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ozarkjoe asked

Load cutoff discrepancies across 5 controllers (MPPT 75/15 to MPPT 100/20 48V)

I have 5 remote off-grid surveillance sites utilizing these charge controllers. The installation age ranges from ~5 years to 2 weeks. I have never had an issue with the load cutoff behavior until a couple of months ago when the days got shorter and cloudier. I noticed the issue because the remote camera feeds were unexpectedly shutting down. I've traced this back to load cutoff misbehavior. All 5 of these units are cutting off the load from ~0.5 to ~1.0 volt above the configured value. All controllers are configured and monitored via 'VE.Direct to USB' cables through 'SX Virtual Link' to 'Ubiquity' wireless LAN extenders. Some sites also have a PicoLog data logger attached for troubleshooting. I reset all to 'default' and made the following changes: ABS 28.6v, ABS Max Time 3.0 hrs., Float 26.6v, EQ 31v, load low 23.23v, load high 26.26v. Everything else is default, including 'streetlight = off'.

Has anyone else observed this behavior?

MPPT Controllers
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ozarkjoe answered ·

Example using cutoff at 23.23V. In this example the graph starts where the load has been configured as 'always on'. Two minutes prior to the first label I set the cutoff to 23.23V. Two minutes later the first cutoff occurs (first label). I again set 'always on' followed immediately by 23.23V cutoff and the failure occurred two minutes later (second label). I then set load to always on. The two-minute delay is preconfigured by Victron and not configurable. Note the voltage never dipped below ~24.2V, well above the configured 23.23V cutoff.

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ozarkjoe answered ·

Second example using VictronConnect's 'Trends' graph. This is similar scenario to the first example. Note voltage never got anywhere near 23.23V.


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ejrossouw avatar image ejrossouw commented ·
Since all of 5 of these exhibit the same problem, you will probably find a common factor such as a recent firmware upgrade to be the possible cause of the problem?
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ozarkjoe answered ·

Thanks ej, I had the same thought. There doesn't seem to be any way to get Victron directly engaged in this issue. I have a call open with a Victron distributor, but they are unable to duplicate and will not involve them. Any ideas on how to get Victron to support their products?

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Alexandra avatar image Alexandra ♦ commented ·

Taking it to supplier/distributor is getting Victron involved as the distribution network deals direct with Victron. These guys are trained and supported with spares etc.

If the supplier does not support them they are box movers and just there fornth money not service. See this page for whose responsibility is whose.

And where to buy.

You can get more direct support here. See get in touch at the bottom of the page.

And then as always with support cases time is needed to replicate if possible and diagnose. Then get back to you. Also there is probably a queue. I am sure you are aware of how much time set up takes, you have dedicated and spent time on yours.

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ozarkjoe avatar image ozarkjoe Alexandra ♦ commented ·
Thanks Alexandra,

Having been a worldwide 'Network Escalation Engineer' for Hewlett-Packard for more than 25 years, I am very familiar with all levels of customer/reseller and internal (1st , 2nd, 3rd, lab) levels of support. I've always enjoyed helping those I interacted with increase their skill level. I have provided the Victron distributor the duplication scenario and will wait a few days for a response. This vendor's initial response was a box swap (not uncommon and often correct). -Joe

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ozarkjoe answered ·

I have sent the following to the Victron distributor this morning:

----------------------------------------

I have duplicated this in my office:

New 100/20 48V controller (v1.61).

60V bench power supply (simulate solar panels).

100 OHM 50 Watt rheostat (simulate load).

I used 2 18AH batteries in series.

1) Set ‘Load operation’ to ‘User1’ (load off = 23.98V, load on = 24.5V).

2) Bring battery voltage above 24.5 via bench power supply to turn on load.

3) Turn off bench power supply.

4) Adjust rheostat to apply sufficient load to slowly bring the voltage down.

5) Observe premature load cutoff (see below).

Please escalate to Victron.

Load cutoff at 24.13 volts, well above the 23.98 configured volts (I have seen this difference as high at ~1 volt):

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Physical setup:

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ozarkjoe answered ·

On a side note, 'Smart BatteryProtect' works as it should (cutoff at 23.98v) when compared to the MPPT 100/20 48v (cutoff at 24.16v) in this test iteration:

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