I have a 24V Alternator that charges the House Bank. I would like to monitor the output using a smart shunt. However , the alternator is grounded to the chassis, i.e. if I connect the shunt between the negative of the alternator lead and the house bank, I do not capture all the current, as some of it will flow through the chassis . In the past I solved this , by installing the shunt on the positive side. Is that safe with the smart shunt, not sure if it likes its polarity reversed ?
It will not work with the shunt in the positive, it needs to be in the negative.
It's a tricky situation, not too sure how to overcome that. If nothing else connects to house bank negative via the chassis, then perhaps connect the shunt from battery negative and the shunt load terminal to the chassis. Difficult say for sure if this will work without knowing how your system is made up.
Hi,
No you cannot use the smart shunt with a reverse polarity.
If your alternator is a isolated earth return with a negative lead, you could insert the shut between it and the chassis.
Otherwise you will need to change the alternator for an isolated earth return model in order you can split the loads up effectively.
Thanks for the answers. I have tried isolating the alternator, haven't found the right bushings for the mount yet. isolating the engine block is not a good idea. Any way, i will probably go with a different shunt I have.
Hello,
can somebody explain me what shunt is installed here and if i can use this to measure the current and temperature without this special Alternator Regulator?
Why a SmartShunt with didn´t work in this application?
Is there any part that directly communicates with the Cerbo to measure the current from an Alternator or different loads on a positive wire?
Best regards Robert
The following picture I found here:
https://www.victronenergy.com/media/pg/Cerbo_GX/de/wakespeed-ws500-support.html
You can't use a smartshunt in the positive connection as it uses the negative for its own power supply - you would be connecting +12v as the positive supply and +12v as the negative so it would not be able to power up. There are also further considerations like needing to fuse the sense leads.
As far as I know there are no commercial products outside of the Wakespeed that can use a positive shunt and feed data to a GX device, and the Wakespeed is obviously very expensive! However if you're happy with DIY you could build one yourself. Here are a couple of threads that would point you in the right direction:
https://community.victronenergy.com/idea/139845/shunt-for-positive-connections.html
I plan on building one myself to measure output current from an Orion Tr Smart, so a BMS can ramp down the MPPT/Multiplus when the engine is running.
