I read this:
Which specifies that a SmartShunt, even when being used as a DC load meter, must be on the negative side. But in a vehicle, DC devices may/will have another path to ground that will bypass the shunt. I was expecting to install this on the positive side of my DC distribution panel.
What am I missing?
The primary purpose of the shunt is to monitor the battery.
The.battery bank must have a single connection from negative to the shunt. Battery is grounded through the shunt. Not directly.
Loads which bypass the battery will bypass the shunt and are not part of battery monitoring.
Shunt will not work in the positive battery feed.
It's up to you to design the installation this way.
That said the shunt can be set up as an energy meter, and will measure and report loads that it sees. And multiple shunts can be fitted to measure different parts of the installation.
> That said the shunt can be set up as an energy meter, and will measure and report loads that it sees. And multiple shunts can be fitted to measure different parts of the installation.
Yes, I want to use it as an energy meter. How does one do that on the positive side of a load?
@Adam Sherman Yes, I want to use it as an energy meter. How does one do that on the positive side of a load?
You have a negative lead going to this load?
That's where you place the shunt.
In a metal vehicle, such as a van, some of your loads will inevitably be grounded to the chassis–making it impossible to measure them via a negative shunt.
@Adam Sherman the shunt HAS to be on the negative side of a batter / load. It will not work with the shunt placed on the positive side of a load / battery.
In a metal vehicle, such as a van, some of your loads will inevitably be grounded to the chassis–making it impossible to measure them via a negative shunt.
Other than the starter motor and alternator, there is not many other loads that does not have a negative lead.
The negative and positive side of a load have the same current. From a measurement point of view it doesn't matter whether it's in the positive or negative cable. The shunt measures what goes through it's terminals.
The shunt's positive connection powers the electronics via the negative connections. If you put the shunt in the positive cables, there will be no power to the shunt electronics as there will be the same positive voltage on both sides of the PCB.
As I said before, you have to design cabling to suit the equipment. Otherwise use a different product. But don't expect the shunt to work in a way that it's not designed for.
