7
= Key1
= Key 2
= Key 3
= Max. value or consumption = Min. value or supply
Functional description
Measurement
The electronical three phase measurement system
determines and digitalizes the effective values of
voltages and currents in 50/60 Hz networks.
Two random test measurements are carried out
each second on all current and voltage measuring
inputs. Signal interruptions, which are longer than
500ms are surely recognized. For each random test
two periods are scanned. The scanning frequency
for a 50Hz signal is 6400Hz. From those sampled
values the microprocessor calculates the electrical
magnitudes.
These measured values are indicated within the
programmable display. Highest values, lowest va-
lues and programming data can be saved in a
battery buffered storage.
Selected measured values will be saved with date
and time in a ring buffer.
Measurement in IT-networks
The UMG505 can be used in IT-networks with outer
conductor voltage up to 500V.
Measurement in networks without N
In networks without N, the voltages are measured
against an artificial neutral point (PE). From the
voltage L-PE, the voltage L-L is calculated.
The phase power in networks without N are used for
the calculation of the sum power only, but have no
further meaning.
Diagr.
Drawing
UMG505 in IT-networks with N.
2M
2M
2M
PE
UMG505
Voltage
measurement
Supply voltage
Impedance
Ground
2M
L2
L3
N
1n
1n
L1
Diagr.
Drawing
UMG505 in TN-networks.
2M
2M
2M
PE
UMG505
Voltage
measurement
Supply voltage
Ground
2M
L2
L3
N
1n
1n
L1
PE
500V 50/60Hz
230/400V 50/60Hz
Diagr.
Drawing
UMG505 in IT-networks without N.
2M
2M
2M
PE
UMG505
Voltage
measurement
Supply voltage
Impedance
Ground
2M
L1
L2
L3
1n
1n
500V 50/60Hz