Source Setup; Phase Rotation; In-Phase Monitor; Preferred Source Selection - Kohler MPAC 1500 Manual

5.11 Source Setup

5.11.1 Phase Rotation

The Phase Rotation menu appears only if a three-phase
source is selected. (See Set Number of Phases later in
the Set Sources menus for the Normal and Emergency
sources.)
Select ABC, BAC, or disabled. Phase rotation can be
disabled for programmed-transition
standard-transition models in applications that do not
have phase-sensitive loads. Phase rotation cannot be
disabled on closed-transition models.

5.11.2 In-Phase Monitor

Standard-Transition Models
The in-phase monitor can be enabled or disabled for
standard-transition models.
operates prior to transfer when both sources are
available. Transfer is inhibited while both sources are
greater than 2 cycles apart. If the connected source falls
below 70% of its nominal voltage rating, the in-phase
monitor terminates and allows transfer.
The synchronism window has a default value of 5_ and
is adjustable from 15_ to 5_ before synchronism only.
The in-phase monitor feature can be enabled for
Util-Gen and Gen-Gen modes of operation. In Util-Util
mode, it is assumed that both sources are always in
phase with each other, and immediate transfer occurs
when in-phase monitoring is enabled.
Programmed-Transition Models
The in-phase monitor is disabled for programmed-
transition models.
Closed-Transition Models
The in-phase monitor is always enabled for closed-
transition models. Synchronization settings for closed-
transition models include voltage differential, frequency
differential, angle differential, and the Fail to Sync time
delay. Transfer is inhibited when any of the differential
readings between the two sources are outside the set
limits. See Figure 5-13.
TP-6714 4/10
models or
The in-phase monitor
Adjustment
Range
Parameter
Voltage
0--5%
Differential
Frequency
0--0.3 Hz
Differential
Angle
0--10 degrees
Differential
Fail to Sync
0--60 min.
time delay
Figure 5-13 Synchronization Settings for Closed-
Transition Switches

5.11.3 Preferred Source Selection

The preferred source selection function allows selection
of either Source N or Source E as the preferred source.
Note: The alarm module accessory must be installed
for this function to operate. See Section 8.5.
The transfer switch seeks and transfers to the preferred
source whenever it is available. Source N is always the
source connected to the Normal side of the transfer
switch, and Source E is always connected to the
Emergency side. Generator engine start relays are
assigned to the source (Source N or Source E). The
engine start relays do not change when the preferred
source selection changes. This prevents the need to
change the wiring of the engine start relay(s) when the
preferred source changes.
Source Types. The transfer switch is factory-set for the
utility-generator set source types. This type uses one
generator set, which is connected to the Emergency
side of the contactor (Source E), and one engine start
relay. The engine start contact is assigned to the
connected generator set and does not change
assignment when the preferred source selection is
changed. In this mode, if the preferred source selection
is set to Source E, the system operates the generator set
indefinitely, transferring to utility power only if the
generator set fails.
Default Setting
5%
0.1 Hz
10 degrees
30 sec.
Section 5 Setup 73