CTV-PRB004-EN
35
Medium-Voltage Starter Types (2,300–6,600 Volts)
Medium Voltage—Primary Reactor (2.3–6.6 kV)
Primary Reactor Starter (2,300–6,600 volts)
One of the most common starters in the industry is the primary reactor. To illustrate a typical
starting sequence using a generic (non-Trane) schematic, refer to
Figure 27, p. 36
and the starting
sequence below.
Starting sequence
1. A “start” signal from the chiller controller energizes the pilot relay (PR).
2. The PR contacts close to energize the start contactor (1M).
3. The 1M contacts close to connect the compressor motor to the line with the motor in series with
the reactor.
4. A time delay or current monitoring device initiates transition by energizing the run contactor
(2M).
Figure 26. Unit-mounted, across-the-line, medium-voltage starter
1. Top-entry power
connection
2. Current-limited
power fuses
3. Vacuum
contactors
4. Low-voltage
section
5. Isolation switch
(provision for one
lock)
6. Control-power
transformer
1
2
3
4
6
5
CTV-PRB004.book Page 35 Sunday, December 18, 2011 6:39 PM
