Mercury Vapor / Hg

<body topmargin=0 leftmargin=0 marginheight=0 marginwidth=0> <table cellpadding=0 cellspacing=0 border=0><tr> <td valign="top" height=45 BGCOLOR="#808080" TEXT="#080000" bgproperties="fixed" background="03f00700eowhpc.gif"> <div> <FONT SIZE="5" COLOR="#FFFFFF" FACE="Arial" ><B>Lighting Information</B></FONT><B>     |     </B><A HREF="index.htm" TARGET="_top" TITLE="Lighting Information"><U><B>home</B></U></A></div> <div>                                                   </div> <div> </div> </td> </tr><tr> <td valign="top" height=435 BGCOLOR="#FFFFFF" TEXT="#080000"> <div> Mercury Vapor / Hg</div> <div>                              </div> <div> Mercury vapor was the first HID lamp (1930s).  Mercury vapor (MV) usually has an outer bulb and an inner bulb (arc tube).  The arc tube is made out of quartz and contains mercury and argon gas.  A mercury vapor arc tube normally has three electrodes. One electrode (starting electrode) is used for starting the main arc.  This means the ballast has to ignite the bulb using the peak/OCV voltage.</div> <div> When electricity is passed through the mercury/argon mixture this produces blue/green light.  Now a days mercury vapor bulbs are available with a phosphor coating.  This balances the light spectrum and improves the CRI making the bulb appear white.  Clear MV bulbs with an added blue glass filter will work as a black light.   </div> <div> MV lamps are usually being replaced with other HID lamps.  MV is the least efficient out of HID family.  Some MV (self ballasted) lamps can directly replace incandescent bulbs without the need of a ballast.  These MV bulbs use a filament for power regulation.  MV lamps are manufactured in many shapes (PAR, R, ED, BT, A, T) </div> <div> One reason MV is still used today is because the rated bulb life is very good (some 24,000+ hours).</div> <bR> <div> Mercury vapor lamps are used for:</div> <div> Replacing incandescent lamps</div> <div> General indoor lighting</div> <div> General outdoor lighting</div> <div> Security lighting</div> <div> Aquarium lighting</div> <div> Plant lighting</div> <div>                                                          <IMG SRC="17352080.gif" border=0 width="338" height="264" ALT="Bitmap Image" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> <B>Outer bulb:</B>  Available in coated and clear versions.</div> <div> <B>Outer bulb nipple:</B>  Bulb seal with two leads.</div> <div> <B>Arc tube</B> (quartz)<B>:</B> Where light is generated. Contains mercury and argon gas.</div> <div> <B>Nipple / Tip:</B> Where chemicals / gas are added in the manufacturing process.</div> <div> <B>Pinch seal:</B>  The arc tube seal with an electrode lead.</div> <div> <B>Pinch seal</B> (starter end):  The arc tube seal with two electrode leads.  </div> <div> <B>Resistor:</B>  Controls power going to the starting electrode.</div> <bR> <bR> <bR> <bR> <bR> <div> Text and Drawing by: Paul Erik Hirvonen</div> <bR> <bR> <bR> <bR> </td> </tr></table></body>