Continue to Site

# [moved] SCALING THE MEASURED VOLTAGE VALUES'

Status
Not open for further replies.

#### KRISHNA1997

##### Newbie
Let us take an example that I have a battery which voltage of 48volts and by using a load charger and I am continuously discharging the battery by using a voltage sensor which gives the voltage values linearly but I need to scale down those values should be in between 5v to 15v otherwise in between ed30-50mA. How to sort out this problem can someone help since I am a mechanical background I don't have enough knowledge in Electronics.

#### wwfeldman

48V is a single voltage - it is generally easy to scale that to another single voltage , say 16 V

scaling can be created to to scale one range to another range.
say range A is 36 to 48V and you want to scale it down to range B, 5 to 15V

you will need to specify what range you want to scale to 5 to 15 V

sorry, i do not understand what you mean by this:
"otherwise in between ed30-50mA."

#### d123

Hi,

Maybe start by 15V/48V and 5V/?V will tell you the ratios needed. From there you can decide if a resistive divider will suffice or will need an op amp to fit the desired scale. Resistive divider only if the ratios are identical

For a resistive divider, decide on a total resistance value, multiply it by the product of 15/48 and that will tell you what value the lower resistor needs to be. Subtract total resistance from lower resistor value for upper resistor value.

##### Super Moderator
Staff member
A resistor divider comes to mind.

Install a zener diode inline if you want expanded scale readings.

48V is likely to generate waste heat in resistors and diode, thus you need to consider Watt ratings. A general approach is to use high ohm values, yet not droop due to whatever equipment you attach.

Status
Not open for further replies.