Boys and girls...
A winter project for sure, but getting the cats herded early.
Here's the poop.
One of my Jeeps has a dual battery system. Two batteries connected together (parallel) via a heavy duty relay.
I have one 0-50 amp current meter that is installed in the dash. A 50mv shunt is in the negative lead of the second battery. The meter displays the resultant voltage drop across the shunt.
I currently use the meter to monitor current draw from this second battery for secondary loads. But when this battery is being charged, the meter reflects downward, rendering the meter useless.
So, I am looking for a way to use the same meter and same shunt to display charging and discharge of this battery.
I know I can use a simple dpdt relay to reverse the meter leads to correct the meter's deflection, but would like a circuit to detect current going in one direction, then the other automatically. A LED (driven by the relay driver) would tell me what the meter is displaying i.e charging or discharging.
Being a bit greedy, could this same circuit be used to light up a second led warning me that excessive current draw is occurring?
Hall effect? SOunds good, but I've never used one before.
My thinking would be a op-amp reading the shunt, but I am not sure if the output would be positive (in ref to the ground ) or what nots?
There's a lot of sharp guys and gals here, so this one will be interesting.
thanks in advance..
mike
A winter project for sure, but getting the cats herded early.
Here's the poop.
One of my Jeeps has a dual battery system. Two batteries connected together (parallel) via a heavy duty relay.
I have one 0-50 amp current meter that is installed in the dash. A 50mv shunt is in the negative lead of the second battery. The meter displays the resultant voltage drop across the shunt.
I currently use the meter to monitor current draw from this second battery for secondary loads. But when this battery is being charged, the meter reflects downward, rendering the meter useless.
So, I am looking for a way to use the same meter and same shunt to display charging and discharge of this battery.
I know I can use a simple dpdt relay to reverse the meter leads to correct the meter's deflection, but would like a circuit to detect current going in one direction, then the other automatically. A LED (driven by the relay driver) would tell me what the meter is displaying i.e charging or discharging.
Being a bit greedy, could this same circuit be used to light up a second led warning me that excessive current draw is occurring?
Hall effect? SOunds good, but I've never used one before.
My thinking would be a op-amp reading the shunt, but I am not sure if the output would be positive (in ref to the ground ) or what nots?
There's a lot of sharp guys and gals here, so this one will be interesting.
thanks in advance..
mike