Figure 1 - Equipment set up (Back: Variac, Isolation Transformer, PA1000 Power Analyser, Front: BB1000-NA breakout box)
Many thanks to Tektronix and element14 for giving me privilege and opportunity to road test the Tektronix PA1000 Power Analyser.
I've prototyped, built and repaired many power supplies over the past three decades to find how the PA1000 Power Analyser can accomplish productivity gains. With all due respect to the sponsors this road test is an honest appraisal and will highlight the benefits, deficiencies and all observations with the equipment provided. I hope the reader will enjoy this road test and benefit from it.
The PA1000 comes in a neat robust metal case that measures 102mm x 223mm and 285mm (H x W x D) and weighs 3.2kg making it easily portable. It has a handle that is lockable in several position and also acts a desktop stand. Due to the hazardous voltages being monitored thus the PA1000 may be operated only be qualified personnel who are aware of the associated safety, operation, connection and first aid procedures. Page 4 of the Operators manual outlines these requirements in more detail. The front panel consists of a 320 x 240 pixel TFT Liquid Crystal Display along with 18 buttons, power switch and 6 connection terminals.
The BB1000-NA breakout box comes in a sturdy plastic box to act as an insulation barrier that is suitable for its task but is not as durable or tough as the metal case. If used in the field will be prone to be knocked and scuffed about but there should be no such issues when used in an electronics workshop or laboratory.
Figure 2 - The supplied Test Leads with alligator clips attached.
The PA1000 is supplied with a set of 1000V, 32A Cat II, UL 61010 complaint Test leads with removable alligator clips, software and manual CD and accompanying paper work including a calibration certificate.
In March 2013 Tektronix acquired the Voltech's Power Analyser technology and the Tektronix PA1000 Power Analyser has its genesis from the Voltech PA1000. Details of this technology transfer is published at Tektronix Enters Power Analyzer Market | Tektronix and is evidenced by PA1000 Help screen where remnants of its Voltech genesis still exist.
Figure 3 - The Voltech reference
Unlike standard OEM branding where the only changes are just cosmetic changes the PA1000 and BB1000 Breakout box accessories have been modified. The USB Type A host port for hosting a memory stick has been moved from the rear panel to the front panel. The parallel printer, serial and service ports have been removed from the rear panel. The GPIB port, Ethernet port, USB Type B port and earthing attachment point remain but are in different locations. The front panel external shunt connections and sockets have changed. The colour of the 4mm input sockets have changed to red, blue and black to align with the breakbout boxes for clearer interconnection and the PA1000 now contains two internal current shunts - the original for normal range (1A-20A) and low range (< 1A) that was previous contained within the Voltech breakout box.
Figure 4 - Not the usual Tektronix corporate logo.
Figure 5 - Front Panel comparison
Figure 6 - Rear Panel Comparison
The original Voltech Breakout box was a universal power standard design that contained a switchable low range current shunt. Rather that doing the same Tektronix has released 3 different versions of breakout box designed specifically for the North American, European Union and United Kingdom domestic power connector standards. These new breakout boxes are colour coded to match the Tektronix PA1000's new terminal colours and do not contain a switchable current shunt because it is now contained within the PA1000.
Figure 7 - Breakout Box Comparison
I received a North American version of the breakout box (BB1000-NA) and I needed to open it up and check its suitability for 230VAC because its attached compliance labels specify a maximum of 125VAC @ 50/60/400Hz. Interestingly the internal wiring uses the EU (& UK) colour code standard with Brown for Active, Blue for Neutral, and striped Green/Yellow for Earth. The IEC 320 input power connector system ensures that the power signals are connected up to the correct terminals. A compliant travel adapter used must ensure that the output socket pins remain correctly wired ensuring that Active is still connected Active, Neutral is connected to Neutral and Earth connected to Earth. For the case of an Australian plug conversion to USA plug (in fact the same for EU and UK) the physical positions of the Live and Neutral must be transposed.
The 400Hz input frequency is interesting because the normal power 125VAC frequencies are 60 & 50 Hz. It means it can handle Aircraft power that operates at the higher frequency to reduce the bulk and weight of any associated transformers.
I have a handy tool that I used for testing socket wiring. It consists of 3 lights and its output combinations signifies the following;
- No Neutral
- Active and Earth Reversed
- Active on Earth and Earth not connected
- Active on Earth short or Polarity reversed
- No Earth (Note: This is the expected state when using an Isolation Transformer)
Australia's power standard and connector selection is an interesting. It is now specified to match the nominal EU voltage of 230VAC 50Hz but for many years was specified as 240VAC 50Hz but in reality is realised as a range of nominal voltages from 230 to 254 volts. The Australian domestic 10A connectors were designed in 1930's based upon USA flat pin connectors of the time. The main selection reason was the cost and ease of manufacture. The flat pin connectors were could be easily be pressed and folded from sheet brass. Wall receptacles were always switched for safety. The Active and Neutral terminals are angled at 30 degrees to ensure that the plug can not be inserted upside down into a wall receptacle. The Earth pin longer to ensure that it is connected first upon insertion and remains connected longest upon removal. The connectors have evolved to now include partially insulated terminals (like the EU plug) for the Active and Neutral pins to prevent a conductive object falling and shorting them for additional safety (China addressed this by using the same connector upside down with the Earth pin on top). Connector variants exist for other power ratings and uses and are deliberately designed not to fit the standard consumer version (10A). One variant uses a round earth pin and others have enlarged terminal pins.
As a bit of trivia Argentina uses the same connector but with slightly longer pins.
Figure 8 - Wall Receptacle Comparison
It is interesting to note that the position of the Active(aka Hot or Live) and Neutral pins for the USA configuration are in the transposed positions used for EU, UK and Australia (relative to the Earth pin and its orientation). Many traveller adapter plugs just change the format of the connector without addressing this transposition by using straight through connections and are potentially dangerous.
Figure 9 - Ballast Breakout Box and Current Clamps
There is a range of accessories for the PA1000 to allow it to be used for a large variety of conditions. This includes a specialty current transducer for lamp ballast testing and two current clamps to handle higher current ranges 200A and 1200A. Unlike the breakout box and standard connections these optional current clamps connect to the external shunt input terminal.
When working on power equipment it is always important to follow safety procedures. Although the PA1000 is isolated from the DUTs (device under test - aka EUT(equipment under test) and UUT(unit under test) Active and Neutral signals, the DUT is not isolated from the mains power supply and nor its Protective Earth. This is perfectly fine for monitoring fully enclosed equipment but when using equipment with its covers off additional safety measures need to be taken. To protect personnel from the shock hazard of an unwanted Earth loop (e.g. through the test equipment, PA1000 case or technician,) an isolation transfer can be used to decouple the DUT's power source from the mains supply and Earth.
For extensive voltage input range testing a Variac (Autotransformer) is also useful. It allows the input voltage to range from 0 - 110% of the mains input voltage. In my case 0-260VAC. When used in conjunction with an isolation transformer a variable and isolated voltage can be provided to the DUT. There is a debate on the order of how these are connected. It is common to have the isolation transformer connected to the mains input with the Variac connected downstream just prior to the DUT as this allows the isolation transformer to operate at its nominal voltage. The downside is that the protective steel casing of a portable Variac and DUT's Earth is not longer connected to protective Earth so appropriate safety measures must be followed (such as ensuring that their metal cases are not in contact with each other).
The current sensor within the PA1000 is very sensitive and was affected by my Isolation transformer's proximity so I needed to move the PA1000 a sufficient distance away (centimetres) from it to remove its influence.
The Tek.com website for the PA1000 was browsed and updated firmware, firmware updater and the PWRWARE application downloaded and installed. The PA1000 Firmware was brought to version 1.001.006 (The help screen reference to Voltech was xxxx).
Figure 10 - Updated Caption Screen showing new firmware level but no new logo.
Figure 11 - Updated Help screen now referring to www.tek.com
Usefulness and Ease of Use
The PA1000 is a very useful piece of test equipment for those workshops and laboratories that often deal with power supplies or for field compliance and energy efficiency auditing. Its isolated sensor inputs in conjunction with breakout box makes for a simple, quick and safe attachment.
Instead of having a both Voltmeter and Ammeter or an oscilloscope with high voltage probe and current probe and the complexity of attaching it to the DUT, the PA1000 connects really easily to the input. This allows the oscilloscope, voltmeter and ammeter free to be used for other circuit measurements.
After ensuring that the mains power wall receptacle (or isolation configuration) is wired correctly the standard connection procedure is as follows;
- Make sure PA1000 is properly connected to its power source and Earth.
- Decide which measurement range to use - Normal or Low - This determines which AHI terminal to use. (Normal (20A RMS) = AHI, Low (1A RMS, 2A peak) = A1A)
- Plug in Breakout box breakout points into PA1000 input terminals using the insulated 4mm test leads. (Red = VHI, Blue = AHI, Black for VLO and ALO)
- Plug in Breakout box output to DUT
- Depending upon the connection configuration - Connect Earth from rear of PA1000 to the DUT as necessary.
- Switch off power at wall receptacle
- Plug in Breakout box input to mains supply
Now you ready to switch on the power at the wall receptacle and DUT to make measurements.
The configuration of the PA1000 is done through its consistent menu system. The PA1000 does not have a touch screen LCD so navigation is performed using the 4 buttons immediately to the right of the LCD.
The icons displayed immediately to the left of the buttons indicate the current function of each button.
The sequence used to select the Current Shunt is as follows;
Press the MENU button
Now the Root menu appears
Press the Down arrow button twice to highlight Inputs
Press the Right arrow to select this item.
Now the Input Sub menu appears
Press the Down arrow button four times to highlight Shunts
Press the Right arrow to select this item.
Now the Shunts Sub, Sub menu appears
Highlight the desired option using the Up and Down arrows
Press the Tick button selected the option
You can now press the MENU button to exit back to the normal display or Left Arrow button to navigate back one menu.
Testing Normal Operation
When testing certified products there is no need to connect up an isolation transformer. Mains Power is connected to the Breakout box's input and the DUT connected to the Breakout output connector.
To confirm a safe connection prior the connection of any device I connect my plug wiring tool to confirm that the wiring is safe. This requires the mains power to be switched on for the test and switched off prior and after the test.
Figure 12 - The illuminated Green and Red indicators confirming correct power wiring and ready for testing.