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Wrenches:<br>
Followup on my earlier post about the XP125: Dan at Exeltech has
stepped up in a major way. Here are a few quoted excerpts from a set
of emails he has sent me about this:<br>
<br>
<b>1. Cause and solution:</b><br>
Certain of the new electronic chargers (such as De Walt, Craftsman
(usually made by De Walt, etc. and branded "Craftsman"), and others
are highly capacitive on their input. In certain instances, this
can drive our voltage control loop unstable in the smallest
inverters. Anything that looks larger than approximately 1
microfarad might do this - but again .. only for our *smallest*
inverters, such as the XP125 and XP250. Our larger inverters
(>600W) and our new designs do not exhibit this sensitivity.<br>
<br>
If any of our inverters are going to be used with a capacitive load,
let us know and we will provide free of charge a component for to
you to wire in series with the inverter AC output that will
counteract the effects of a capacitive load.<br>
<br>
Also .. since a capacitive load appears to be the situation with
your customer, please contact me at the office on Monday and I will
authorize the repair of her unit free of charge. We will also
include the component (referenced above) for connection in series
with the inverter when you re-install it.<br>
<font color="#000000"><b><br>
2. What the fix is, and why it's done this way:</b><br>
</font>
<div dir="ltr" align="left"><font color="#000000"><big><font
face="Times New Roman, Times, serif"><span
class="545082022-13092011"><font size="2"><big>In the case
of the XP125 (sorry, no pun intended), there's not
sufficient room inside the unit to add the inductor -
hence external mounting and connection (anywhere you
like). You could install it into the "line" lead of a
power strip and it will do the job perfectly. Also ..
there's an issue if we modify anything internal to the
inverter. It's UL Listed .. and if we even change the
paint color .. UL gets involved. If *we* install the
inductor .. it affects our UL Listing. If *you*
install the inductor .. UL doesn't care.</big></font></span></font></big></font></div>
<div dir="ltr" align="left"><font color="#000000"><big><font
face="Times New Roman, Times, serif"><span
class="545082022-13092011"></span> </font></big></font></div>
<div dir="ltr" align="left"><font color="#000000"><big><font
face="Times New Roman, Times, serif"><span
class="545082022-13092011"><font size="2"><big>#2: The
inductor can be installed in the circuit used for any
and all loads. No need to have it carry the power for
just the charger. Install it inside the power
strip, solder the inductor in series with the "line"
conductor, then have that strip feed all of the loads
that will ever be used, just as they're doing now.</big></font></span></font></big></font></div>
<div dir="ltr" align="left"><font color="#000000"><big><font
face="Times New Roman, Times, serif"><span
class="545082022-13092011"></span> </font></big></font></div>
<div dir="ltr" align="left"><font color="#000000"><big><font
face="Times New Roman, Times, serif"><span
class="545082022-13092011"><font size="2"><big>#3: Unasked
question: Why don't we do this for all of the
inverters?</big></font></span></font></big></font></div>
<div dir="ltr" align="left"><font color="#000000"><big><font
face="Times New Roman, Times, serif"><span
class="545082022-13092011"><font size="2"><big>First ..
because this issue didn't become a problem until quite
recently, and only then with some of the new
electronic chargers. Second .. t</big></font></span><span
class="545082022-13092011"><font size="2"><big>he "fix" is
needed only for a tiny fraction of the units we
manufacture, and we're doing all we can to help keep
the cost down for you and your customers.</big></font></span></font></big></font></div>
<div dir="ltr" align="left"><font color="#000000"><big><font
face="Times New Roman, Times, serif"><span
class="545082022-13092011"></span> </font></big></font></div>
<div dir="ltr" align="left"><font color="#000000"><big><font
face="Times New Roman, Times, serif"><span
class="545082022-13092011"><font size="2"><big>Our
higher-wattage inverters don't tend to be affected by
electronic chargers because the charger's capacitance
is a far smaller percentage of our large inverter's AC
output capacitance (compared to the XP125), and thus
isn't generally an issue. The only time a larger
(e.g. 1100 watt) inverter may be affected would be if
you were to plug in [say] six to ten of these
electronic chargers into that inverter all at once --
in which case the corrective action is an inductor
(the same as for, but a larger inductor than for the
XP125) .. and again one we'd provide free of charge.</big></font></span></font></big></font></div>
<b><br>
3. About my Wrenches post that turned out to include incorrect
information:</b><br>
<div dir="ltr" align="left"><big><font face="Times New Roman, Times,
serif"><span class="850465819-13092011"><font size="2"><big>The
source of the misinformation has been found. He was
forced to eat liver-pate and peanut-butter sandwiches on
raisin bread, while drinking warm milk and listening
repeated renditions of the Macarena Song.</big></font></span></font></big></div>
<div dir="ltr" align="left"><big><font face="Times New Roman, Times,
serif"><span class="850465819-13092011"></span> </font></big></div>
<div dir="ltr" align="left"><big><font face="Times New Roman, Times,
serif"><span class="850465819-13092011"><font size="2"><big>All
kidding aside .. you spoke with a tech who started on
the production floor and graduated into our Service
Department. He's actually very good at what he does,
but like any of us .. not perfect. He acknowledged
telling you the information you reported on the Wrench
BBS. Turns out it was based on his opinion rather than
fact. The overload protection circuits in our larger
inverters are obvious, as they involve [of course] more
[and larger] parts. The 125, being comparatively
low-power, has a physically smaller and less
visible protection circuit (but being only 1 amp output,
the circuit doesn't need to be very big). Since the
circuit didn't jump off the PC board to his eyes (so to
speak).. he [unfortunately] presumed it wasn't there --
and that's the information he passed along to you. He's
been apprised of the correct info, and he expressed his
sincere regret and apology for the inadvertent
misinformation he shared.</big></font></span></font></big></div>
<div dir="ltr" align="left"><big><font face="Times New Roman, Times,
serif"><span class="850465819-13092011"></span> </font></big></div>
<div dir="ltr" align="left"><big><font face="Times New Roman, Times,
serif"><span class="850465819-13092011"><font size="2"><big>I've
instructed our Customer Service Dept to fix the inverter
at no charge. I'm doing this not because of your post
on the BBS .. but instead, as you described it .. it's
the right thing to do. I will hope you'll be as vocal
on the BBS about good service .. and also to
correct/update the info to the Wrenches .. which I admit
was passed along to you in error .. but only if YOU feel
it's the right thing to do as well. As we all know of
our customers, happy ones don't tend to say much ..
while the rare unhappy ones never seem to be quiet.</big></font></span></font></big></div>
<div dir="ltr" align="left"><big><font face="Times New Roman, Times,
serif"><span class="850465819-13092011"></span> </font></big></div>
<div dir="ltr" align="left"><big><font face="Times New Roman, Times,
serif"><span class="850465819-13092011"><font size="2"><big>To
that end .. If there's ever anything passed along to you
from anyone at Exeltech that you question or make you go
"hmmmmm" .. you are welcome and encouraged to contact me
at any time for verification/clarification. It's much
easier to fix before it happens, rather than print the
proverbial newspaper retraction, which never seems to
get the high-level attention of the original erroneous
story.<br>
<br>
<br>
</big></font></span></font></big></div>
So I am being "<big><font face="Times New Roman, Times, serif"><span
class="850465819-13092011"><font size="2"><big>vocal on the
BBS about good service .. and also to correct/update the
info to the Wrenches". Exeltech is taking care of the
issue in a good way. I'm happy to pass that news along to
this list.<br>
Allan<br>
<br>
</big></font></span></font></big><font face="Times New
Roman, Times, serif"><b>Allan Sindelar</b></font><br>
<small><a moz-do-not-send="true" rel="nofollow"><font
color="#000099" face="Times New Roman, Times, serif"><u>Allan@positiveenergysolar.com</u></font></a></small><font
face="Times New Roman, Times, serif"><br>
<span style="font-size: 10pt;">NABCEP Certified Photovoltaic
Installer<br>
NABCEP Certified Technical Sales Professional<br>
New Mexico EE98J Journeyman Electrician<br>
<b>Positive Energy, Inc.</b><br>
3201 Calle Marie<br>
Santa Fe, New Mexico 87507<br>
<b>505 424-1112</b><br>
<a moz-do-not-send="true" rel="nofollow" target="_blank"
href="http://www.positiveenergysolar.com/"><u>www.positiveenergysolar.com</u></a></span></font>
<b><br>
</b><big><font face="Times New Roman, Times, serif"><span
class="850465819-13092011"></span></font></big><br>
-------- Original Message --------
<table class="moz-email-headers-table" border="0" cellpadding="0"
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<th align="RIGHT" nowrap="nowrap" valign="BASELINE">Date: </th>
<td>Sat, 10 Sep 2011 20:04:49 -0700 (PDT)</td>
</tr>
<tr>
<th align="RIGHT" nowrap="nowrap" valign="BASELINE">From: </th>
<td>Exeltech <a class="moz-txt-link-rfc2396E" href="mailto:exeltech@yahoo.com"><exeltech@yahoo.com></a></td>
</tr>
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<br>
EDITED:<br>
<table border="0" cellpadding="0" cellspacing="0">
<tbody>
<tr>
<td style="font: inherit;" valign="top">Hello Allan, and
Wrenches ...<br>
<br>
On Sep 9, 2011, at 6:30 PM, Allan Sindelar wrote:<br>
<br>
> I called Exeltech tech support and was told that the
XP125<br>
> lacks protection against AC overload!<br>
<br>
This is not correct.<br>
<br>
Every inverter we manufacture .. from our 125 watt XP125
(the model your customer owns).. to our largest 120kW 208V
3-phase systems .. all incorporate overload AND
short-circuit protection. They are also all protected
against over-voltage, under-voltage, and over-temperature.<br>
<br>
If you overload any of our inverters, they will limit their
output current to a safe level. If the overload is
excessive, either in duration or wattage (relative to the
inverter's rated output) .. the inverter will turn itself
off.<br>
<br>
> There's no circuit breaker or internal shutoff
protection,<br>
> and an internal fuse on the circuit board is included
only<br>
> to protect against reverse polarity. <br>
<br>
This is also not correct.<br>
<br>
To reiterate, internal over-current protection DOES exist in
the XP125 and all other models, regardless of wattage. This
protection is both electronic, and fused.<br>
<br>
While every inverter is fused - including the XP125,
additional over-current protection should also be installed
in the DC leads directly at the DC source - just as with any
other inverter. This protection can be in the form of fuses
or properly-rated DC breakers.<br>
<br>
Due to the low wattage of the XP125, it's virtually
impossible to blow the internal fuse due to overload. The
fuse exists to protect the DC wiring in the unlikely event
of a short circuit in the inverter input circuitry. The
fuse does not protect against reverse polarity. Should a
unit be connected backwards and damage the inverter .. we
typically repair it one time for this type of failure free
of charge.<br>
<br>
> And because the inverter has been in operation for 15
months,<br>
> this apparent failure isn't covered under the one-year
warranty.<br>
> Send it in, under $50 to repair. <br>
<br>
All of our out-of-warranty inverters are covered by a
flat-rate repair fee, regardless of age. We get units in
for repair we made 20 years ago, and they get fixed and sent
back. Fact is, if the inverter is repairable .. we fix it
and install any possible updates at that same time. The
cost is a flat rate, no matter what the failure, and this
includes the updates. This has been our policy for more
than 20 years. We occasionally get a unit that's been
totally destroyed by lightning or other causes - which
typically becomes an insurance issue. In such cases, we
work out a reduced cost for a replacement.<br>
<br>
> I wrote the customer about the load size and her
(edited)<br>
> answer is below. Apparently it wasn't even an overload,<br>
> just a failure, possibly related to poor power factor
in the<br>
> cordless drill charger. But I still have never heard of
an<br>
> inverter without some form of overload protection, and
it<br>
> seems to me that a unit this small especially needs it,<br>
> given how easily its capacity can be exceeded.<br>
<br>
This gets into a technical issue .. but one I'll describe in
brief. Certain of the new electronic chargers (such as De
Walt, Craftsman (usually made by De Walt, etc. and branded
"Craftsman"), and others are highly capacitive on their
input. In certain instances, this can drive our voltage
control loop unstable in the smallest inverters. Anything
that looks larger than approximately 1 microfarad might do
this - but again .. only for our *smallest* inverters, such
as the XP125 and XP250. Our larger inverters (>600W) and
our new designs do not exhibit this sensitivity.<br>
<br>
If any of our inverters are going to be used with a
capacitive load, let us know and we will provide free of
charge a component for to you to wire in series with the
inverter AC output that will counteract the effects of a
capacitive load.<br>
<br>
Also .. since a capacitive load appears to be the situation
with your customer, please contact me at the office on
Monday and I will authorize the repair of her unit free of
charge. We will also include the component (referenced
above) for connection in series with the inverter when you
re-install it.<br>
<br>
---------
<div>Regards to all...<br>
</div>
Dan Lepinski<br>
Sr. Engineer<br>
Exeltech<br>
<br>
<br>
<blockquote style="border-left: 2px solid rgb(16, 16, 255);
margin-left: 5px; padding-left: 5px;">
<div id="yiv835304206">
<div>
<div>
<div>On Sep 9, 2011, at 6:30 PM, Allan Sindelar
wrote:</div>
<br class="yiv835304206Apple-interchange-newline">
<blockquote type="cite">
<div> Wrenches,<br>
A bit over a year ago I built a mini-system for
a customer: One 135W module, SunSaver-10, 104
A/hr Concorde VRLA, Tri-Metric monitor and an
Exeltech XP125 inverter. All but the module were
installed in a plastic picnic cooler. The
customer was totally satisfied with the system
for this weekend getaway cabin system and used
it well within its bounds - a couple of lights,
mostly.<br>
<br>
Last week she called because the inverter had
failed. I called Exeltech tech support and was
told that the XP125 lacks protection against AC
overload! There's no circuit breaker or internal
shutoff protection, and an internal fuse on the
circuit board is included only to protect
against reverse polarity. And because the
inverter has been in operation for 15 months,
this apparent failure isn't covered under the
one-year warranty. Send it in, under $50 to
repair. <br>
<br>
I wrote the customer about the load size and her
(edited) answer is below. Apparently it wasn't
even an overload, just a failure, possibly
related to poor power factor in the cordless
drill charger. But I still have never heard of
an inverter without some form of overload
protection, and it seems to me that a unit this
small especially needs it, given how easily its
capacity can be exceeded.<br>
<br>
I have long respected Exeltech, one of few
domestic electronics products left. But this
incident is giving me pause. Morningstar's
SureSine claims extensive protection: "The
SureSine has extensive electronic protections
that will automatically protect against faults
and user mistakes such as short circuit,
overload, high temperature and low voltage
disconnect. Recovery from most faults is
automatic." It's looking better all the time.<br>
<br>
Has anyone else experienced a similar failure?<br>
Thank you,<br>
Allan<font id="yiv835304206role_document"
size="2" color="#000000" face="Arial"><br>
</font></div>
</blockquote>
</div>
</div>
</div>
</blockquote>
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