Xantrex Technology 120 VAC/60 - Manual (Page 94)

OPERATION
Page
86
 2001 Xantrex Technology, Inc.
5916 - 195th Street N. E.
Arlington, WA 98223
Telephone: 360/435-8826
Fax: 360/435-2229
www.traceengineering.com
SW Series Inverter/Charger
Part No. 2031-5
Rev. C: February 2001
SELLING POWER - STORED IN THE BATTERIES
Power stored in the batteries can also be sold into the utility grid. This can be used together with the solar
array or alone without a solar array. The inverter can be programmed to sell the energy in the batteries at
a specific time and then to recharge the batteries at another time. Both the discharge level and discharge
rate can be adjusted to control the battery selling process.
Selling the power stored in the batteries can be used to level the output of the combined solar array and
battery system. This is beneficial during conditions of cloudy weather when the solar array output will vary
with each cloud that passes over. To set-up this ability, adjust the SET BATTERY SELL VOLTS DC menu
item under the BATTERY SELLING (17) menu heading for the maximum discharge voltage level
acceptable. The SET MAX SELL AMPS AC menu item should be set for the expected maximum output of
the solar array. Next, access the GRID USAGE TIMER (18) menu heading to allow setting of the time
period that the battery will be allowed to recharge during by adjusting the SET START CHARGE TIME and
SET END CHARGE TIME menu items. Outside of this time period, the inverter will sell the power stored in
the battery to the utility grid until the voltage reaches the BATTERY SELL VOLTS DC setting.
This mode can use the battery to maximize the output of the system during a specific period of time. An
example of these setting follows:
Figure 28, Selling Power Stored In The Batteries; Hypothetical Time Of Day Operational History
20:00 18:00
Begin Day
00:00
End Day
23:59
Set Start Bulk
time 20:00
End charge
time 08:00
Set Bulk Volts
DC 14.4
Bulk Volts
DC Setting
Max Sell
Amps Setting
Set Max Sell
amps 30
AC amps
Input
amps AC 00
{
{
Time
08:00
Set Absorption
time h: m 2:00
Max Charge
Amps Setting
Set Max Charge
amps AC 30
Absorption Time
Set Float
Volts DC 13.4
Float Volts
DC Setting
Charging from the
DC source (wind,
hydro or solar) has
started.
AC amps to grid (-)
AC amps from grid (+)
10:00
Set Battery Sell
Volts DC 12.4
Battery Sell Volts
DC Setting
LEGEND
Display/Settings
on Control Panel
Information
Set Float
Volts DC 13.4
DC Volts
Battery charging
from grid has
started
Start charge
time 18:00 Bulk charging
has started
POSITIVE (+) = Inverter is drawing power from grid.
NEGATIVE (-) = Inverter is selling power to grid.
Battery charging
from grid has
stopped