Source for bidirectional DC power meter?

[mystryda]

I want a DC power meter that measures voltage as well as current and power (instantaneous and accumulated) "both directions," such that I can measure how much energy I use when I ride and then again how much energy is pushed back in while charging.

I have already have a bidirectional DC power meter that looks just like this, except that it's labeled "Lemonhobby." It looks almost identical to this:

I got another one (the one pictured), and when current flows from source to load it doesn't measure it.

I got one that looked like this, and it also only measure from source to load (and shorted the connection at "source" when the voltage was higher than load!)

Anybody know where to get one that measures current in both directions??

Thanks!

 

[john61ct]

Note that a two-way unit will not show the totals for each direction, but

the **net** total, one direction being "input" say to a battery, the other being loads, the net loss or gain calculated.

With Peukert factor, CEF, Ah capacity may qualify as a battery monitor, guesstimates SoC%.

If you just want totals in each direction, use two one-way meters.

There are dozens of cheap units, under say $100, problem is identifying those with robust build quality.

Powerwerx is a well liked vendor, theirs looks like your first one

https://powerwerx.com/watt-meter-analyzer-inline-dc-powerpole

 

[john61ct]

TY01 8-60V Coulomb Meter LCD Battery Capacity Tester Power Level Indicator 

Also TK15

 

[john61ct]

TF01N 50V 100A Coulomb Counter Coulometer For LiFePO4 Lithium LiPo/LiIon Battery 12000761
https://s.click.aliexpress.com/e/LQWE9nag

 

[dustNbone]

I used one of these and a little DPDT switch to reverse the shunt sense wires. Not automatic but as long as I remember to flip the switch it does the job.

https://www.ebay.ca/itm/Voltage-Cur...tery-Monitor-DC-6-5V-100V-0-100A/113145508572

 

[amberwolf]

Cycle Analyst (any version) does this (and can do a lot of other things, too, if you have the need), but costs more because of the other features, etc.

It also measures and displays the current in each direction separately, as well as cumulatively, in case you need to know the separate currents, not just the total.

Same for the amps, it has both Amin (which will show the most negative value) and Amax, which will show the most positive value.