Eaton SmartWire-DT SWD Series User Manual

4 PKE-SWD-32, interface for motor-starter combination with PKE PKE12/32
4.9 Programming
SmartWire-DT module IP20 01/20 MN05006001Z-EN www.eaton.com 113
The message 0x3 “phase failure/phase unbalance” is set if there is a phase
current difference of 50% between the highest phase current measured and
phase affected. This message is reset if the phase current difference is
below 25 %.
The “phase failure/phase unbalance” does not force the interruption of the
main circuits. To protect the connected motor in the event of phase loss/
phase unbalance, the tripping time in the event of an overcurrent is reduced
to 40 % compared to when the phase load is symmetrical. The interruption
of the main circuits is executed early if the thermal motor image reaches 100
%.
4.9.1.6 Motor current [%] (I-REL)
The PKE-SWD-32 indicates the actual motor current via the input byte 2.
The motor current is shown as a relative value in the ranges 0 % (0x00) to
255 % (0xFF). The transferred relative value is calculated from the value of
the highest phase current measured in relation to the set current value of the
overload release.
The accuracy of the relative current indication depends on the measured
phase current in relation to the current range of the PKE trip block. In order to
measure the phase current with sufficient accuracy, a phase current of at
least 85% of the minimum mark of the variable overload release on the PKE
trip block (e.g. trip block PKE-XTUA-4 ￫ I
min
= 0.8 x 1 A = 0.8 A) must be
present.
The maximum measuring accuracy of the transferred relative current value is
5%.
4.9.1.7 Thermal motor image [TH]
Depending on the current range and the actual current flow, the PKE motor-
protective circuit-breaker calculates the thermal state of the motor and pro-
vides it as a data byte. The thermal load of the motor is mapped via input
byte 3. The value is displayed as a relative value in the ranges 0 % (0x00) to
255 % (0xFF).
The main circuits are interrupted as a result of a motor overload if the thermal
motor model is 110%. In the event of phase failure or phase unbalance, the
main circuits are interrupted at a value of 100 % of the thermal motor image.
In the event of a phase unbalance and trip caused by an overload, the value
of the thermal motor image is raised from 100 % to 110 %.
￫
The Test position on the PKE trip block then causes a test trip if
at least one phase current of 60 % of the minimum mark of the
variable overload release on the PKE trip block flows via all three
main circuits.
￫
The value of the thermal motor image can likewise be read as
an acyclical object (￫ Section 4.9.4, "Acyclic data", page 121).

Eaton SmartWire-DT SWD Series Specifications

General

Brand	Eaton
Model	SmartWire-DT SWD Series
Category	Control Unit
Language	English