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Universal Measuring Device UMG 500A
I
.. / 5A
Remaining time
By means of these keys, the remaining time in the present measuring period will be displayed in
seconds. After a measuring period has been elapsed, i.e. the remaining time has reached zero, a
new measuring period starts with the set value. By erasing the real work, the measuring period will also be
restarted.
%
.. / 5A
Measuring period
The measuring period to calculate mean real power can be read out by means of these keys. In
addition with the “+” and “-” key, the value can be set in steps of 1 second.
Setting range: 60 ... 9999 seconds.
P
min
Mean real power
By holding down the “P” key and operating the “min” key, the mean real power is displayed. To
differentiate this function from the display of the present value of real power, a decimal point
appears on the right of the quantity. The instrument accumulates work only by the consumed real power. The
mean value calculates mean power as follows:
Mean real power = accumulated work in present measuring period / remaining time of meas. period
Real power
This function displays the real power in the outer conductors or the sum of all three real powers is displayed.
The unit of measurement “kW” is indicated by an LED. With generator operation (power supply service),
the real power is displayed with three digits as “-###”. As an option, the instrument can display the real power
in MW to two decimal places.
P
U
I
Apparent power
This function shows the apparent power of the measured items. The unit is kVA; in this instance
it is indicated by the LEDs “V” and “A”. As an option, the instrument can display the apparent
power in MVA to two decimal places.
I
min
Mean Current
By holding down the “I” key and operating the “min” key, the mean current is displayed. To select
a measuring phase oder to erase the maximum value key “I” must be kept pressed. To differentiate
this function from the display of the present value of current, a decimal point appears on the right of the
quantity.
This function shows the mean value of the current over a period of 15 minutes. With the method for
generating the mean value used here, the mean value over the given time approaches to within 99.5% of the
present value.
U
Voltage
When this key is pressed, the device displays the effective value of the voltage to neutral or to the next phase
(L1-L2; L2-L3; L3-L1). The unit is indicated by the LED “V”. Instruments with the option “kV” display the
measurement value in the format ##.## kV. Instruments with the option “3-wire” only display voltage against
next phase.
Display range:
1 ... 9999 V
(standard)
0.01 ... 30.00 kV
(option “kV”)
0.01 ... 99.99 kV
(option “kV” + option “3-wire”)
I
Current
This function displays the effective value of the current in the selected current path. The LED “A” indicates
the unit of measurement.
