Bob K avatar image
Bob K asked

Orion-Tr Smart 12/12-30 Outputs Less Than Half Amps on 55% SOC LiFePO4. Why?

My Orion-Tr Smart 12/12-30 Isolated is outputting half or less of its rated amperage to my battery bank, and that amperage falls over the course of a few minutes. With its current performance, its not enough to cover my DC refrigerator (15 amps) and charge the battery bank while I'm driving. What could be causing this?

Here's my setup.

  • 2017 Toyota Tacoma w/ tow package (130 amp alternator) & travel trailer
  • Two 100Ah Battle Born LiFePO4
  • 6AWG positive and negative wires from starter battery to Orion and from Orion to batteries.
  • Orion S/N 2048 (appears to be post rev. for overheat changes)
  • Settings: Set to "Charger", Default LiFePO4, Smart Alternator, default vehicle shutdown
  • Installation: Open air, 70°F ambient temperature, in upright position
  • Victron SmartShunt


With the truck at idle after 2 minutes, the voltage at the starter battery posts is 13.5v. Input voltage to the cold Orion shows 13.1v. Cold Orion output voltage to the batts is around 13.5v.screenshot-20210903-174358.jpg

Output amperage of the cold Orion as read by the SmartShunt starts at about 18 amps, well below the rated 30 amps. Battery SOC is only 54%. Vehicle is still at idle speed.


Over just 10 minutes, the output amperage slowly falls to as low as 12 amps. At this point, the Orion is barely warm to the touch.


This occurs regardless of engine speed. The following video shows the low amperage output over time even when the engine speed is held at 2600 RPM. High RPM starts at 00:30 in the video.


Likewise, the input voltage to the Orion remains at 13.1v despite holding the engine speed at 2600 RPM.


Where should I begin looking to determine why the output amperage is less than half of rated amperage?

orion-tr smartamps
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

6 Answers
Matthias Lange - DE avatar image
Matthias Lange - DE answered ·

As long as you have loads running you will never see the full current at the SmartShunt.

Can you make a picture of the "engine shutdown detection" settings.

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Bob K avatar image Bob K commented ·

Thanks, Matthias, for responding. I don't have any loads on the battery bank during this testing so that I can analyze just the Orion's performance.

The engine shutdown detection parameters are at defaults for the Smart Alternator type.


At this point, I'm not having any issues getting the charger to turn on. I just can't get anything more than half amperage output. This snip is from the video with the engine held at 2600 RPM.


0 Likes 0 ·
Matthias Lange - DE avatar image Matthias Lange - DE ♦ Bob K commented ·

Your input voltage from the alternator is close to the shut-down voltage.
The charging current will be reduced if the input voltage is below the "delayed start voltage".
You have to adjust that settings or disable the disable the "engine shutdown detection".

2 Likes 2 ·
Bob K avatar image Bob K Matthias Lange - DE ♦ commented ·

Beautiful! That did it. Thank you. I changed the Shutdown voltage to 12.9v and now I'm seeing higher Output voltage (13.7v)...screenshot-20210904-093139.jpg

...and nearly full amperage output (27-28 amps).


I noticed that the charger also pulled the Input voltage down to 12.9v so I may need to reduce it more. I know how to read the graph more accurately now and I'll tweak the settings for best performance.

0 Likes 0 ·
Rob Fijn avatar image
Rob Fijn answered ·

Hello Bob K, one additional remark. It would be good to move the Black wire between the Shunt and the Negative battery pole to the battery Pole at the right hand side battery.
In this way the charger "sees" the same resistance to every battery.
You can read more about this in the Wiring Unlimited book that you can download from the Victron Energy web site.

Regards, Rob

1 comment
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Bob K avatar image Bob K commented ·
Thanks! I remember that theory now and will make the change.
0 Likes 0 ·
Bob K avatar image
Bob K answered ·

I'm using 6AWG stranded with a one-way circuit length of about 30 feet (so 60 feet total). As a result, I'm also experiencing about a 6% voltage drop (.8v) from the truck battery posts to the input side of the Orion. Voltage at the truck battery posts is 13.6v and 12.8v (Vin) at the Orion.


The installation graphic shows the non-isolated charger with only 3 screw terminals rather than the isolated charger with 4 screw terminals. When I first installed it, I followed Victron's guidance to use 16mm2 (~6AWG) for "10m". I didn't realize that this was the input positive conductor length only and that I should have calculated necessary wire diameter for the total circuit length (positive and negative conductors from the truck battery all the way back to the charger). That would have specified wire somewhere in the 1 to 3 AWG range (depending on which calculator I choose).


It works, but I'm still getting less than full amperage output from the Orion (22 amps or lower in the snip above) after about 10 minutes. The Orion will pull Vin down to whatever Shutdown Voltage figure I have set, but I might be able to toy with the Shutdown Voltage parameter a little more so that the Orion doesn't limit current. I'd really like to take full advantage of my 130-amp alternator.

1630779636351.png (6.5 MiB)
1630780417139.png (496.8 KiB)
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

klim8skeptic avatar image klim8skeptic ♦ commented ·

You could always wire the remote to an ''ignition" source, as per the manual.

That way the B2B would charge whenever the engine is runing.

1 Like 1 ·
burntjaffle avatar image burntjaffle commented ·
Hi Bob, I've just come across this thread and seeing the exact some issue in a 2021 Toyota which has a temperature compensating alternator.

I'm also using 6 AWG on a 10m run (5m pos, 5m neg).

Dropping the shutdown voltage helps but seems that my input voltage on the Orion drops to match it.

Amps on my shunt look OK though when I do this at around 27.

Do you think in your case that the issue is to do with the wire gauge not being thick enough and causing too much voltage drop?

0 Likes 0 ·
kevgermany avatar image kevgermany ♦♦ burntjaffle commented ·
Voltage drop is proportional to current (ohm's law) so at zero current you're going to see full voltage at both ends. At about 30A, you're going to lose nearly half a volt.
1 Like 1 ·
Bob K avatar image Bob K burntjaffle commented ·

Yes, my mistake was using wire gauge that was too small for my total circuit length (60 ft). When I probe the circuit, I'm getting a 0.8v drop over the circuit length.

When the Orion is in bulk charge, my voltages are:

13.6v at truck battery posts (truck at idle)
13.53v after the input side circuit breaker
13.05v at the Anderson connector (truck side)
13.05v at Anderson connector (trailer side)
12.8v at the Orion input screws

I'm also not completely educated on how the smart alternator in my '17 Tacoma is behaving since Bluetooth doesn't reach the Orion or my SmartShunt while I'm driving. In the meantime, I've slowly been adjusting the Engine Shutdown voltage downward. IIRC, I've got the Engine Shutdown voltage set to 12.3v (which means the truck battery voltage is around 13.1v before the .8v voltage loss). That consistently gives me about 22 amps out of the Orion and isn't depleting the battery in my Tacoma.

Long term, I plan to upgrade the wire gauge and maybe get the Bluetooth extender. Short term, I'd like to shorten my wire run using the technique described by this gentleman (ground at the rear of the truck rather than at the battery in order to use the truck chassis as a big negative "wire"). I'll need to check my ground wires to the Tacoma battery and make sure they're of sufficient gauge to handle this.

0 Likes 0 ·
dc4me avatar image dc4me commented ·
I don't think your 150 amp alternator is going to make a difference in what comes out of your charger as long as the charger has enough amps to run. Your settings need to be changed as others has posted.
0 Likes 0 ·
Bob K avatar image Bob K dc4me commented ·
I think what we're both working on is how to put enough of a demand on the Smart alternator such that it will come out of its "power saving" mode and output sufficient voltage and amperage to the Orion. To wit: Despite making the Orion put its full load on the truck's alternator, I rarely see my Smart alternator output more than 13.5v.
0 Likes 0 ·
dc4me avatar image dc4me Bob K commented ·
I have a 2021 Jeep without a regular or smart alternator. My selection was to go with regular alternator setting. Power comes from vehicle battery to power distribution box in rear of jeep. From there power feeds Orion. I set my start up voltage to 13v and disconnect at 12.4. Had to work with absorption values with "User defined" and all seem to work really good to charge LiPo4 battery. Where I going with this is I can't believe your smart alternator is going to put out a voltage less than 13 volts when running. Amps are a different subject. I am only imputing my experience because I am always wanting to learn something that I may not be aware off. Not at all to sound like an expert. Maybe I will learn more.
1 Like 1 ·
kevgermany avatar image kevgermany ♦♦ dc4me commented ·
There are other posts in the community reporting much less than 13V. Could well be correct. But also poor grounding/earthing can affect these values. It will also affect available power due to resistance.
0 Likes 0 ·
Bob K avatar image
Bob K answered ·

I upgraded to 2 gauge positive wire and grounded at the rear of the truck (as mentioned above) rather than running a completely separate negative wire. This results in 100%+ amperage output on the Victron DC2DC charger when the alternator is outputting appropriate voltage/current.

After a year of additional use, however, I still can't figure out the "smart alternator" on this 2017 Tacoma. With the charger in Bulk, the DC charger reads voltage input as low as 7v input, then up to 13.2v or so, and then back to 7v every 10 seconds or so, whether at idle or 2,000 RPM. I have the Input Voltage Lockout set for 12.5v, so of course, the charger constantly cycles from Off to Bulk. I have the Input Voltage Lockout set for 12.5v so that when I turn off the truck, the charger doesn't overly discharge the Tacoma battery. I find the Engine Shutdown Detection feature to be pretty much useless for this Tacoma. I'd still have to set the voltages so low that I'd risk over-discharging the Tacoma battery when I turn the truck off.

Even if I turn off both Engine Shutdown Detection and Input Voltage Lockout, the DC charger input momentarily dropping to 7v is enough for the Victron charger to say "Remote input inactive" and shut off charging.

I could set the Input Voltage Lockout much lower -- say, 11.5v -- to help keep the charger from cycling, but that really risks over-discharging the Tacoma battery when I turn the truck off.

Unfortunately, I still don't know what the alternator or the charger is doing while I'm going down the road because the Bluetooth signal doesn't reach that far.

I wish the Tacoma had a switch/mode (like GM vehicles) that told the smart alternator to provide a constant higher output. On GM vehicles, it's either turning on tow/haul mode or turning on the headlights. I can find nothing similar for Tacomas. Turning on the headlights and the AC full blast doesn't do it.

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

kevgermany avatar image kevgermany ♦♦ commented ·
Smart alternators are controlled by the vehicle ECU. The dealers may have the info.
0 Likes 0 ·
Bob K avatar image Bob K kevgermany ♦♦ commented ·

Yes, the ECM controls the "smart alternator" and the stock ECM mapping is, apparently, garbage. There appears to be no way to just put a demand on this "amazing" 130 amp alternator to signal the ECM to output higher voltage/current. One must retune the ECM.

0 Likes 0 ·
frans-d avatar image
frans-d answered ·

I had the same problem with my renault trafic van. My solution is that I need charge with the headlights on. This load keeps the alternator from powering down and maintains output voltage constantly at 13.8V

1 comment
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Bob K avatar image Bob K commented ·
I hoped that the 2017 Toyota Tacoma would have such a process, but alas it does not. While other vehicles, including my 2008 Yukon can force higher alternate output by turning on the headlights or the tow/haul mode, the Tacoma has no such process.
0 Likes 0 ·
Bob K avatar image
Bob K answered ·

I have reverted to turning off the Input Voltage Lock-Out feature and turning on the Engine Shutdown Detection feature.

Start Voltage = 13.50v
Delayed Start Voltage = 13.30v
Delayed Start Voltage Delay = 0s
Shutdown Voltage = 12.78v

The Engine Shutdown Detection feature automatically derates its load on the alternator as the alternator voltage output approaches the Engine Shutdown Voltage setting. Therefore, as the truck's ECM reduces alternator voltage, the Victron charger also reduces draw on the alternator. That keeps it from seeing those crazy low 7-volt readings (and constantly shutting off) that result from the DC charger putting a heavy load on the alternator at the same moment the ECM is reducing alternator output. At idle, I now get something like 8-13 amps through the DC charger.

I can't believe a modern automotive manufacturer would have no way to force high output from its "high output alternator" on a vehicle advertised for its towing capability, but here we are.

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.