Hi,
I get the current from battery monitor but the numbers are always positive, even when the battery discharges. How can I get the sign to distinguish beween charging and discharging
asked
only positive numbers in node-red from battery monitor
It looks like the value is represented as a signed 16 bit number.
I would use a function, containing:
if (msg.payload > 2**8) {
msg.payload -= 2**16
}
return msg;
It checks if the number is larger than 2^8. If so, it subtracts 2^16 from the value.
I had a similar problem. But my Batrium was sending 65536 - current if the current is negative.
So i used this:
msg.payload = msg.payload[0];
if(msg.payload > 20000){
msg.payload = msg.payload - 65536;
}
return msg;
