I just acquired a Truck and Truck Camper and I suspect I have issues somewhere in my charging system, but I’m also unaccustomed to the setup and don’t know what is normal.
The truck is a 2015 Ford F350 with a single “Extra Heavy Duty Alternator” (as stated on the window sticker, however I haven’t confirmed it is original). I believe all alternators from Ford 2015 and later were “smart.” The camper has 200w of solar with a Victron MPPT 100|20 (solar seems to work fine), a Victron Orion-Tr Smart 12|12-30 isolated DC/DC charger, and 1 Litime 12v 140ah lithium battery.
When driving at night (no solar), I’m generally getting 17-20w of charging power as reported by the litime battery. The DC-DC charger shows 13.1V of input and 13.3V output. All lights/appliances in the camper were off.
Before I start tracing cables and bust out my multimeter, can someone confirm that I should be getting more incoming watts into the litime (I have to be, I think!?). I also noticed that the DC to DC charger is stating it is in absorption phase when the battery SOC was reporting 68% (later in my drive it went to float, even when the battery was at 69%) . I believe it should be in the bulk phase. Sometimes it does report bulk phase, but I’m still only getting 17-20w.
Thank for the reply @TherealKT . Here are my Orion DC/DC settings. Input voltage lockout at 11.0 because I specifically saw a message stating “Charge is disabled due to Input voltage lockout.” It was 12.5V previously.
I started tracing cables and still don’t see an obvious reason my DC to DC charger would be sending only 17w to the battery. Surely the whole point of a DC to DC charger is to provide much more than that?
Yes, it should be charging at a higher rate based on that info. It is interesting that in “absorption” it is charging at such a low voltage (13.1). It should be constant voltage of 14.2 at that point per your settings. Smart alternators can do weird stuff. Perhaps try setting it to “regular alternator” and see what happens. Can you tell what the cable size is? Also, I am a little prejudiced to LiTime batteries at this point due to weird BMS issues they have had. Unlikely that’s the problem but I would suggest a Victron Smartshunt to get the most reliable battery state of charge.
Thanks for the response @TherealKT . I will check the cable size (pretty sure 6 AWG), but will confirm. I need to research the benefits of a smartshunt. I do have a clamp meter around here somewhere.
What is probably happening is the input voltage / current supply to the Orion is being limited by something. You have set engine shutdown detection to 13.1V and your screenshot shows the Orion input at 13.1V. What is happening is when the input power is limited, the Orion reduces charging power to maintain the 13.1V shutdown voltage. As the charging power is limited you can only.lift the output to 13.3V. Read the manual se tion of engine shutdown, all this is explained.
The input could be limited by amongst other things
Large loads on the alternator / starter battery.
Failure of the alternator.
Slipping of the alternator belt.
Loose connection, failing switch or fuse between the alternator and the Orion.
The Orion is doing what its supposed to do. The engine shutdown detections “shutdown voltage” is set to 13.1V, this means that the input current will be regulated at that voltage. Only once the current has to be regulated down to zero and the input voltage is still below 13.1V then the engine is detected as stopped. You can see this in the sequence at points two and three
If you apply a load to a cable, said cable will loose some voltage across its distance, so naturally with increased current the Orions input voltage will fall a bit. If that voltage loss is too big, the Orion dynamically reduces the input current. That is happening at the shutdown voltage setpoint.
Very likely your starter batteries resting voltage is far lower than 13.1V, so you can very likely lower that number further. The settings in general suggest that this Orion was never really checked to work with the particular smart alternator, all settings look original. So far ive not seen an Orion work fine with all original settings, ive always had to set the engine shutdown detection to the specific alternator.Checking the input cabling surely also helps. Its also likely that the cable gauge is just too small. Or something is loose or corroded.
The new lockout voltage that youve set is very low, id personally would set that a bit higher again. But granted the original 12.5V can also already be a bit high depending on the vehicle.
This is not a bad thing. Once the engine is running and the alternator starts charging the starter battery again, the Orions input voltage will raise above the restart voltage again and charging will commence again automatically.
I have a very similar system in a 4x4 wagon. 220W solar PV via MPPT 100/20 and a Orion XS feeding from alternator to a 12.8V x 100 Ah LiFePO4.
The battery and devices are in the rear of the car near the 12V fridge so the cgarging cables from start battery to Orion XS are long. Volt drop is an issue when using engine run detection. It may be worthwhile to trace those cables, paying attention to all joints, earth connections and fuses.
If the alternator is only putting out 13.3V and the engine run threshold is set at 13.1V you may only get an amp or two charging current. The orion will dial back the charging current to reduce volt drop and keep the unit running. Please reset the lockout voltage back to default.
My system runs ok with the engine off threshold at 12.9V. My alternator is regulated to around 13.8V.
Another thing I have observed is that if the house battery is isolated, the Orion will turn on when the engine runs but cannot charge anything. It then goes into absorption and eventually storage mode but may report weird voltages. With your system reportng absorption mode at low voltages and the BMS showing the battery far from full there may be a disconnect or high resistance somewhere between the Orion output and battery.
Hi @JamesV , @chrigu , @pwfarnell , and @TherealKT . Thank you all for your responses. I have confirmed that the cabling is 6 AWG. It is quite long, probably 20’, traveling the distance of the truck to the rear of the truck camper. I have confirmed all fuses are good and grounds are tight. I have also confirmed that the original 200amp extra HD alternator is present. I changed the lockout voltage values back to defaults as suggested by @JamesV
I have read the these responses several times and consulted the Orion documentation on engine shutdown detection, but I am still having a hard time understanding whether I should raise or lower the “Shutdown voltage” (currently 13.10). My hunch is that I should lower it, but I’m still not “getting it” and don’t really understand what the value should be.
The difference between your normal alternator charging voltage and the shutdown voltage that you select is the “headroom” you are giving yourself for the voltage drop incurred to drive a current in your charging circuit.
Remember the charging circuit is the 6 AWG charging wire plus the negative return path plus all fuses and connections.
At the same time, if you select a shutdown voltage that is lower than the fully charged start battery, the Orion will continue to run, draining your start battery even when the engine is off, until the shutdown voltage is reached.
So you are looking for a happy medium. Ideally the system should keep running when the engine is at idle but it should stop charging within a few seconds of switching the engine off .
In your vehicle you seem to have a low charging voltage (13.3V?) and this appears to be limiting the amount of current that your long charging circuit can provide.
Your current shutdown voltage setting is 13.1V. Try reducing it to 13.0V or 12.9V to see if you get a higher charging current.
Hi @JamesV . Thank you for your suggestions. I tried lowering the shutdown voltage to 12.9. And for the first 15-20 mins of the truck running, I was getting better (but still not great) results, 12.5V Input to the Orion, 13.6V Output to the Battery. At this time the Battery BMS was reporting 13.5V, 5amps and 70w of charging power. I wasn’t driving, just had the truck parked/idling. However, after 15-20mins, things went downhill. The Victron charger app was reporting Input Voltage as low as 11.0V (but was mostly between 11.5 and 12.3). Strangely, I did not see any messages reporting that the charger was disabled due to voltage lockout (which was set to 12.5 when I started the engine, but I backed down to 12.2 once I saw the voltage drop). I used my clamp meter to take amp readings from the cabling near the starter battery all the way (21 feet away-6 awg) to where it gets to the charger and didn’t notice much difference. I’m baffled.
Ok. The Orion should have deactivated charging once the input voltage dropped below 12.9V. The app display should be reading “Off” and not “bulk” with that low input voltage. Its a pity it is not reporting the input and out currents along with the voltages.
Also, no alternator should be at 11V when the engine is running, smart or not. So there is a complex problem here (i.e. more than one issue).
At this stage I would go back to basics…
Starting from the source (alternator):
Disconnect the Orion charger (pull fuse or disconnect the input cable at the start battery).
Get the vehicle charging system checked out by an auto-elec if necessary. If you have a decent multimeter, what is the voltage at the start battery when engine is off, while idling just after starting the cold engine and after the engine has reached normal temperature following a drive? Does the voltage change when a load is applied (turn on headlights, demister, fan etc) with the engine running. This will give some idea of start battery and alternator health. I suspect the alternator or start battery has issues.
If vehicle charging system checks out, reconnect the Orion and reset it to factory defaults using the app. Then select the Li-ion charge control preset and enable engine shutdown detection. Does it start charging when the engine starts and stop when engine shuts down? What charging current at Orion input and output? If running for some time does the Orion reach 14.2V output and transition from '“Bulk” to “Absorption” and then to “Float “ or “Storage” at 13.5V?
Now reduce the shutdown voltage to 12.9V You should get a slight increase of a few amps in the charging current during bulk charge.
Good luck. There is a possibility the Orion unit is faulty but those low alternator / start battery voltages are the biggest red flag for me.
Ok, @JamesV , here are the results of today’s experiments.
I completely disconnected the wires that go to the DC-DC charger at the starter battery. I confirmed the Orion charger could not be found in the Victron app device list.
I took a starter battery (Battery has sticker stating Dec ‘24) voltage reading after the car had been sitting cold for about 24 hours: 12.5V
Started the truck and immediately took another reading: 14.43V
5 minutes afer I started the truck took another reading: 14.45V
I turned the wipers, radio, seat heaters, and vents fans all on and took another reading: 14.39V
I drove the truck around for 20mins, came back and parked and took another reading: 14.46V
I’d say the Alternator seems ok. The battery is about 16mo old and should be ok, but the initial reading of 12.5V might be a lil low.
Ok. Alternator and start battery are good. 12.5V is around 80% to 90% SoC, maybe more if your ambient temp was cooler than 25°C/77°F.
Alternator at 14.4 to 14.5 is a touch high for a flooded battery but OK for AGM.
So now we have to focus on the Orion and cabling because some of those 14 .4V are going missing between the start battery and Orion input terminals. At the low charging currents you are seeing there are three possibilities:
Orion is faulty
Resistance in the positive cable or the earth/return path between start battery and Orion. I had this on my system recently. Was getting only around 5A. I found corrosion between the bolt and lug at the chassis earth near the house battery. The bolt was very tight but still making a poor connection.
Resistance in Orion output to house battery (although this does not explain the low input voltages)
If your cabling checks out then the Orion may be faulty.
At the start battery, is your 6AWG charging cable connected directly to the battery terminal with a fuse nearby? I ask because some vehicles provide a separate fused utility connection that would give us something more to check.
Hi @JamesV . Thank you again so much for all of your help. Is there a tip jar somewhere? Yes there is a 40amp fuse located at the start battery for the positive cable that runs to the Orion (shown here unattached from yesterday’s testings). There is also a second fuse for the positive cable between the DC to DC charger and the lithium battery (no photo of this one readily available at the moment).
I have two questions about cabling.
The negative cable from the Orion is screwed into the truck chassis near the starter battery. In the same screw eyelet is another cable that runs to the negative terminal of the starter battery. I think this ok, but just double-checking.
On the other end of things, at the DC to DC charger on the camper, the housing is made of plastic, so the negative cable goes straight to the negative terminal on the lithium/camper battery, however, there is a grounded cable from the camper that touches the same connector at the negative terminal (once you tighten down the negative screw into the battery they all get “sandwiched” together). Is that ok?
Thank you for the mention of corrosion, I will examine all eyelets and connections and make sure they are clean.
I’m going to have to read your system descriptions fron the start and draw myself a diagram. The earthing of the unit in the trailer to trailer chassis and other earths to vehicle chassis gives potential for some issues. Ideally you want everything on the same earth plane. Anywhere that current flows through the earth cables there is volt drop and so the negative terminals on the various components end up at slightly different voltages but they all think they are at 0.00V.
@JamesV is giving excellent troubleshooting advice here. Your grounding as described should work assuming its all good connections. It does leave room for failure points and resistance when there are more connections than necessary. You may consider just running all your Orion grounds to the batteries just to make sure that part isn’t a factor. Also, not a clear culprit of your problem, but that 40A breaker looks to be a cheap “amazon special”. It would be worth replacing it with a quality mega fuse. You could check voltage drop between the two sides of the breaker or just remove one side of it and bolt it temporarily to the other side and see if the Orion operation changes. Like I said, just temporarily, this will leave the circuit without protection. However, tests have shown that many of those cheap breakers don’t work correctly anyway.
When it comes to a “tip jar” the best you can do is click “solution” on @JamesV ‘s post that ends up being the most helpful to you. I am sure he will appreciate it.
Hi @JamesV and @TherealKT Thanks for the responses. Let me draw up a crude diagram and post it here. I aim to do more troubleshooting this weekend and I will remove the “amazon special” fuse just to be sure it’s not culpable.
