Motor Protection By Means Of The Switch; Motor Thermal Model - ABB DCS 500B Description

Motor Protection
by means of the
switch

Motor thermal model

DCS 500 Software Description
Note:
HIGH VALUE and LOW VALUE parameters in AI function blocks
are not in use when AI output is defined in °C or in ohms (Ω).
Jumper settings of SDCS-IOB3-card are made such that the input
voltage range in both channels is +/-10V.
DC-motor temperature protection can also be supervised by means
of the temperature switch in the DC-motor. The contact of the
switch opens in a certain temperature. The connection to the soft-
ware is by means of the digital input,and the input signal [KLIXON
IN] (1404) is used in software. When the input state changes from 1
to 0, the overtemperature trip will be activated.
HW SW
SDCS-
DIxx
IOx-x
M
O1
O2
T20
Figure 48 Overtemperature protection by means of the thermal
switch.
The DC-motor must be always protected against overtemperature.
If a direct temperature measurement of the motor is not available,
the thermal model of the motor can be used when the current limits
of the drive are set higher than the nominal motor current.
In the DCS500B there are two thermal models available that can be
used at the same time. By means of input signal [MOTOR2] (913)
the measured armature current is directed to the correct model.
Functional Software description
SP
MOTOR 1 PROTECTION
1401
[TEMP IN]
1402
TEMP ALARM L
C:
1403
107xx
C: TEMP FAULT L
107xx 1404
[KLIXON IN]
1405
C: MODEL1.SEL
1406
MODEL1.CURR
C:
1407
C: MODEL1.ALARM L
1408
C: MODEL1.TRIP L
1409
C: MODEL1.TC
T20
11402
MOT1 CALC TEMP
69