Product Manual

Operation
14 900-0161-01-01 Rev B
Grid Tied
IMPORTANT:
Selling power to the utility company requires the authorization of the local electric jurisdiction.
How the utility company accommodates this will depend on their policies on the issue. Some
may pay for power sold; others may issue credit. Some policies may prohibit the use of this
mode altogether. Please check with the utility company and obtain their permission before
using this mode.
The
Grid Tied
mode allows the Radian inverter to become grid-interactive. This means that in
addition to using power from the utility grid for charging and loads, the inverter can also convert
excess battery power and sell it to the utility grid. Excess battery power usually comes from
renewable energy sources, such as PV arrays, hydroelectric turbines, and wind turbines.

The grid-interactive function uses
Offset
operation. See page 36 for more information.

The grid-interactive function utilizes the
Grid Support
settings. See page 37 for more information.
BENEFITS
:

Excess power is returned to the utility grid.
 The inverter will offset the loads with excess renewable energy if it is available from the batteries.
 If the excess energy is greater than the AC (load) demand, the excess will be sold to the grid.
NOTES
:

The inverter has a delay before selling will begin. This function, the
Re-Connect Delay Timer
, has a
default setting of five minutes. During this time, the inverter will not connect to the utility grid. The
timer is adjustable in the
Grid Interface Protection
menu (see below).

Upon initial connection to the utility grid, the inverter may be required to perform a battery charging
cycle. This may delay the operation of the grid-interactive function.

The grid-interactive function only operates when excess DC (renewable) power is available.

The grid-interactive function is not available in any of the other input modes.

Whenever energy produced from the renewable energy source exceeds the loads on the inverter
output, the system display will indicate selling. Any power not consumed by loads on the main panel
will be sold to the grid.

The amount of power an inverter can sell is not necessarily equal to its specified output wattage.
The
Maximum Sell Current
can be decreased if it is necessary to limit the power sold. This item is
available in the
Grid Interface Protection
menu (see next page). This setting is not affected by the
AC Limit
settings (see page 24).
 The amount of power sold is controlled by the utility grid voltage. The wattage sold equals this
voltage multiplied by the current. For example, if the inverter sells 30 amps and the voltage is
231 Vac, the inverter will sell 6.93 kVA. If the voltage is 242 Vac, the inverter will sell 7.26 kVA.
Additionally, output will vary with inverter temperature, battery type, and other conditions.
 This recommendation is specifically for the inverter’s grid-interactive function. In some cases, the
source may be sized larger to account for environmental conditions or the presence of DC loads.
This depends on individual site requirements.