Group 20: Limits - ABB ACS550 User Manual

ACS550 User's Manual

Group 20: LIMITS

This group defines minimum and maximum limits to follow in driving the motor –
speed, frequency, current, torque, etc.
Code Description
2001 MINIMUM SPEED
Defines the minimum speed (rpm) allowed.
• A positive (or zero) minimum speed value defines two ranges,
one positive and one negative.
• A negative minimum speed value defines one speed range.
• See the figure.
2002 MAXIMUM SPEED
Defines the maximum speed (rpm) allowed.
2003 MAX CURRENT
Defines the maximum output current (A) supplied by the drive to the motor.
2005 OVERVOLT CTRL
Sets the DC overvoltage controller on or off.
• Fast braking of a high inertia load causes the DC bus voltage to rise to the overvoltage control limit. To prevent the
DC voltage from exceeding the trip limit, the overvoltage controller automatically decreases the braking torque by
increasing output frequency.
0 = – Disables controller.
DISABLE
1 = – Enables controller
ENABLE
Note: If a braking chopper or a braking resistor is connected to the drive, this parameter value must be set to
0 ( ) to ensure proper operation of the chopper.
DISABLE
2006 UNDERVOLT CTRL
Sets the DC undervoltage controller on or off. When on:
• If the DC bus voltage drops due to loss of input power, the undervoltage controller decreases the motor speed in
order to keep the DC bus voltage above the lower limit.
• When the motor speed decreases, the inertia of the load causes regeneration back into the drive, keeping the DC
bus charged and preventing an undervoltage trip.
• The DC undervoltage controller increases power loss ride-through on systems with a high inertia, such as a
centrifuge or a fan.
0 = – Disables controller.
DISABLE
1 = ( ) – Enables controller with 500 ms time limit for operation.
ENABLE TIME
2 = – Enables controller without maximum time limit for operation.
ENABLE
Speed
2001 value is < 0
P 2002
Speed range allowed
0
P 2001
2001 value is > 0
Speed
P 2002
Speed range allowed
P 2001
0
-(P 2001)
Speed range allowed
-(P 2002)
125
Time
Time
Parameters