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80994B_MHW_GTF-Xtra_05-2016_ENG
Phase angle (PA)
This mode controls power on the load via modulation of trigger angle
q
Example:
if power to be transferred to the load is 100%,
q
= 180° or if power to be transferred to the load is 50%,
q
= 90°
Figure 23
Resistive
load
Inductive
load
ADDITIONAL FUNCTIONS
Softstart
This type of start can be enabled either in phase control or pulse train mode and in zero-crossing mode (ZC, BF, HSC).
In phase control, the increment of conduction angle q stops at the corresponding value of the power to be transferred to
the load.
Control of maximum peak current (useful in case of short circuit on the load or of loads with high temperature coefficients
to automatically adjust start time to the load) can be enabled during softstart. When the load shut-off time (settable) is
exceeded, the ramp is reactivated at the next power-on.
Figure 24
Example of firing ramp with phase Soft-Start
