CT Lab Impedo DUO, Руководство пользователя

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Impedo DUO User Guide
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IEEE 802.3-2008 compliant Power over Ethernet (PoE) Plus is available on both
Ethernet ports at 30 to 60 V. The PoE capability enables the Impedo Duo to be
powered through the communication infrastructure. The Impedo Duo will therefore
be available at all times if the communication infrastructure stays active.
2.4.3 Voltage Inputs
Each individual meter contains 4 resistive differential voltage inputs made up of 6
terminals as shown in Figure 10 and Figure 11.
The first 4 terminals are used for 3 voltage inputs. V
1
, V
2
and V
3
are Neutral (V
com
)
referenced (V
1
-N, V
2
-N, V
3
-N) in a four wire Star connection (Figure 10) and
referenced to any one of the three phases in a 3 wire Delta connection (Figure 11).
Terminal 5 and 6 are used for the 4
th
(V
4+
, V
4-
) voltage input. It is a full differential
measurement normally used for Neutral to Earth measurement.
The voltage inputs terminals can accommodate conductors with sizes up to 2.5 mm
2
.
Figure 10 shows the voltage connections for a 3-phase 4-wire star system. Power is
calculated per phase and arithmetically added to obtain the 3-phase powers.
Figure 11 shows the voltage connections for a 3-phase 3-wire delta connection.
Three-phase power is calculated by the 2-watt meter method.
If voltages are connected in star (4-wire) on the terminals the
user can select star (4-wire) or delta (3-wire) topology in the
software.