tag:blogger.com,1999:blog-3803330253605746037.post5991273079219191377..comments2023-08-13T10:10:02.076+02:00Comments on kaktus circuits: MightyWatt as a Li-Ion chargerJakub Polonskýhttp://www.blogger.com/profile/00934287694461790378noreply@blogger.comBlogger6125tag:blogger.com,1999:blog-3803330253605746037.post-37061801747546134152015-10-14T09:05:21.576+02:002015-10-14T09:05:21.576+02:00Hi Yousif, it is not absolutely necessary to calib...Hi Yousif, it is not absolutely necessary to calibrate but it will probably be few percents off. With calibration, you can get to around 0.3 percent relative uncertainty. Any calibration is better than no calibration.<br /><br />When MightyWatt is connected to Arduino, it shares its ground with the one on Arduino. And Arduino is grounded via USB cable to PC, which is typically earthed. MightyWatt also connects ground to the negative power terminal (PWR-) so the PC ground and PWR- are connected. If you need floating ground, you will have to use galvanic isolator (take a look at ADuM4160) or run the PC (laptop) from a battery, without any additional ground connections.Jakub Polonskýhttps://www.blogger.com/profile/00934287694461790378noreply@blogger.comtag:blogger.com,1999:blog-3803330253605746037.post-46016195367081562192015-10-14T02:24:57.945+02:002015-10-14T02:24:57.945+02:00Hi Jakub,
Thanks for that. I am just wondering al...Hi Jakub,<br /><br />Thanks for that. I am just wondering also whether it is absolutely necessary to calibrate the device. Will results be completely inaccurate? Will I get a good estimate? Also, I can't exactly recall where you said this, is there a pin (I think an analog pin) that has to be grounded?<br /><br />Thanks,<br /><br />Yousif<br />Anonymoushttps://www.blogger.com/profile/16382330677565144690noreply@blogger.comtag:blogger.com,1999:blog-3803330253605746037.post-79723191883999123722015-10-04T15:20:21.524+02:002015-10-04T15:20:21.524+02:00Hi Joseph,
It should work, apart from two things:...Hi Joseph, <br />It should work, apart from two things:<br />1) It won't work with Arduino Due so stick to Uno.<br />2) There is no LED to indicate the flowing current. It was a small addition in the later revisions. So the new sketch has code that toggles pin 5. You can delete the portion of the code or just leave it there, it won't do anything.<br /><br />Tell me how you succeeded or if you need any more help with the upgrade.<br />JakubJakub Polonskýhttps://www.blogger.com/profile/00934287694461790378noreply@blogger.comtag:blogger.com,1999:blog-3803330253605746037.post-52340177514508938002015-10-04T02:24:47.846+02:002015-10-04T02:24:47.846+02:00I have board revision 2 and firmware version 2.3.2...I have board revision 2 and firmware version 2.3.2. The code says the minimum board revision is 2.3; will it still work with revision 2?Anonymoushttps://www.blogger.com/profile/16382330677565144690noreply@blogger.comtag:blogger.com,1999:blog-3803330253605746037.post-58293705325587336192015-09-15T14:41:08.343+02:002015-09-15T14:41:08.343+02:00Starting revision 2, all the boards are 4-wire. Bo...Starting revision 2, all the boards are 4-wire. Boards with three digital pins are 2, 2.1, 2.2 and 2.3. The revision number should be written on the board left from the input terminals (2–2.3) or between the power supply and analog connection to Arduino (2.4, 2.5). Do you need help with upgrading to the latest firmware? I think that all the revisions can be adapted to the new firmware.Jakub Polonskýhttps://www.blogger.com/profile/00934287694461790378noreply@blogger.comtag:blogger.com,1999:blog-3803330253605746037.post-83332026853202612102015-09-15T09:34:51.050+02:002015-09-15T09:34:51.050+02:00Hi there, I was just wondering what board version ...Hi there, I was just wondering what board version is the MightyWatt with 4-wire configuration but uses three digital pins instead of four. I think it's r2.3 but I am not too sure.Anonymoushttps://www.blogger.com/profile/16382330677565144690noreply@blogger.com