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</o:shapelayout></xml><![endif]--></head><body lang=NO-BOK link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Great video thermal design.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>My knowledge on thermal design is only 30 minutes old, but my interpretation of the datasheet gives med<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>The regulator will reach 23°C/W above ambient. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Running at max 1.5A @ 5V = 7.5W.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>23C/W => 172.5°C -> To hot to handle<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>2 relays @ 80mA each ~ 0.16A @ 5V ~ 0,8W ~ 18.4°C above ambient. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>My conclusion is that adding a consumption of 160mA will raise the temperature 18.4°C above ambient. (This comes in addition to the current the OVMS module consumes.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Is this correct?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Regards<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Olav<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>Fra:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> ovmsdev-bounces@lists.teslaclub.hk [mailto:ovmsdev-bounces@lists.teslaclub.hk] <b>På vegne av</b> Mastro Gippo<br><b>Sendt:</b> 16. juni 2014 23:38<br><b>Til:</b> OVMS Developers<br><b>Emne:</b> Re: [Ovmsdev] OVMS - HW<o:p></o:p></span></p></div><p class=MsoNormal><o:p> </o:p></p><div><div><div><div><div><div><p class=MsoNormal>The 1.5A is not the whole story; you can watch this: <a href="https://www.youtube.com/watch?v=8ruFVmxf0zs">https://www.youtube.com/watch?v=8ruFVmxf0zs</a><o:p></o:p></p></div><p class=MsoNormal>Basically, if you had that 7805 on free air powering your two relays, it would (try to) reach about 170°C above ambient temperature. The PCB is a nice heatsink, but it is shared with the big GSM regulator, and that rises the temperature too.<o:p></o:p></p></div><p class=MsoNormal>By all means, experiment!! The 7805 has thermal protection, and you should test your circuit on the bench keeping a finger on the IC to feel if it gets too hot.<o:p></o:p></p></div><p class=MsoNormal style='margin-bottom:12.0pt'>You should take care of the increased ripple too, but a small cap should do the trick there.<o:p></o:p></p></div><p class=MsoNormal>Regards<o:p></o:p></p></div><p class=MsoNormal>MG<o:p></o:p></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'><o:p> </o:p></p><div><p class=MsoNormal>2014-06-16 23:09 GMT+02:00 Olav A. Antonsen <<a href="mailto:olav@ansit.no" target="_blank">olav@ansit.no</a>>:<o:p></o:p></p><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I got some help from a user on a Norwegian forum who pointed me to </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><a href="https://raw.githubusercontent.com/openvehicles/Open-Vehicle-Monitoring-System/master/vehicle/Car%20Module/v2-base/OVMS_V6A.pdf" target="_blank"><span style='color:#1F497D;text-decoration:none'>https://raw.githubusercontent.com/openvehicles/Open-Vehicle-Monitoring-System/master/vehicle/Car%20Module/v2-base/OVMS_V6A.pdf</span></a></span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Looks like a 7805-regulator is supplying the OVMS module with +5V @ 1.5A max.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><a href="https://www.sparkfun.com/datasheets/Components/LM7805.pdf" target="_blank">https://www.sparkfun.com/datasheets/Components/LM7805.pdf</a></span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>80mA won't be a problem then.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>--Olav</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>Fra:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> <a href="mailto:ovmsdev-bounces@lists.teslaclub.hk" target="_blank">ovmsdev-bounces@lists.teslaclub.hk</a> [mailto:<a href="mailto:ovmsdev-bounces@lists.teslaclub.hk" target="_blank">ovmsdev-bounces@lists.teslaclub.hk</a>] <b>På vegne av</b> Mastro Gippo<br><b>Sendt:</b> 16. juni 2014 23:03<br><b>Til:</b> OVMS Developers<br><b>Emne:</b> Re: [Ovmsdev] OVMS - HW</span><o:p></o:p></p></div><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>It may be a problem to get the 5V from the output of the regulator, but the nice thing about that module is that it is isolated; you can connect your own power supply and be 100% safe. These relays draw about 80mA each (just tested them, I have the same product at home), so if you turn them on one at a time and for short periods of time it should be ok (I don't know a lot about the termal design of the OVMS).<o:p></o:p></p></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>MG<o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:12.0pt'> <o:p></o:p></p><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>2014-06-16 22:37 GMT+02:00 Olav A. Antonsen <<a href="mailto:olav@ansit.no" target="_blank">olav@ansit.no</a>>:<o:p></o:p></p><div><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Hello</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>My knowledge of electronics is limited.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>As far as I understand the OVMS module is supplied with +12V via the OBD connector. What I don't understand is where the +5V comes from? </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><a href="https://github.com/openvehicles/Open-Vehicle-Monitoring-System/blob/master/vehicle/Car%20Module/v2-base/20120814-boarddesign.pdf" target="_blank">https://github.com/openvehicles/Open-Vehicle-Monitoring-System/blob/master/vehicle/Car%20Module/v2-base/20120814-boarddesign.pdf</a></span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I'm currently trying to control a relay using the RC3 output on the PIC18F2580 as a control signal to a rely on a relay module</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><a href="http://www.dx.com/p/arduino-2-channel-relay-shield-module-red-144140#.U59Qavl_t8E" target="_blank">http://www.dx.com/p/arduino-2-channel-relay-shield-module-red-144140#.U59Qavl_t8E</a>.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>The relay module needs to be supplied with +5V to drive the relays, and my plan was to get the +5V from the OVMS module using pin 13 on the HEADER 9X2.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>But I'm afraid I might blow something on the OVMS module if the relay module draws to many mA.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Any advice would be appreciated.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>--Olav</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p></div></div></div><p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:12.0pt'><br>_______________________________________________<br>OvmsDev mailing list<br><a href="mailto:OvmsDev@lists.teslaclub.hk" target="_blank">OvmsDev@lists.teslaclub.hk</a><br><a href="http://lists.teslaclub.hk/mailman/listinfo/ovmsdev" target="_blank">http://lists.teslaclub.hk/mailman/listinfo/ovmsdev</a><o:p></o:p></p></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p></div></div></div></div></div><p class=MsoNormal style='margin-bottom:12.0pt'><br>_______________________________________________<br>OvmsDev mailing list<br><a href="mailto:OvmsDev@lists.teslaclub.hk">OvmsDev@lists.teslaclub.hk</a><br><a href="http://lists.teslaclub.hk/mailman/listinfo/ovmsdev" target="_blank">http://lists.teslaclub.hk/mailman/listinfo/ovmsdev</a><o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p></div></div></body></html>