Can someone help me convert my DS2450 voltage reading to a 12VDC equivalent. I want to monitor a 12V battery in order to turn on a battery charger when the voltage drops below 12.4VDC I have used 2 equations Vb = (Vs * 10) +1 and Vb = (Vs * 11) _0.715 (Vb = battery volts, Vs = DS2450 volt.A, 2nd equation from OWFS). Neither of these is close enough to monitor my battery. The measured voltage at the input connector is 13.9VDC and the voltage from the DS2450 is 1.09697 which converts to 11.97 and 12.07 VDC. I am not sure whether to adjust the multiplier, the added amount or both. Thanks William
HVAC voltage conversion
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Thanks, I'll take idea 1. I already have a battery charger, they tend to burn out after awhile (the new ones even have a power sucking fan for cooling). It only needs to be on occasionally when the solar panels don't charge the battery enough. I had other applications in mind but will search for a different device to monitor voltages.
BraveSirRobbin
Moderator
Hi William;
I am not at all familiar with this Hobby-Boards part, but taking a quick look at the schematic, it appears that it is a 16-bit analog to digital converter with your choice of maximum inputs (you are probably using the one around five volts). The input looks like it's a 10:1 divider via some ratio resistors to get you a measurable range over five volts.
How are you determining the equations you reference in your first post? Seems to me you would want to do some sort of slope intercept conversion to get the "bit" digital number, then multiply that by the necessary conversion to voltage (which will also include the correction for the 10:1 input ratio).
Again, I have no experience with this and might not be correct in my above assumptions.
Also, if you are going to use this for turning a battery charger on and off, make sure you give yourself a "zone" in the on/off voltage value to avoid hysteresis. If you picked just one voltage range to turn on and off the charger, it would constantly cycle on and off. Better to pick an "off" voltage and then a different "on" voltage that is separated by some voltage value increment.
I am not at all familiar with this Hobby-Boards part, but taking a quick look at the schematic, it appears that it is a 16-bit analog to digital converter with your choice of maximum inputs (you are probably using the one around five volts). The input looks like it's a 10:1 divider via some ratio resistors to get you a measurable range over five volts.
How are you determining the equations you reference in your first post? Seems to me you would want to do some sort of slope intercept conversion to get the "bit" digital number, then multiply that by the necessary conversion to voltage (which will also include the correction for the 10:1 input ratio).
Again, I have no experience with this and might not be correct in my above assumptions.
Also, if you are going to use this for turning a battery charger on and off, make sure you give yourself a "zone" in the on/off voltage value to avoid hysteresis. If you picked just one voltage range to turn on and off the charger, it would constantly cycle on and off. Better to pick an "off" voltage and then a different "on" voltage that is separated by some voltage value increment.
