GE M60 UR Series

GE Multilin M60 Motor Protection System 5-141
5 SETTINGS 5.6 GROUPED ELEMENTS
5
5.6.3 MOTOR
a) MAIN MENU
PATH: SETTINGS  GROUPED ELEMENTS  SETTING GROUP 1(6)  MOTOR
b) ACCELERATION TIME
PATH: SETTINGS  GROUPED ELEMENTS  SETTING GROUP 1(6)  MOTOR  ACCELERATION TIME
Many motors have quite a time margin between acceleration-time and the stall limit. It is advantageous to detect stalling
during a start as early as possible to minimize re-starting delays once the cause of the stall is remedied, e.g. neglecting to
release a fan brake.
The acceleration time element compares actual starting time with a pre-determined time setting and operates when it is
exceeded. This element has the functionality to adapt the tripping time for starts with lower starting current, and it stores
acceleration time and current of the last five starts. The element uses currents configured under
SYSTEM SETUP  MOTOR
 MOTOR LINE SOURCE and motor status asserted by the thermal model element. Both the signal source and thermal pro-
tection must be configured properly in order for the acceleration time protection to operate.
The figure below shows examples of constant and variable acceleration currents and explains measurement of the acceler-
ation time and current. Part A represents a constant current start and part B represents a variable current start.
 MOTOR

 ACCELERATION
 TIME
See page 5-141.
MESSAGE
 THERMAL MODEL

See page 5-143.
MESSAGE
 AMP UNBALANCE 1

See page 5-163.
MESSAGE
 AMP UNBALANCE 2

See page 5-163.
MESSAGE
 UNDERCURRENT

See page 5-165.
MESSAGE
 MECHANICAL JAM

See page 5-164.
MESSAGE
 TWO-SPEED MOTOR

See page 5-167.
 ACCELERATION TIME

ACCELERATION
FUNCTION: Disabled
Range: Disabled, Enabled
MESSAGE
ACCELERATION
CURRENT: 6.00 x FLC
Range: 1.00 to 10.00 x FLC in steps of 0.01
MESSAGE
ACCELERATION TIME:
10.00 s
Range: 0.50 to 180.00 s in steps of 0.01
MESSAGE
ACCELERATION MODE:
Definite Time
Range: Definite Time, Adaptive
MESSAGE
ACCELERATION BLOCK:
Off
Range: FlexLogic™ operand
MESSAGE
ACCLERATION TARGET:
Self-reset
Range: Self-reset, Latched, Disabled
MESSAGE
ACCLERATION EVENTS:
Disabled
Range: Disabled, Enabled