Conext XW+ 6848 NA Owner's Manual page 79

Fixed Battery Voltage
Battery
Voltage
[Grid Supp Volts]+2V
[Grid Supp Volts]
Figure 3-8 Grid-tie Sell Mode
975-0240-01-01
Prioritizing and Managing Energy Sources with Advanced Features
Enhanced Grid Support with Conext MPPT Solar Charge Controllers This
setup is suitable for Conext Systems with only Conext MPPT Solar Charge
Controller(s) networked to Conext XW+ units through Xanbus. In this
configuration, Grid Supp Volts is set above the charge controller's Equalization
voltage (for example, 64 volts).
In an enhanced grid support set up the Conext XW+ automatically tracks the
Conext MPPT Solar Charge Controller voltage as it transitions through charge
states (from bulk to absorption to float). This allows the system to execute a
complete battery charge cycle while still converting excess DC power to AC
power to support the AC loads or be exported to the utility grid. In doing so, the
Conext XW+ only uses excess DC not required by the battery or used to support
local AC loads and sells it to the grid, thereby maximizing the use of the PV array.
Since this set up allows the battery bank voltage to reach absorption levels
(when PV harvest is adequate), the state of health of the battery is improved. The
sell entry and regulation voltage level is 1 V below absorption and float of the
Conext Solar Charge Controller set points. The exit from sell is 1.5 V below
absorption and float of the Conext Solar Charge Controller set points.
Fast Re-Entry Sell Mode: no [Tdelay]
Battery Voltage Regulation
Re-Entry Sell Mode +[Tdelay]
Exit Sell Mode +[Tdelay]
Advanced/Adv Features config:
[Tdelay]= 20 sec default
[Tdelay]=Enable: 40 sec
Vbat>GSV
[entry]
Note:
[Tdelay] is an entry/exit transition time delay to/from grid support and sell mode.
If the battery voltage has higher fluctuations due to DC renewable sources
(e.g. charge controllers, wind turbines, and so on), then the time delay can be
increased by setting Sell Dly 40s to enabled (Table 3-12, "Advanced Features
Menu" on page 3–49).
If the battery voltage has a sudden increase change greater than Grid Support
Volts + 2 V, then the Conext XW+ will override the delay and enter grid support
or sell mode immediately.
Vbat<GSV
[exit]
Enhanced Interactive Mode
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