Honeywell SmartVFD HVAC MR4 User Manual page 106

HVAC A
PPLICATION
3.5.3.2 Motor Control Settings
Code Parameter
M3.1.2.1 Switching frequency
M3.1.2.3 Motor preheat function
Motor preheat temper-
M3.1.2.4
ature limit
M3.1.2.5 Motor preheat current
Min Max Unit
1.5 Varies
0 3
-20 80
0.5*I L
0
Table 23. Advanced motor settings
Default ID
kHz Varies 601
0 1225
°C 0 1226
A Varies 1227
Honeywell
• 34
Description
Motor noise can be mini-
mised using a high switch-
ing frequency. Increasing
the switching frequency
reduces the capacity of the
drive. It is recommended to
use a lower frequency when
the motor cable is long in
order to minimize capaci-
tive currents in the cable.
0 = Not used
1 = Always in stop state
2 = Controlled by DI
3 = Temperature limit (heat-
sink)
NOTE:
Virtual digital input
can be activated by RTC
Motor preheat is switched
on when the heatsink tem-
perature goes below this
level (if par. M3.1.2.3 is set
Temperature limit
to .
If limit is e.g. 10°C feeding
current starts at 10 °C and
stops at 11°C (1-degree
hysteresis).
DC current for pre-heating
of motor and drive in stop
state. Activated by digital
input or by temperature
limit.