<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta content="text/html; charset=UTF-8" http-equiv="Content-Type">
</head>
<body bgcolor="#ffffff" text="#000000">
On 8/1/09 4:49 , Richard L Ratico wrote:
<blockquote cite="mid:121309632@retriever.VALLEY.NET" type="cite">
<pre wrap="">2)At a different training, by a well respected professional engineer who
frequently posts here, they were judged to likely be as effective in preventing
damage as a voodoo doll.
</pre>
</blockquote>
<br>
I'm not disputing this, but would like to know more. Perhaps our PE
will elaborate.<br>
<br>
<br>
<blockquote cite="mid:121309632@retriever.VALLEY.NET" type="cite">
<pre wrap="">4) Why aren't they UL listed?
</pre>
</blockquote>
<br>
According to Delta, it's because they don't fail on normal surges and
that is required as part of UL 1449.
<a class="moz-txt-link-freetext" href="http://www.leainternational.com/UL1449.aspx">http://www.leainternational.com/UL1449.aspx</a> mentions it starting in
2007:<br>
<br>
<i>Now, when UL tests a SPD, they will apply a fault current of 100A,
500A and 1000A for permanently connected SPDs and 50A and 150A for
plug-in and cord connected SPDs. These currents are applied using line
to line voltage in the line to neutral mode. During this testing, the
SPD must fail in a safe manner to be UL 1449 listed.<br>
</i><br>
<br>
</body>
</html>