The nuts and bolts of what is MET/CAL and what it can do.

MET/CAL is a software program developed by Fluke to semi/fully automate the calibration process of almost anything that needs calibration, whether its just an in house performance test or a full blown ISO 17025 verification including uncertainty calculations.

First release was to the best of my knowledge was around 1989 and it has been continually updated to meet the ever growing demands of calibration labs ever since, till today where there is also MET/TEAM which is a database program that can mange and handle all of your calibration lab needs from receiving right through to billing and also sending out email reminders automatically. Both MET/CAL and MET/TEAM work very well together as to be expected.

MET/CAL uses a whole array of commands to control how things get done, what questions get asked and how results and other things like uncertainty are calculated, these commands are called “Function Selection Commands” – from here I will refer to them as “FSC’s”.

The heart of MET/CAL are things called procedures, they contain all the FSC’s to run the tests etc, these are written up inside an add on program called “MET/CAL Editor” handy aye. These procedures can then be turned into projects, called PXE’s these are files that can just be double clicked and they will launch MET/CAL and run.

MET/CAL also has the power to open other files i.e. an Excel spreadsheet and then to read/write to them, grab times and dates from the operating system, temperature values from external devices via any communication protocol. It can even configure itself via operator prompts to determine what com port to use etc. See example below:

Ask the operator what com port the UUT is on and put value into register “MEM”.
1.011 MEMI ENTER PORT NUMBER THAT UUT IS ON:
Make a string register called “COMPORT” and put the value “COM#” into it.
1.012 MATH COMPORT = “COM#”
Modify the value “COM#” to be “COM and whatever number you put into “MEM” i.e “COM4”
1.013 MATH COMPORT = REPL(“#”,MEM, COMPORT)
Assign the com port to any future “PORT” FSC’s inside the procedure unless overridden.
1.014 VSET PORT = [V COMPORT]

As you can see from the above, three different FSC’s are used to set which port MET/CAL will use to run the procedure. These are MEMI,MATH and VSET (VSET is a very powerful one this controls a lot and also defines how uncertainty is calculated). I plan to cover VSET a lot more at the CPS MET/CAL user group days in MAY 2016.

Lets quickly look at the MATH FSC as this one is also very powerful and used A LOT. At a very basic level the MATH FSC is used to preform math (Fancy that). See example below:

Generate a string register called “MATH” and assign the result of the math to it.
1.001 MATH MATH = 1 + 2

Now lets try something a bit more involved:
1.001 MEM2 ENTER YOUR BIRTH DATE IN DD-MM-YYYY
1.002 MATH DAY = DATE (“DD”); MONTH = DATE (“MM”); YEAR = DATE
 (“YYYY”); DAY1 = FLD (MEM2, 1, “-“);
1.003 MATH MONTH1 = FLD (MEM2, 2, “-“); YEAR1 = FLD (MEM2, 3, “-“);
1.004 MATH S[5] = YEAR – YEAR1; S[6] = S[5] – 1
1.005 IF DAY1 < DAY && MONTH1 < MONTH
1.006 DISP YOU ARE [S5] YEARS OLD
1.007 ELSEIF DAY1 > DAY && MONTH1 < MONTH
1.008 DISP YOU ARE [S5] YEARS OLD
1.009 ELSEIF DAY1 > DAY && MONTH1 > MONTH
1.010 DISP YOU ARE [S6] YEARS OLD
1.011 ELSEIF DAY1 > DAY && MONTH1 == MONTH
1.012 DISP YOU ARE [S6] YEARS OLD
1.013 ELSEIF DAY1 == DAY && MONTH1 == MONTH
1.014 DISP HAPPY BIRTHDAY YOU ARE [S5] YEARS OLD
1.015 ENDIF

In the above example MET/CAL asks the operator what their birthday is, in a certain format then looks up what the date is on the current operating system and based on some conditions will calculate your age and even wish you happy birthday if the days and months match up. So as you can see you can also setup conditional steps i.e. you only want to test the DC voltage function this time round and not all the functions.

I feel the best thing about MET/CAL is however the ability to control almost any piece of reference equipment if it has a com port connection on it, be it RS232 ,IEEE-488 or even USB, this takes the operator away from the expensive gear and eliminates possible operator error. MET/CAL has come up with a whole array of special FSC’s to match just about every piece of Fluke reference equipment and even non-Fluke ones like the HP3458A and Agilent/Keysight stuff, and if its not in the default list the user can still control it via “PORT” commands. It also handles manual standards very well like resistors and you can assign “Accuracy” files around these standards, so one can calculate uncertainty budgets when using said manual standards without having to open excel…..Come on I know thats how you all do it.

So below you can see how to setup a Fluke 5730A to output -190.0 mV

1.003 5730A +Voltage = -190.0 mV

And also a manual standard i.e. a 1 ohm resistor 1.004 STD Fluke 742-1

So for this procedure to execute you will need both a 5730A and a 742-1 setup and both with a valid calibration in your database.

But wait theres more…….As you can see from all of the above that MET/CAL is geared around doing electrical based calibrations which to be fair was why it was developed in the first place. And it is very good at it, but it can also be used to perform manual calibrations of say pressure or temperature.

You could tell it to control a dry well temperature source by setting the desired temp and then checking for stability, take a reading from your temperature reference and the UUT and compare the two. Then decide if the result is acceptable or not or just write the results to a file for the technician to evaluate later, once all the test points are complete. When test has been completed set the dry well to park mode (no control)……Fancy calibrating a temperature device while you sleep?

1.015 PORT SOUR:SPO 50
1.016 PORT OUTP:STAT
1 1.017 DO
1.018 PORT SOUR:STAB:TEST?[I]
1.019 UNTIL MEM>0

Or lets look at pressure….say a 100 bar 1% analogue gauge using a Crystal XP2i digital gauge as your reference.

Tell your technician to apply a said pressure. Then read your digital reference gauge, extract the value and put it into register “MEM1” and finally evaluate it based on a 1% of 100 bar..

1.001 DISP APPLY PRESSURE TILL UUT IS READING 100 BAR
1.001 DISP CLICK ADVANCE ONCE ITS STABLE
1.002 PORT ?PRE [I$]
1.003 MATH MEM1 = FLD(MEM2,1,”,”)
1.004 MATH MEM = 10
1.005 MEMCX 100 ‘bar’ 1/

No more worksheets –  No more excel – No more potential operator error with data entry – No more hoards of paper. Calibrate while you sleep – No more having to rely on highly skilled techs to preform basic calibrations.

Personally I haven’t found a problem MET/CAL can’t solve. I view it as a calculator on steroids with the added bonus of being able to control instruments and manipulate data on the fly.

And imagine if your UUT has a com port……Fully closed loop calibration. Setup and walk away as the ad says.

This is just a very basic outline of what it is and what it can do these examples are very basic level stuff…..I hope to go a whole lot in depth when you come along to the CPS MET/CAL days in May 2016….If you use it or if your sick of not using it (still plugging away with worksheets and excel) come along bring your issues/problems and hesitations and we will solve them for you.

Once again “Personally I haven’t found a problem MET/CAL can’t solve.”

See you in May