Load Control; Time-Based Load Control - Kohler MPAC 1500 Manual

5.10 Load Control

The controller allows control of up to 9 separate loads.
Two load control modes allow selected loads to be
disconnected and reconnected to the source:
D
Time-based load control adds and removes loads
according to a timed sequence before and after
transfer.
D
Current-based load control adds or removes loads
according to the current measured through the
transfer switch. This mode allows load control based
on power usage.
The load control function is not activated if the controller
detects no available source.
Note that the load control can be set up to operate during
transfer to Source1 and/or Source2. Your application
may require load control during transfer to one source
(e.g. a generator set) but not the other source (e.g. the
utility).
Two types of load control are available: time-based load
control and current-based load control. Load Control
setup parameters are found in the Set Time Delays
menus.
Note: The load control setup parameters are found in
the Set S1 Time Delays and Set S2 Time Delays
menus.

5.10.1 Time-Based Load Control

The time-based load control function allows selected
loads to be disconnected from the source before
transfer and reconnected to the source after transfer at
different time intervals. The loads can be connected and
disconnected at different times for each source. The
pre-transfer signals are active only when both sources
are available.
When the load control function is activated, the contacts
open a programmed length of time before transfer to
allow controlled disconnection of selected loads. After
transfer, the contacts remain open for a programmed
length of time and then close to allow controlled
application of selected loads. For example, large motor
loads such as an air conditioner can be delayed to start
after other essential loads have been transferred.
The pre-transfer signals overlap the preferred-to-
standby and the standby-to-preferred time delays. See
Figure 5-11. The longer delay determines the time
delay before transfer.
TP-6714 4/10
Time-Based Load Control Setup
Setting up the load control function requires the
following steps:
1. Connect each selected load to an output terminal
on the main logic board or one of the input/output
modules. The high power module accessory is
available for high voltage or high current loads.
2. Use the Set Inputs/Outputs screen to assign the
connected output to one of the load control outputs
1--9. See Section 5.12.
3. Proceed to step 4 to set time-based load control for
source 1, if required. Skip to step 7 if time-based
load control is only needed for source 2 (standby
source).
4. In the Set S1 Time Delays menu, select Time as the
load control mode.
5. Enter the number of loads to control, which is equal
to the number of loads connected to outputs in
step 1.
6. Use the Set S1 Time Delays menu to set the
following associated time delays.
a. Load # Disc N>E:
disconnects loads a programmed time before
transfer from Normal to Emergency.
pre-transfer delays operate during loaded test,
loaded exercise, or programmed transfers for
peak shave operation when the transfer is
controlled.
b. Load # Rec E>N: post-transfer time delay
reconnects loads a programmed time after
transfer to Normal.
delay allows delayed or staggered addition of
selected loads to avoid starting numerous large
motors or other large loads at the same time.
Staggering the loads can minimize voltage dips
as large loads come online.
c. Loads to Add: Enter the number of loads that
have been connected to load control outputs for
pre-transfer
reconnect.
Repeat for source 2 if time-based load control is
required for source 2:
7. In the Set S2 Time Delays menu, select Time as the
load control mode.
pre-transfer time delay
The post-transfer time
disconnect and delayed
Section 5 Setup
The
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