Gossen MetraWatt METRAHIT T-COM PLUS, Operating Instructions Manual

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20 GMC-I Messtechnik GmbH
Control Functions
➭
Briefly press the ZERO | ESC key.
The instrument acknowledges storage of the reference value
with an acoustic signal, and the “ZERO

REL” or the “

REL”
symbol appears at the LCD. The value measured at the
moment the key is pressed serves as a reference value.
➭
The reference value can be cleared by once again pressing the
ZERO | ESC key.
Notes Regarding Relative Measurement
• Relative measurement effects the digital display only. The
analog display continues to read out the original measured value.
• In the case of relative measurement,

F or AC quantities may
also appear as negative values.
4.3 Display (LCD)
4.3.1 Digital Display
Measured Value, Unit of Measure, Type of Current, Polarity
The measured value with decimal and plus or minus sign appears
at the digital display. The selected unit of measure and current
type are displayed as well. A minus sign appears to the left of the
value during the measurement of zero-frequency quantities, if the
plus pole of the measured quantity is applied to the “

” input.
The “
0
.
d iSP
” parameter can be used to determine whether lead-
ing zeros will be appear or be suppressed at the measured value
display (see chapter 7.4).
Overranging
If the upper range limit of 3100 digits is exceeded “
0L
” (overload)
appears at the display.
Exceptions: “
0L
” appears at the display as of 610.0 V in the case
of voltage measurement in the 600 V range, as of 5100 digits for
diode testing, and as of 1100 digits in the 1 A range.
4.3.2 Analog Display
Measured Value, Polarity
The analog display demonstrates the dynamic performance of a
moving-coil mechanism. This display is especially advantageous
for observing measured value fluctuation, and for balancing
procedures.
Two different display modes can be selected in the “
SETUP
” menu
with the help of the “
A
.
d iSP
” parameter (see chapter 7.4):
• Bar graph
• Pointer: the current measured value is tracked in real-time
The analog scale displays a negative range of 5 scale divisions for
the measurement of zero-frequency quantities, allowing for
precise observation of measured value fluctuation around zero. If
the measured value exceeds the negative range of 5 scale
divisions, polarity is reversed at the analog display.
Scaling of the analog scale is automatic. This is very helpful for
manual measuring range selection.
Overranging
Overranging in the positive range is displayed by means of the
right triangle symbol.
Refresh Rate
In the bar graph and pointer modes, the analog display is
refreshed 40 times per second.