SSD 605C, Руководство по эксплуатации продукта

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Application Notes
13-5
605C Frequency Inverter
High Starting Torque
Applications requiring high motor starting torque (greater than 100% of rated torque) need
careful setup of the drive voltage boost feature. For most motors, a FIXED BOOST parameter
(FLUXING function block) setting of 6.0% is usually adequate. Setting the FIXED BOOST
parameter level too high can cause the drive current limit feature to operate. If this occurs, the
drive will be unable to ramp up in frequency. The LIMITING diagnostic (CURRENT LIMIT
function block) will indicate TRUE when the current limit feature is operating. Simply reducing
the level of the FIXED BOOST parameter will remove this problem. It is important to use the
minimum level of FIXED BOOST necessary to accelerate the load. Using a level of FIXED
BOOST higher than necessary will lead to increased motor heating and increased risk of drive
overload.
Note: Motor torques greater than 100% require high currents to be drawn from the drive. Thus,
the
MOTOR I LIMIT
parameter (CURRENT LIMIT function block) will have to be set
accordingly such that the drive current limit feature will not activate when accelerating the
load.
The best motor starting performance can be achieved by setting up the SLIP COMP function
block, refer to Chapter 6: SLIP COMP. Also setting the BASE VOLTS parameter (VOLTAGE
CONTROL function block) to 115.4% and the SWITCHING FREQ parameter (PATTERN
GEN function block) to 3kHz, can help to start difficult loads in the most extreme cases.