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</o:shapelayout></xml><![endif]--></head><body lang=EN-NZ link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='color:#1F497D'>There are a lot of companies that produce small environmental monitoring devices that can take a digital input. These devices sit on your network and can be SNMP queried by MRTG, Nagios and other management systems.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>For example, this one:<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><a href="http://www.networktechinc.com/environment-monitor-micro.html">http://www.networktechinc.com/environment-monitor-micro.html</a><o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>We use their higher-end devices to monitor temperature, humidity, door sensors, and other things.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Your problem would be that in reality you want to *<b>count</b>* the pulses, and have MRTG query a total pulse count (this is far better than a rate as you will get more accurate data).<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Some of the devices may be able to give you pulse counts; others may just let you know the current state. You may be sufficiently knowledgeable to make a sinle pulse counter and SNMP agent using an Arduino or Raspberry Pi, which would be a cheap solution.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>This company makes SNMP-aware devices that can provide pulse counts:<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><a href="http://www.hw-group.com/products/damocles/damocles_1208_en.html">http://www.hw-group.com/products/damocles/damocles_1208_en.html</a><o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>I have not actually used one of these, but it appears to provide the required features, though it may be a bit big for your requirements.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Personally, I’d build a device to do it using a RasPi which would cost about $50 all in, plus a few hours coding up a daemon to count pulses and output this via the SNMP daemon.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>HTH<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Steve<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><div><p class=MsoNormal><b><span style='color:#1F497D'>Steve Shipway<o:p></o:p></span></b></p><p class=MsoNormal><span style='font-size:10.0pt;color:#1F497D'><a href="mailto:s.shipway@auckland.ac.nz"><span style='color:blue'>s.shipway@auckland.ac.nz</span></a><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:1.0pt;color:#1F497D'>(GNU Terry Pratchett)<o:p></o:p></span></p></div><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-left:solid blue 1.5pt;padding:0cm 0cm 0cm 4.0pt'><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> mrtg [mailto:mrtg-bounces+s.shipway=auckland.ac.nz@lists.oetiker.ch] <b>On Behalf Of </b>Nick price<br><b>Sent:</b> Tuesday, 19 May 2015 8:14 a.m.<br><b>To:</b> mrtg@lists.oetiker.ch<br><b>Subject:</b> [mrtg] power montor<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span lang=EN-US>The meter from our electric utility supplier gives out 3.5 volt pulses on 2 wires 1000 pulses=0.16kWHr.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>I need to get these pulses into MRTG. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Does anyone know where I can get a box that will output the pulses in a form that MRTG can read them preferably over Ethernet.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>I would also like it to interface to Nagios if possible.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Nick Price<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p></div></div></body></html>