MEATEST
M-140 Multifunction Calibrator
Operation manual v46
81
Verification test
Procedure recommended for verifying parameters of the calibrator is described in this chapter. During tests it is
not necessary access to the interior of the instrument.
Required equipment
Following instruments are required for performance verification test:
•
81/2 digit multimeter type Agilent HP3458A or Fluke 8508A or other type with accuracy 0.001 % on DC
voltage
•
resistance shunt 10 m
, 100 m
Burster 1280, or other type with accuracy 0.01%
•
RLC meter BM 595, HP 4263A, HP4278A, ESI 2150, or other with accuracy 0.1 %
•
counter HP 53181A, HO 53130, BM 642 or other with accuracy 0,001 %
•
powermeter 0.02- 0.05 % like Zimmer LMG95, Yokogawa
•
resistance standard 100 Ohm, 1000 Ohm with accuracy 0.005%
HP8903A Distortion analyzer and scope with bandwidth min. 20 MHz are recommended for THD measuring of
AC signals.
Configuration of the calibrator
Calibrator can be tested directly from the front panel terminals and without use of terminal adapter 140-01 or 140-
41. For built-in multimeter, testing cable adapters Option 40 and Option 60 are needed. To suppress influence of
noise or interference with power line frequency in measuring circuit it is recommended following setting of the
calibrator (in SETUP MENU):
•
Coil x50
OFF
•
GND U
ON (in capacitance test OFF)
•
GND I
ON (in capacitance test OFF)
Note:
It is recommended to ground only the voltage channel GND U ON, GND I OFF, for all ranges
except the generation of power or energy. If the meter to be calibrated has Lo terminal grounded,
it is recommended to un-ground both outputs of the calibrator, GND U OFF, GND I OFF to
exclude ground loops.
If it is grounded neither calibrator nor standard meter, higher level can occur on the output
terminals.
In general, when calibrator is connected to the standard meter, ground loops can be arise through
power line connection. Ground loops can result apparently worse noise, short term stability or
non-harmonic distortion of output signal. If necessary use toroidal chokes to suppress this
products.
•
Meter average
05
In all other items in SETUP MENU the setting of parameters don’t influence accuracy of the calibrator.
Use sin waveform of the output signal on all AC tests.
Performance verification may be performed after warm-up period i.e. 1 hour after switching on. Calibrator have
to be in temperature stabilize condition at minimum 8 hours before performance verification test is started.