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Figure 5.11:
Changing Fan 1 speed command for Example 2
5.1.2
Fan Current, DC Bus Voltage, and Temperature alarm
limits
The Fan VFDs have settings for alarm limits for the output current, dc bus voltage, and
temperature of the VFD. All of them function in the same way, they just have different
units, so we will just look at one of them and then the reader can apply it to the rest of
them
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.
Consider the output current settings, in amps (A), shown in Figure 5.12. There are
two sets of grey input boxes, one set on the right side, one on the left.
Figure 5.12:
Setting output current (A) limits for Fan 1
The grey input boxes to the right are used to indicate the full range of values the
output current, in amps can take on. The boxes on the left are used to set values for the
lower and upper alarm values, if needed. For example, if the VFD drive should output a
maximum of 15 amps during steady state operation, and the customer wished the screen
to have an indicator showing that it has exceeded 12 amps so they know it is starting
to overamp, then the following would be the way the screen would be set up if no lower
alarm is used and the lower limit is zero amps.
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for further help see Oliver’s training video ”Setting up the Fan VFDs”
