UNIPOWER
UP-2210R/P Hardware installation and configuration manual
37
4.6.3
Isolated (ungrounded) 3-wire systems
Typical examples: Industrial MV networks.
In a 3-phase, 3-wire network without neutral conductor it is also common to isolate the network and
leave it ungrounded.
Connect your UP-2210 to measure
line-line voltages U1-U3
and phase currents
I1-I3
according to
one of the sections 4.4.9, 4.4.10, 4.4.11 and 4.4.12 depending on how many PT/CT there are.
Channels
U4
and
I4
are normally not used. Connect them to ground.
4.6.4
Low voltage 4- or 5-wire systems
In a 4-wire network with neutral conductor or 5-wire network with neutral and ground connectors
phase (line-neutral) voltages should be measured.
Connect your UP-2210 to measure
line-neutral voltages U1-U3
and phase currents
I1-I3
according
to section 4.4.8.
Connect channel
I4
to measure the neutral current.
Channel
U4
could be used to measure the voltage between neutral and ground. If it is not used,
connect it to ground.
4.6.5
Alternative connection option for MV/HV 3-wire systems
From a
Power Quality point of view
line-to-line
voltages should always be measured (see sections
4.6.1, 4.6.2 and 4.6.3). This is in accordance with existing Power Quality standards like EN 50160.
As an alternative, from a disturbance point of view, you could choose to measure
line-to-ground
voltages instead. With this configuration you can see earth faults per phase. This configuration is
mainly a tool for analysing disturbances.
Connect your UP-2210 to measure
line-to-neutral voltages
U1-U3 and phase currents I1-I3
according to section 4.4.8.
If the system is impedance grounded, connect channel
U4
to measure the transformer neutral point
voltage U
n
.
Channel
I4
is normally not used. Connect it to ground.
4.7
Digital inputs and outputs
The UP-2210R can be equipped with 16 digital inputs and 3 relay outputs. They can be used to
record external events to the PQ Secure system or send signals to other equipment in case of a sag/
swell or transient. These inputs/outputs are used in a similar way if the meter is used as a fault
recorder. The configuration of the digital inputs/outputs is made via the PQ Online program. For
more information about this, please see the “
PQ Secure SQL User and software installation manual
”.
These functions are optional modules.
