Conext SW4048 4,000W 48V Installation

Grid-interactive and Other Features
975-0638-01-03 1–7
Time-of-Use Metering Utilities use time-of-use metering to set utility charges
during peak usage hours and to impose a surcharge. The Conext SW can be
configured (using the LoadShaveStart, LoadShaveStop and charger block [see
the Conext SW Owner’s Guide] settings) to overcome these peak charges by
using utility power to charge the battery bank during the inexpensive energy
hours and consuming the battery energy during expensive energy hours.
For example, if charger block is set between 9:00 AM and 10:00 PM and load
shaving is set between LoadShaveStart=6:00 PM and LoadShaveStop=9:00 PM,
charging on AC Input stops at 9:00 AM and the inverter continues to pass utility
AC through to the loads. If charging is required during the charger block period
then Conext SW can use an alternative external renewable energy source such
as an MPPT solar charge controller to charge the battery bank. The inverter
connects to the utility grid at 6:00 PM and supports running the loads using the
batteries. The inverter continues to run the loads until 9:00 PM.
The Conext SW then stops supporting the utility grid and passes utility AC
through to the loads at 9:01 PM. At the end of charger block at 10:00 PM utility
AC begins maintaining the batteries based on charger settings.
The above example allows an external renewable energy source to be utilized as
a primary charging source during a desired time window. The charger (using
utility power connected to AC Input) can then be used to supplement battery
charging when the utility rates are low.
When using the system for time-of-use metering, the system should be designed
with a battery capacity large enough to support loads during the entire peak rate
period without reaching the low battery cut out (Low Batt Cut Out) setting.
Load shaving can also be used with time-of-use metering and enhanced AC
support feature (see “Enhanced AC Support” on page 1–9 and “Enhanced AC
Support Setting” on page 4–31) to support self-consumption.
AC Support
AC Support is similar to load shaving because in both cases the Conext SW
inverter supplements AC current. However, unlike load shaving, AC Support
minimizes the AC input current to the Conext SW as long as the battery’s SOC
(state-of-charge) or battery voltage conditions allow it. AC Support allows the
Figure 1-2 Load Shaving in Action
Conext SW
Battery
Bank
SCP
AC Loads
AC OUTAC IN
DC
Grid or
Generator
NOTE: Current is regulated by placing a limit (Load Shave Amps) on the current
of the AC source.
15 A10 A
5 A