Woodward MRM4, Manual

Page: 276 / 460

Protective Elements
Parameter Description Setting range Default Menu path
LAT Timer Large motors with a high
inertia may experience
starting currents that
exceed the locked rotor
current and time. The
protective relay has logic
and provisions for a zero
speed switch input to
differentiate between a
stall and start condition.
If the motor is spinning
then the relay will not trip
on the normal locked
rotor time allowing the
motor to start.
Only available if: LAT Fc
= active.
1 - 1200s 1200s [Protection Para
/Global Prot Para
/MStart
/Start Control]
ABS Fc For certain applications,
such as pumping a fluid
up a pipe, the motor may
be driven backward for a
period of time after it
stops. The protective
relay provides an anti-
backspin timer to prevent
starting the motor while it
is spinning in the reverse
direction. The timer
begins counting from the
moment a stop is
declared by the relay. inactive,
active
inactive [Protection Para
/Global Prot Para
/MStart
/Start Control]
ABS Timer For certain applications,
such as pumping a fluid
up a pipe, the motor may
be driven backward for a
period of time after it
stops. The protective
relay provides an anti-
backspin timer to prevent
starting the motor while it
is spinning in the reverse
direction. The timer
begins counting from the
moment a stop is
declared by the relay.
Only available if: ABS Fc
= active.
1 - 3600s 3600s [Protection Para
/Global Prot Para
/MStart
/Start Control]
ZSS Zero Speed Switch inactive,
active
inactive [Protection Para
/Global Prot Para
/MStart
/Start Control]
Page 276 EN MRM4 01/11