GE MI-869 User Manual

4–166 869 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL
PROTECTION CHAPTER 4: SETPOINTS
2-Speed Motor
The two-speed motor feature provides proper protection for a two-speed motor where
there are two different full load values. If the two-speed motor feature is used, setpoint
2-
Speed Motor Protection
must be set to Enabled under Setpoints > System > Motor > Setup .
Also, assignable input for setpoint
Speed2 Motor Switch under Setpoints > System > Motor
> Setup must monitor for a contact closure. Contact closure signifies that the motor is in
Speed 2; if the input is open, it signifies that the motor is in Speed 1. This allows the 869 to
det
ermine which settings must be active at any given point in time.
Speed2 Thermal
Model
Path: Setpoints > Protection > Group1(6) > 2-Speed Motor > Speed2 Thermal Model
When the two-speed motor functionality is used, these settings allow the selection of the
proper parameters for the thermal model when the motor is switched to the second speed.
There is one thermal model in the 869, and it has inputs for overload conditions from
calculations at both speeds. As such, the accumulated thermal capacity is calculated from
overload contributions at each speed.
The algorithm integrates the heating at each spee
d into one thermal model using a
common thermal capacity used register value for both speeds.
Refer to the Thermal model sub-section for details on settings for thermal model at the
second mot
or speed.
OVERLOAD CURVE
Ra
nge: Motor, Flexcurve A, Flexcurve B, Flexcurve C, Flexcurve D, IEC
Default: Motor
TD MULTIPLIER
Range: 1.00 to 25.00 in steps of 0.01 when thermal model curve is Motor
Default: 1.00
Range: 0.00 to 600.00 in steps of 0.01 when thermal model curve is Flexcurve
Default: 0.00
VOLT. DEPENDENT (VD) FUNCTION
Range: Disabled, Enabled
Default: Disabled
VD MIN MOTOR VOLTS
Range: 60 to 99% in steps of 1
Default: 80%
VD VOLTAGE LOSS
Range: Off, any FlexLogic operand
Default: Off
VD STALL CURRENT @ MIN V
Range: 1.50 to 20.00 FLA in steps of 0.01
Default: 4.50 x FLA
VD STALL TIME @ MIN V
Range: 0.1 to 1000.0 in steps of 0.1
Default: 20.0 s
VD ACCEL. INTERSECT @ MIN V
Range: 1.50 to 20.00 in steps of 0.01
Default: 4.00 x FLA
VD STALL CURRENT @ 100% V
Range: 1.50 to 20.00 FLA in steps of 0.01
Default: 6.00 x FLA

GE MI-869 Specifications

General

Brand	GE
Model	MI-869
Category	Protection Device
Language	English