Speed Acceleration - GE 869 Instruction Manual

CHAPTER 4: SETPOINTS

2-Speed Acceleration

NOTE:
869 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL
VD STALL TIME @ 100% V
Range: 0.1 to 1000.0 in steps of 0.1
Default: 10.0 s
VD ACCEL. INTERSECT @ 100% V
Range: 1.50 to 20.00 in steps of 0.01
Default: 5.00 x FLA
Figure 4-61: Speed2 Thermal Model logic diagram
Path:
Setpoints > Protection > Group1(6) > 2-Speed Motor > Speed2 Acceleration
Speed2 Acceleration Time functionality is enabled when the motor is switched from speed
1 to speed 2 and 2-Speed Motor Protection (set under Setpoints/System/Motor/Setup) is
enabled.
Speed2 Acceleration Current and Mode settings and functionality at speed 2 are identical
to those of speed 1 and are described in the Acceleration Time element.
Two additional setting define the transition between speeds. A two-speed motor is usually
started at a low speed (speed 1) and then switched to a higher speed (speed 2) when
required. When the motor starts directly at high speed, then the Speed2 Max. Accel. Time
setting (defined under Setup>Motor) specifies the maximum acceleration time at speed 2.
When the motor is switched from a low-to-high speed setting, the speed 2 Accel Time Fr.
Spd 1-2 setting specifies the acceleration time. When the motor is switched from high
speed to low speed, the Speed2 Trans 2-1 Op FlexLogic operand is set for a time defined
by the Speed2 Switch 2-1 Delay setting (under Setpoints/System/Motor/Setup) to allow
inputs for control logic of contactors and breakers at both speeds. The acceleration time at
speed 2 becomes functional only if the acceleration time at speed 1 is enabled. When the
acceleration time at any speed is not required, it can be permanently blocked.
CURRENT
Range: 1.00 to 10.00 x FLA in steps of 0.01
Default: 6.00 x FLA
MODE
Range: Definite Time, Adaptive
Default: Definite Time
PROTECTION
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