Meatest M550 User manual

M550 Impedance calibrator is designed for LCR meter verification and calibration. The calibrator integrates
partial resistance standards in decade series with range of values from 100 mup to 100 M, capacitance
standards with range from 10 pF up to 100 µF and inductive standards with the range from 10 µH up to 10 H.
For test leads and unit under test electrical zero compensation the calibrator is equipped with reference
positions of short-circuit terminals SHORT and open-circuit terminals OPEN. Summary frequency range
covers band from 20 Hz up to 1 MHz, however some partial standards have lower applicable frequencies.
Partial standards feature low temperature coefficient, excellent long term stability and low frequency
dependency.
The calibrator offers two banks of standards. The more accurate bank is equipped with four output BNC
connectors. It is aimed for calibration of LCR meters based on auto-balancing bridge principle using four-
pair-terminal technique (4TP) of test terminal connection. The second bank (4W/2W) is equipped with 4mm
output banana terminals and it’s aimed for calibration of LCR meters based on I-V method with non-coaxial
test terminals. Practically this bank can be used in four-wire (4W) or two-wire (2W) measurements.
M550 has a built-in test signal level meter which can be easily used for verification of test signal voltage,
current and frequency. Color LCD display shows parameters of a selected standard, set-up configuration,
calibration data accuracy and other useful information.
Impedance calibrator should be periodically recalibrated. Recommended recalibration interval is 1 year.
Internal calibration data are accessible via front panel keyboard. Calibration memory is protected with a
calibration password.
All functions of the calibrator can be controlled by IEEE-488 interface or via RS-232 serial line.

Main control segments of the calibrator are:
1. Output terminals –Calibrator contains two sets of output terminals. Both sets are electrically isolated
from each other.
4TP –coaxial BNC output for calibration of BNC terminal LCR meters. Shielding of the BNC
connectors is isolated and connected together inside the bank of standards in one point to obtain the
lowest frequency dependency. 4TP output is suitable for calibration of LCR meters with coaxial input
connectors.
4W/2W –4mm banana non-coaxial output for calibration of four and two wire LCR meters. While in
4W mode all four terminals are applied for DUT connection, in 2W mode only HCUR and LCUR
terminals have defined impedance parameter.
Note: In 2W mode both HCUR –LCUR and HPOT –LPOT terminals are connected to internal partial
standard however calibration values are defined between HCUR –LCUR terminals.
Meaning of individual terminals is as follows:
HCUR high source current terminal
HPOT high sense voltage terminal
LPOT low sense voltage terminal
LCUR low sense current terminal
2. Display –More in chapter 1.1.1.
3. Numeric keys –Numericalvalues can be entered from the keyboard. ENTER button is used to confirm
the selection. CANCEL button is used to cancel the entry.
4. Function keys –Function buttons can be used to call up the functions of the calibrator directly.
5. System keys –Group of buttons enable access to system parameters
6. Selection of output mode –The buttons enable selection one of two outputs either 4TP or 4W/2W and
switching output terminals ON/OFF.
7. Rotary knob –The rotary knob integrates several functions. By turning the knob to the left or right,
the user can:
-Step through the options in menus
-Select L-C-R partial standard according to its nominal value
-Enter numerical values
When making a menu selection, pushing in on the knob is equivalent to pressing the SELECT soft
key. When editing a number, pressing in on the knob will switch between moving the cursor between

characters and changing the selected character’s value. Arrow icons above and below the selected digit
indicate which of the two modes are active.
8. Soft keys - There are five buttons below the display, which meaning changes depending on the content
of the display. These buttons usually call up local menu with parameters setting, modes, etc. or enable
to close currently opened function or menu.
9. Guarding terminal –Guarding terminal. It is connected to shielding of the 4TP coaxial output
connectors. It has no function in 4W or 2W mode.
10. Grounding terminal –Grounding post is joined to metal parts of housing and to protective earth in
power line socket.
Display is divided into several sections with following meaning:
1. Information line from left to right:
-Type of selected bank Resistance, Capacitance, Inductance
-Current date/time. Displaying of the date and time can set to be hidden in setup menu.
-Local/remote mode status indication tooltip. Shows additional information about selected
parameter or main value. Information may include uncertainty, range, description, limits (burden
current, compliance voltage), etc. Tooltip is hidden when no parameter is selected.
2. Auxiliary parameter field from top to bottom:
-Status of output terminals ON or OFF
-Selected output terminals and basic mode 4TP or 4W/2W indication
-Calibration uncertainty of the selected standard at selected frequency
-Parallel or serial equivalent circuit of the displayed calibration values
-Working mode of built-in test signal level meter ON/OFF
3. Soft button line:
-Soft buttons description. If there is no description above soft button, the button is not active in
selected function.
4. Meter reading. Main parameter field from top to bottom:
-Both main complex parameters of selected standard in selected frequency point including type of
displayed values. In the upper line primary parameter, in the bottom line secondary parameter is
always displayed.
-Indication of function CORRECTION ON or OFF. Symbol “corr” is displayed beside the main
parameter if Correction is ON.
-Z/θ normalized polar format calibration values of the selected standard

-Selected (or measured) test frequency
-Measured test voltage and frequency sourced by DUT
-Calculated test current
Common rules are used for an applied color of labels and values.
-Red color is applied, when displayed value is measured by M550 calibrator.
-Blue color is applied for parameters or values, which can be set up or modified
-Black color is used for fixed values, labels, notes, parameters which cannot be modified and for
other fixed text with a general information purpose.
There is located power line socket, power line fuse and power line voltage selector 115/230V integrated in
power entry module, interface connectors GPIB, RS232, metal central grounding post and four coaxial
connectors for external standard (function EXT).
1. Power entry module with power line switch, power line with fuse and voltage selector
2. Model plate
3. EXT input with BNC connectors
4. Ventilation hole
5. RS-232, GPIB connectors
6. Central grounding post
Every M550 Impedance calibrator delivery includes following items:
-USB stick with user manual 1 pc
-Mains supply cord 1 pc
-Coaxial cables BNC-BNC 4 pcs
-Test lead banana-banana 4 pcs
-Adaptor BNC/banana 4 pcs
-Spare fuse 1 pc
-RS232 cable 1 pc
-Test report 1 pc

The calibrator can be integrated into automated calibration systems (ATS) and generally controlled from
remote computer via following remote control interfaces:
-RS232
-GPIB (IEEE488)
When controlled remotely, maximum ratings of calibrator’s output signals as well as all other specifications
are the same as in manual mode.
Meatest software package WinQbase + Caliber is recommended for best automation results. This system is
designed for automated and semi automated calibrations of digital and analogue meters including uncertainty
calculation, result evaluation and certificate printing according to ISO 17025 standard.
Only one interface can be used for communication at any given time. Default active interface is RS232, other
interfaces can be selected in MENU->Interface->Active interface. To establish connection between the
calibrator and computer, set interface settings in your computer accordingly:
-COM port see available COM ports in Windows Device Manager
-Baudrate RS232 according to MENU->Interface->RS232 Baudrate (9600 by default)
-Data bits 8
-Stop bits 1
-Parity None
-Handshake (XON/XOFF) Off
-GPIB Address according to MENU->Interface->GPIB Address (2 by default)
See M550 SCPI manual for complete SCPI reference, more details on communication setup and
troubleshooting.

Inspect package contents when unboxing the calibrator for the first time. See chapter 1.3 for complete list of
accessories.
Place the instrument on a level surface before powering on and let it stabilize for at least one hour if the
instrument has been stored outside of reference temperatures beforehand.
The instrument has been designed in Safety Class I according to EN 61010-1. The design reflects the
requirements of A2 amendment of the standard. Safety is ensured by the design and by the use of specific
component types. The manufacturer is not liable for the damage caused by modification of the construction or
replacement of parts with non-original ones.
Safety symbols used on the equipment:
Warning, risk of danger.
Warning - risk of electric shock. Hazardous voltage above 50 V DC or AC
might be present.
See User Manual.
Protective earth.
Fuse.
To prevent possible electrical shock or personal injury:
-Read carefully safety information before you use the Product.
-Do not alter the Product and use only as specified, or the protection supplied by the Product can be
compromised.
-Do not use the Product if it is altered or damaged.
-Use this Product indoors only.
-Use power cord approved for local mains voltage and plug configuration and rated for the Product.
-Keep hands away from all Product terminals and exposed metal cable parts during operation. High voltage
on those may be cause death or serious injury.