
284 Electric Motors and Drives
POWER RANGE FOR MOTORS AND DRIVES
The diagram (Figure 10.1) gives a broad indication of the
power range for the most common types of motor and drive.
There is of course no sharp cut-off point in most cases, and
this is reflected in the use of dotted lines at the top and
bottom of each range. We should also bear in mind that we
are talking here about the continuously rated maximum
power at the normal base speed, and as we have seen most
motors will be able to exceed this for short periods.
Maximum speed and speed range
We saw in Chapter
1
that as a general rule, for a given power
the higher the base speed the smalle ...