<div dir="ltr"><br><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">> what I meant was that we might want to distinguish between those that show information and those that show traffic signs to which you must obey.<br></blockquote><div><br></div><div>There is no way to distinguish this, unless you have access to the programming, and a fair number are automated to flex to traffic conditions.  <br></div></div><div class="gmail_quote"><br></div><div class="gmail_quote">The various American standards show these as Dynamic Messaging Signs, with other older content showing "character-matrix" Variable Messaging Signs, mostly with the 'text only' as VMS and the more modern "full-matrix" graphic technology as DMS. Other sources say the opposite. <br></div><div class="gmail_quote"><br></div><div class="gmail_quote">In Europe, they are still mostly known as VMS, there is some discussion here:<br></div><div class="gmail_quote">See "Dynamic message signs: differences between Europe and North America"                     

</div><div class="gmail_quote"><a href="https://www.traffictechnologytoday.com/opinion/dynamic-message-signs-differences-between-europe-and-north-america.html">https://www.traffictechnologytoday.com/opinion/dynamic-message-signs-differences-between-europe-and-north-america.html</a></div><div class="gmail_quote"><br></div><div class="gmail_quote">
The international ISO standards for intelligent traffic systems say "<span class="gmail-sts-non-normative-note-label">NOTE:</span> A Variable 
Message Sign is also named dynamic message sign. Both terms are 
considered as synonyms and can be used interchangeably." <br></div><div class="gmail_quote"><br></div><div class="gmail_quote">On that basis, the Solomon's choice ( <a href="https://en.wikipedia.org/wiki/Judgment_of_Solomon">https://en.wikipedia.org/wiki/Judgment_of_Solomon</a> ) would be to use to tag them something along the lines of "DMS/VMS","DMS-VMS", because almost every source (North American, British, European, etc.)  I found uses that sort of contraction as the convention, including the manufacturers. For any sub-tagging, the standards bust out further details according to the display tech, fixed or mobile, size, etc.</div><div class="gmail_quote"><br></div><div class="gmail_quote">The ones that change state according to a single variable or condition, like only speed, or lane open/closed, chains required, road flooded, etc. IMHO are more akin to the normal signs, in that even a normal parking sign has 'variability' of states built into the message. <br></div><div class="gmail_quote"><br></div><div class="gmail_quote"></div><div class="gmail_quote"></div><div class="gmail_quote">Ref: <a href="https://www.nema.org/Standards/Pages/Hardware-Standards-for-Dynamic-Message-Signs-with-NTCIP-Requirements.aspx">https://www.nema.org/Standards/Pages/Hardware-Standards-for-Dynamic-Message-Signs-with-NTCIP-Requirements.aspx</a></div><div class="gmail_quote"><a href="https://blog.ansi.org/2017/02/dynamic-message-signs-dms-electronic-road/#gref">https://blog.ansi.org/2017/02/dynamic-message-signs-dms-electronic-road/#gref</a></div><div class="gmail_quote"><br></div><div class="gmail_quote">Michael Patrick</div><div class="gmail_quote">Data Ferret<br></div><br></div>