Honeywell HVAC232 Series, Applications Manual

Page: 99 / 145

Application manual HVAC232/402 | Document 27-652 | Issue ENG06 | 2019-08-07 99
Overvoltage controller
0 = Disabled
1 = Enabled, Standard mode (Minor adjustments of OP frequency are made)
2 = Enabled, Shock load mode (Controller adjusts OP freq. up to max. freq.)
Undervoltage controller
0 = Disable
1 = Enable
These parameters allow the under-/overvoltage controllers to be switched
out of operation. This may be useful, for example, if the mains supply volt-
age varies more than –15% to +10% and the application will not tolerate
this over-/undervoltage. In this case, the regulator controls the output fre-
quency taking the supply fluctuations into account.
When a value other than 0 is selected also the Closed Loop overvoltage
controller becomes active (in Multi-Purpose Control application).
NOTE:
Over-/undervoltage trips may occur when controllers are
switched out of operation.
Efficiency optimization
Energy optimization, the frequency converter search for the minimum cur-
rent in order to save energy and lower motor noise.
0 = Disable
1 = Enable
I/f start enable
The I/f Start function is typically used with permanent magnet motors (PM)
to start the motor with constant current control. This is useful with high
power motors in which the resistance is low and the tuning of the U/f curve
difficult.
Applying the I/f Start function may also prove useful in providing sufficient
torque for the motor at start-up.
I/f Start Current
I/f Startfrequenz
Output Frequency
Motor Current
Time [s]
Fig. 45. I/f Start
I/f start frequency reference limit
Output frequency limit below which the defined I/f start current is fed to
motor.
I/f start current reference
The current fed to the motor when the I/f start function is activated.