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Gary:<br><br>
I think you are a little confused about the operating modes of the XW
inverter:<br><br>
In the AC Passthru mode, no battery charging occurs. Below is the
passage from the manual that describes this:<br><br>
<i>The AC connected to the AC1 or AC2 input is passing directly through
the Xantrex XW<br>
Series Inverter/Charger to the loads. The batteries are not being charged
in this state.<br><br>
</i>In the normal transfer mode, battery charging does occur. It is
my clear understanding that the Xantrex SW and XW inverters and the
Outback FX and Radian inverters will regulate battery charging so that
the charger circuit uses only excess amperage available. For
example: If the input breaker size is programmed for 60 amps and
there is 60 amps of load, 0 amps of AC will be used for battery
charging. If the load decreases to 50 amps, 10 amps of AC will be
used for battery charging, etc.. Therefore, the OCPD does
<u>not</u> need to be sized to accommodate both uses of input
AC.<br><br>
Below is a passage from the XW Operating Manual that describes
this:<br><br>
<i>In addition, the battery charger can reduce its charging current to
the batteries<br>
so the combined charge AC current and total load current does not exceed
the<br>
capacity of the generator or trip its output breakers or fuses.<br><br>
</i>Extending this discussion beyond the current topic (pun intended), we
need to understand what happens if the connected loads exceed the input
breaker rating. Here the game changes. The FX inverter can
not prevent the overload from passing to the input breaker, possibly
tripping it. The SW, XW and Radian inverters can provide
"Generator Support." Do not confuse Generator Support
with Generator Remote start functions. Generator Support allows the
inverter to sync to, and assist the AC input source in powering
loads. To use the example above: If the load rises to 70
amps, the inverter draws energy from the batteries to provide the last 10
amps. <br><br>
Below is the passage from the XW manual that describes this:<br><br>
<i>AC2 Breaker: Sets the AC2 (Gen) breaker size, based on the size
of the installed AC breaker. The<br>
breaker size must not exceed the capacity of the generator. The Xantrex
XW Series<br>
Inverter/Charger limits the maximum input current to this setting by
derating its charging<br>
current to an equivalent of 80% of the AC breaker size. If the connected
loads exceed the<br>
AC2 breaker setting, the AC breaker trips. The breaker may not trip if
Gen Support is<br>
enabled and Gen Amps is configured not to exceed the generator\u2019s rated
output current.<br><br>
</i>I hope this information is relevant, correct and helpful.<br><br>
Sincerely,<br><br>
William Miller<br><br>
<br><br>
<br>
At 08:24 AM 3/1/2013, you wrote:<br>
<blockquote type=cite class=cite cite>Larry:<br><br>
In the case of the Xantrex XW Series, while in the "AC
Pass-Thru" Mode, the internal transfer switch relay connects the
protected loads directly to the AC1 grid input. The XW internal battery
charger is then activated to recharge the battery bank.<br><br>
The OCPD(s) through which the protected load amps and charging amps are
passing must be sized to accommodate both at the same time.<br><br>
Regards,<br><br>
Gary Willett<br>
Icarus Solar</blockquote></body>
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