Well, sometimes it's easy to confuse things with how the terminology is used within Clark's charts & descriptions, but I imagine that reference in the ECN section refers to the area from the TK20 programming charts shown below. I would assume there was an update to the function, & by the looks of it, most likely the Invulnerability time was altered from what-ever it was previously, to the 10 seconds it is now:

<p align="left" class="MsoNormal"><span class="smalltxt1"> <font size="2"><span style="font-family: Tahoma"><span lang="en-us">I</span>R <span lang="en-us">B</span>attle <span lang="en-us">D</span>ata<span lang="en-us"> </span>Preset<span lang="en-us">: p</span>ress <span lang="en-us">"MTS" or "A/B" Key on TV remote to select</span></span></font></span></p><table height="64" border="1" cellspacing="0" cellpadding="0" class="MsoTableTheme" id="table46"> <tbody> <tr> <td width="40%" align="center" style="border-left:1.0pt solid black; border-right:1.0pt solid black; border-bottom:1.0pt solid black; border-top:medium none;mso-border-top-alt:solid black .5pt;mso-border-alt:solid black .5pt; height:16; padding-left:5.4pt; padding-right:5.4pt; padding-top:0cm; padding-bottom:0cm"> <p class="MsoNormal"><span class="smalltxt1"><span lang="en-us"> <font size="2" face="Tahoma">HL tank</font></span></span></p> </td> <td width="20%" align="center" style="border-left:1.0pt solid black; border-right:1.0pt solid black; border-bottom:1.0pt solid black; border-top:medium none;mso-border-top-alt:solid black .5pt;mso-border-alt:solid black .5pt; height:16; padding-left:5.4pt; padding-right:5.4pt; padding-top:0cm; padding-bottom:0cm"> <p class="MsoNormal"><span class="smalltxt1"><span lang="en-us"> <font size="2" face="Tahoma">7</font></span></span></p> </td> <td width="40%" align="center" style="border-left:1.0pt solid black; border-right:1.0pt solid black; border-bottom:1.0pt solid black; border-top:medium none;mso-border-top-alt:solid black .5pt;mso-border-alt:solid black .5pt; height:16; padding-left:5.4pt; padding-right:5.4pt; padding-top:0cm; padding-bottom:0cm"> <p class="MsoNormal" style="mso-pagination:widow-orphan"><span class="smalltxt1"> <span lang="EN-US" style="font-family:Tahoma;mso-font-kerning:0pt"> <font size="2">Reload Time = 3 seconds,</font></span></span></p> <p class="MsoNormal" style="mso-pagination:widow-orphan"><span class="smalltxt1"><font size="2" face="Tahoma"> Invulnerability time = 1<span lang="en-us">0</span> seconds<span lang="en-us">(Note1)</span></font></span></p> <p class="MsoNormal"><span class="smalltxt1"> <span lang="en-us" style="font-family: Tahoma"><font size="2">Max. hit can take = 5 hits,</font></span></span></p> </td> </tr> </tbody></table><p align="left" class="MsoNormal"><span lang="en-us"><font size="2" face="Tahoma">Note1: Reference setting for HL Tank


~ Craig ~
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