in the data sheet which you can download here (.pdf).

Furthermore there is a diode test  function, and a continuity beeper. The backlight also flashes when using the continuity function which would be very convenient for those working in a noise environment. There has been some discussion around various forums as to the speed of the continuity function, so here is a small video demonstration of it in action:

In use

Although readers would not have any problem using the meter without reading the manual, doing so will illustrate the particular features of the U1272A as well as operation of the menu system that allow various settings to be changed. These can include: beep frequency (!), backlight duration, data communication parameters, default temperature units, scale conversion values, and activating the low-pass filter available when measuring DC voltage and current.

At the risk of shortening the battery life, I extended the backlight duration immediately to thirty seconds; and set temperature units to degrees Celsius. When taking measurements that only require the main numeric display, the ambient temperature is shown in the secondary numeric display. I must admit to discovering another feature by accident, if the leads are in the current and COM terminals and you select a non-current measurement function – the meter will beep like crazy, blink the backlight and show an error message. This is useful when you’re tired and probably should be doing something else.

Measuring AC voltage provides various data upon request. Apart from the RMS voltage value, you can also turn on a low-pass filter which blocks unwanted voltage above 1 kHz.

The frequency measurement function allows the display the frequency, duty cycle and pulse-width when measuring AC or DC current or voltage. Furthermore, you can display both voltage/current and also display the frequency, pulse-width and duty cycle at the same time, for example:

freqvoltss

In a previous article the U1272A was used to measure frequency and duty cycle, which you can observe in the following short clip:

Measuring DC voltage is straightforward, and there is also the option to measure both AC and DC components and display them combined or separately, for example:

acvoltdcoffsetss

You can also display voltage as a decibel value relative to 1 mW (dBm) or a reference value of 1V (dBv). And the dB reference impedance can also be set to fall between 1 and 9999 ohms. Another interesting voltage measurement function is “Zlow”. Using this function, the meter changes to a very low input impedance, and can remove “ghost” voltages from the measurement by dissipating the coupling voltage. This function can also be used to test if a battery is still usable, if the voltage of the battery under test decreases slowly, it doesn’t have the capacity to deliver the required voltage. However I wouldn’t put a battery under this test method for too long due to the meter acting close to a short circuit.

Measuring resistance is simply done with the U1272A, and for more precise measurements one can short the probes to measure their resistance then set a null point so your measurements will not be affected by probe resistance. There is also an Agilent feature called SmartOhm which can be used to remove unexpected DC voltages that can add errors to resistance measurements. You can also use SmartOhm to measure leakage current or reverse current for junction diodes. I look forward to spending more time examining SmartOhm.

Furthermore, one can also measure conductance (the reciprocal of resistance) which is measured in Siemens. According to the manual one can measure extremely high resistance values up to 100 gigaohms. Interesting.

Diode measurement works as expected, the standard setting displays the voltage drop across the diode. However by pressing Shift on the meter, you can use the “Auto-diode” function which forward and reverse bias simultaneously using both numeric displays. For example, measuring a 1N4004 diode produces the following display, the forward voltage and the Good/Not good result:

autodiodess

Measuring capacitance is also quite simple, and the manual recommends setting a null value while the probes are open to compensate for residual capacitance. Interestingly the LCD shows when it is charging and discharging the capacitor under test, using the following segments:

capsegss

Temperature measurement is possible with the included thermocouple and adaptor. Note that the included K-type thermocouple is only rated for up to 200 degrees Celsius, however with an optional unit the meter can measure up to 1372 degrees C. The display can show Fahrenheit as well as Celsius. The meter also shows ambient temperature using the secondary numeric display when it is not in use with other measurement display functions. Finally, measuring AC or DC current is completed as expected, and as noted earlier when switching to another non-current function, the meter will remind you to change the positive lead.

Compared to other meters, there are a few things that irritated me slightly with this unit. The auto-ranging can be somewhat slower than other meters, especially the frequency measurement – it can take around four seconds to measure a constant frequency… my old Tektronix CFC-250 is faster than that. And the exclusion of alligator-clip adaptors and case was disappointing considering the price of the meter. However on a positive note, the meter is supplied with minimal paper documentation, and a full range of manuals, service guides and so on are available for download from the Agilent website.

Update – 14th June 2011

Turns out that many people had similar (and other problems) to myself with their U1272A. They can be solved by updating the firmware via the USB cable. Agilent will send owners of early versions with the affected firmware a free USB cable in order to fix it up. Download this .pdf file with the instructions on how to receive the cable.

Update – 20th June 2011

The USB>DMM cable has arrived and the firmware updated to v2.0. The meter now works as expected – very well. Kudos for Agilent for taking ownership of the problem and sorting it out so rapidly.

Over the last three months I have been using the U1272A and would call it a success. The dual line LCD display really is useful, as well as the low current measurement and especially the Zlow function. There is a short video you can watch that explains a few of the unique features very well. Furthermore, there is a distinct lack of fragility which gives you one less thing to worry about when looking after your tools. Finally there is also the data-logging, however this does require an optional cable. If you are in the market for a full-function electronics multimeter, put this meter on your evaluation list.

As always, thank you for reading and I look forward to your comments and so on. Furthermore, don’t be shy in pointing out errors or places that could use improvement. Please subscribe using one of the methods at the top-right of this web page to receive updates on new posts, follow on twitter, facebook, or join our Google Group.

High resolution images are available from flickr.

[Disclaimer – the Agilent U1272A in this review is a sample made available by Agilent Technologies via element-14]

Posted in agilent, android, bluetooth, multimeter, review, test equipment, tutorial, U1177A, U1272AComments (2)

Review – Fluke 233 Remote Display True RMS Multimeter

Hello readers

Several followers of my website have noticed the use of an interesting multimeter in a few of my articles, and were curious about it. So in this article we will discuss it in more detail. It is certainly novel in design, and has proven to be very convenient in use – the Fluke 233 remote-display true RMS multimeter. It arrives in a cardboard box that is easily recycled:

boxs

Upon tearing open the packaging we are presented with the following contents:

contentss

The contents of the box are as follows:

  • The meter itself;
  • a long (~1.2m) pair of Cat IV leads with very sharp points;
  • matching insulated alligator clip adaptors;
  • a K-type thermocouple;
  • a printed Getting Started manual, and the complete manual on CDROM;
  • a single, universal getting started sheet – explains how to remove battery isolation tabs.

However, a carry case was not included. Considering the cost of the meter here (Au$550 + tax), one would have expected a case. On the other hand, if you/your workplace can afford a 233, you can pay for your own case. So there’s two angles to the case perspective.

It is good to see that there isn’t too much of a printer manual, the less paper used the better. As others have said, if you have one of these meters the manual isn’t necessary apart from checking the specifications, and the same applied to myself. Thoughtfully the meter is supplied and fitted with 5 x AA Duracell alkaline cells, three in the meter body and two in the display unit. All one needs to do is pull out the plastic tabs from the battery compartments, and you’re ready to go.

Physically the unit does not disappoint. Made in the USA. First class. Another solid Fluke design, clean lines, and a great fit and finish. Futhermore it is of a good weight, so you could always bang in a nail with it, or the pointy-head boss. The exterior has the rubber-moulded housing which is not removable, however this would be recommended for the target market – as the 233 would be more of a field work than a test-bench instrument. However, if you do sit it on the bench with the tilting bail, you can still operate it with one hand as it has enough friction to stay put. It is also good to see that the box and packaging are cardboard which is easily recycled.

After flicking the meter on the first thing to do was remove the display, plug in the thermocouple, and toss the body into the freezer:

freezer-tests

Even with the meter in the freezer, I could still move the display around 1.5 meters away and it still received the data signal. Notice how the display is on the freezer door – it is magnetic. Immediately the benefits of the remote display come to mind. You can always have the display right where you want it, and the meter where it needs to be… it’s win-win. After showing it to my auto-electrician friend, she didn’t want to give it back.

The ability to set up a meter in a less than perfectly safe environment and take the display away is almost priceless. Furthermore, the backlight is a nice even blueish colour, and times out after around forty seconds. Whilst in the kitchen, I tested out the external temperature of my tea:

teas

Using the meter in general is very simple, you can hold it in one hand and select all of the functions with your thumb. Having the yellow shift key makes changing between associated readings very simple, for example after reading AC voltage:

241vacs

Then pressing the shift key changes to frequency:

50-hzss

The meter has several useful indication functions – while working with high voltages the triangular market is illuminated; when changing to temperature you are prompted with “OPEN” for the thermocouple, and changing to current you are prompted with “LEAD” to change sockets. It is obvious after a short period of time this was designed by engineers for engineers, and not made to a ‘price’. Although this is not an electronics multimeter, it still has quite a few ranges that would suit at a pinch. Plus the one-touch data hold, minimum and maximum functions are included as with other top-end Flukes. Hopefully someone at Fluke is working on a remote display version of their 87V.

Now that I have had this meter for just over five months, it has already become a worthwhile addition to my bench. For the kind of work I do, it has already replaced another multimeter, my old frequency counter and thermometer. The ranges are quite useful, and the continuity beeper is in the display not the body. According to the manual the 233 is rated for a one meter drop onto any of the six surfaces. Out of respect to the meter I will not throw it into a river or from a moving car. The other factor that prevents me from going to such extremes is the clear plastic over the LCD – there is a small amount of ‘give’ or flexibility in that area. Otherwise the 233 is as solid as they come.

The specifications can be found in detail in the manual here, however a quick glance shows:

Range                                                             Accuracy

AC voltage: 0.1mV ~ 1000V                      1~2%+3

AC current: 1mA ~ 10A                               1.5%+3

DC voltage: 0.1mV ~ 1000V                     0.25%+2

DC current: 1mA ~ 10A                               1.0%+3 ** no microamperes

resistance: 0.1 ~ 40 meg-ohm                   0.9~1.5%+2

frequency:  0.01 Hz ~ 50 kHz                    0.1%+2

capacitance: 1nF to 9999 uF                     1.9%+2

temperature: -40 ~ 400 degrees Celsius     1%+10

And there is also a diode test and continuity beeper function. Interestingly enough, I discovered by accident that the frequency counter function was slightly underrated. Some more testing showed it was good for up to 99.48 kHz:

233_freq

Not bad at all. However as with the many pros, there are  a few cons to using this meter. The auto-zero time of the display is a little slow, sometimes it can take two seconds. That doesn’t sound like much, but when you’re measuring many components the time adds up. And the LCD is not protected as well as expected, you can push into it with your finger. For a Fluke meter, one would expect it to be much more solid – if the display unit fell from a height and landed on something pointy with the display facing down, it would be ruined. So be careful if you have one.

Furthermore, the battery life is around eight to ten weeks of “daily use” (perhaps seven hours a week, usually with the backlight on). Some have said this is bad, however my opinion is that the convenience of the remote display makes up for the shorter battery life.

However at the end of the day – this is a great tool. Being able to measure something outside your field of vision, and having the results in front of you is incredibly useful. You could achieve the same functions by using a meter with a PC interface, but that can be overkill and time-consuming to set up. So if the specifications of the 233 meet your needs, this is a great tool that will serve you very well.

The Fluke 233 Remote Display True RMS Multimeter is available from your local element-14 or Fluke distributor.

As always, thank you for reading and I look forward to your comments and so on. Furthermore, don’t be shy in pointing out errors or places that could use improvement. Please subscribe using one of the methods at the top-right of this web page to receive updates on new posts. Or join our Google Group.

[Disclaimer – the Fluke 233 is a review sample made available by Fluke via element-14]

Posted in 233, fluke, learning electronics, product review, test equipmentComments (6)


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