Help with Charger 1 possibly false-detecting low voltage

Product Discussion Accessories
1

Hi,

TL:DR The Charger 1 is cutting out because it thinks the voltage is low (under 12V). But, the starter battery is actually on 13.6V.

Hoping anyone could help with my Charger 1.

It has been installed on my 2020 Toyota Hilux for about 10 months, charging an AC200L. It has been working fine charging at the output of 56V. I used all the cables that came with the unit and just added a 60A circuit breaker closer to the starter battery. The car has a smart alternator and the current starter battery is about 6 months old.

A few days ago, the Charger 1 started cutting out due to low voltage. It will run for about 10 seconds, then cut out, reset, then start up and charge again, then cut out. Rinse, repeat. I am able to tell it is due to low voltage because of:

  • The flashing LED on the Charger 1 matches that of the low voltage flash pattern as specified in the manual.

  • In the app, I can see the voltage gradually going down until it reaches on or around 12V before it cuts out. Sometimes I see 12.2V, sometimes I see 11.7V. I will assume this is a lag in the reading to the display in the app. The point is that it’s reaching 12V to cut out.

I have used a voltmeter to test and this is what I have found:

  1. When the car is off, the voltage at the starter battery is 12.6V
  2. When the car is off, the voltage at the cables just before it enters the Charger 1 on the input side (I removed them) is close to 12.6V
  3. When the car is on, the voltage at the starter battery is 13.7V
  4. When the car is on, the voltage at the cables just before it enters the Charger 1 on the input side is close to 13.7

This leads me to believe that there is minimal voltage drop from the starter battery to the Charger 1.

Now, what happens is this. When I turn the car on, before the Charger 1 starts actually charging, the app displays the input as 13.7V. This is correct. When Charger 1 starts charging, using a voltmeter, starter battery drops to about 13.6V and remains there. However, on the Bluetti app, the displayed voltage starts to drop to about 12.5V. From there, it just gradually drops until it goes under 12V then it cuts out. Meanwhile, the whole time, the voltmeter on the starter battery is reading 13.6V and after the Charger 1 cuts out, the starter battery reading goes back to 13.7V.

I have checked the following:

  • I have uninstalled the whole setup and checked the cables, connections, circuit breakers. Contacts are good and no corrosion.

  • I have turned on/off adaptive mode. Makes no change

  • Firmware is up to date

Other info to know is that I can run it on silent mode and it seems to work. I can also turn down the output voltage and it may run for longer before cutting out. I can turn it down very low (say, around 18v) and it will run fine. But that is not an acceptable charging speed.

Basically, how I am interpreting this information is that the Charger 1 is cutting out because it thinks the voltage is low (under 12V). But, the actual reading of the starter battery is 13.6V.

Anyone have any ideas? Or has my Charger 1 gone bad?

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2
  • Please first check what the error code is.
  • Check in the app to see if all firmware is up to date.
  • Try turning off the adaptive mode in the advanced settings of the app.
  • Click on the DC input icon in the app to enter the DC input information interface and check if the input voltage is normal.
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3

I have the same issue since first installed, have set the charger to silent which of course slows down the charge time which is why I purchased the charger1. Its installed on a LC200

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4

Another thing to note is;

Do you have any other high load accessories powered by the Hilux. i.e. in my Prado, I have an Aux Battery with a 20A DC-DC internal charger. Plus Anderson on bumper to charge my caravan at 30A. I noted with all that running, I could not get 56V output from the Charger 1. It’s just too much load for the “smart” alternator. (I think it is a 150A alternator and here in AU the Hilux shares the same drivetrain)

Therefore 20A+30A + the 45 or so amps from C1 = 95A total possible load. That coupled with some night driving using headlights, airconditioning, engine etc is more than the alternator can provide.

Even though your voltage may show good in the C1 supply cable, another check is with a clamp ampmeter, check the amperage of the supply cable when operating to see what the current provided is.

As an aside - I don’t use the C1 when towing the caravan. It is not installed permanently to the 4x4. When used, I power it from the Aux battery with a short home made, fused, input lead. This means I only use its 20A DC-DC as a load on the alternator, the aux bat acts as a “cushion” and I set output of C1 to no more than 30V. Depending on driving time, I can still get 56V output, but at a drain on the auxiliary.

30V charges at around 300W and with running an Engel fridge at the same time results in a net approx defecit of 5A on the aux battery. To compensate, I have a 110W solar panel on the roof that minimises that defecit. Sometimes it needs compromise and I don’t say that to criticise the C1 as every car is different and their alternators may not be big enough, it’s a great addition to power station charging.

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