Help Epever Tracer BN series 40 amp controller not working

[garyr]

Hello from Ohio,
2006 sprinter conversion van.
Building system using 16cell 3.3volt = 200 ah 12 volt battery bank last year
Purchased and installed Tracer 4250 BN charge controller a year ago. Mounted but never integrated into van. Also have the mt-50 meter.
Just purchased 3 150 watt panels and in process of installing, hopefully hinged roof mounted.
Just last week started using the charge controller with circuit breakers, manual cutoff etc. and temporary solar panel hookups.
Everything worked fine for a few days. Using the OK button on the MT-50 remote meter I could turn on/off the system load
from the charge controller. Although many times you would have to push the button several times for it to work.
NOW I cannot get the charge controller to turn on the load. The solid green light beside the "button" is on and with the panels
attached the left side green light blinks but I cannot get the red button light to turn on either manually or with the remote. All other functions
of the remote meter seem to work properly.
So far the highest the battery bank has gone is 13.7 volts and the lowest is 12.3 ...currently 13.4 ...No moisture problems or dropping
or any of that sort.
The only variable here is that I have a 3000w pure sine inverter wired directly through a battery protector as seen in one of that Will Prowse(?) fellows' utube
videos that energizes the entire 12 volt system when the inverter kicks in the 120v /12v converter. I have made sure though to turn off the charge controller load
whenever the inverter is to be used.
Can someone tell me where to look or what I may be doing wrong?
regards gary

 

[Forbisher]

You wired the 3000w inverter directly to what?
Battery?
Load terminals on SCC?

What do you have connected to the Load terminals? How many amps?

3000 watt inverter is 250A on a 12V battery which needs beefy wires.

Hello from Ohio,
2006 sprinter conversion van.
Building system using 16cell 3.3volt = 200 ah 12 volt battery bank last year
Purchased and installed Tracer 4250 BN charge controller a year ago. Mounted but never integrated into van. Also have the mt-50 meter.
Just purchased 3 150 watt panels and in process of installing, hopefully hinged roof mounted.
Just last week started using the charge controller with circuit breakers, manual cutoff etc. and temporary solar panel hookups.
Everything worked fine for a few days. Using the OK button on the MT-50 remote meter I could turn on/off the system load
from the charge controller. Although many times you would have to push the button several times for it to work.
NOW I cannot get the charge controller to turn on the load. The solid green light beside the "button" is on and with the panels
attached the left side green light blinks but I cannot get the red button light to turn on either manually or with the remote. All other functions
of the remote meter seem to work properly.
So far the highest the battery bank has gone is 13.7 volts and the lowest is 12.3 ...currently 13.4 ...No moisture problems or dropping
or any of that sort.
The only variable here is that I have a 3000w pure sine inverter wired directly through a battery protector as seen in one of that Will Prowse(?) fellows' utube
videos that energizes the entire 12 volt system when the inverter kicks in the 120v /12v converter. I have made sure though to turn off the charge controller load
whenever the inverter is to be used.
Can someone tell me where to look or what I may be doing wrong?
regards gary

 

[garyr]

OK the 3000w inverter is wired directly to the battery through the Victron BP 12/24 100
using #2 welding cable for pos and neg with 300 amp fuse.

The controller load pos is a #2 welding cable pulling at most 20 amps at any given
time...9 -5w LED house lights and the 12v fridge.
controller load neg is #4 welding cable to a junction block

 

[snoobler]

OK the 3000w inverter is wired directly to the battery through the Victron BP 12/24 100
using #2 welding cable for pos and neg with 300 amp fuse.

The controller load pos is a #2 welding cable pulling at most 20 amps at any given
time...9 -5w LED house lights and the 12v fridge.
controller load neg is #4 welding cable to a junction block

BP should never be used with an inverter - only direct DC loads.




It can be used to cycle the power switch on the inverter.

There have been a number of recent posts regarding failed Epever controllers.

 

[garyr]

My problem is not with the battery protector.
The scc is the problem and it is wired independent of the bp and one is turned off
when the other is on although the charge controller is inputting voltage when the
inverter is in use.

 

[snoobler]

My problem is not with the battery protector.
The scc is the problem and it is wired independent of the bp and one is turned off
when the other is on although the charge controller is inputting voltage when the
inverter is in use.

I'm not saying they're related. I'm saying you shouldn't install the BP in the way you have described. It's not intended for that use.

I'm implying that you have a defective controller if you're using it within its rated limits.

 

[garyr]

Question:
Could the system, as I have it now wired, have caused the failure of the scc.

Improper or not, the Inverter switched on activates the entire 120 volt system.
Incorporated in the van's system is an ac to dc converter causing 12.6 volts to
energize the 12 volt system including charging the battery.
Could this have caused the scc failure?

 

[snoobler]

If you are connecting/disconnecting the SCC from the battery with the panels attached, there are some instances where this could damage the unit. MOST SCC recommend that the batteries be connected before the panels. This is primarily to ensure the proper battery voltage is sensed, i.e., 12V, 24V, etc. Only in rare cases has disconnecting/reconnecting the SCC from the battery while the panels are attached damaged the SCC.

 

[garyr]

The scc remains attached to the battery since the initial hookup.
I have though disconnected/reconnected the solar panels intermittently, unswitched/ unfused
while preparing to mount them permanently.

 

[rickst29]

Let's go back to the beginning, and first thing: Disconnect the Inverter, it might be misbehaving. (And it is connected on the battery side.) In post #1, to told us that you have a "16cell 3.3volt = 200 ah 12 volt" battery string, but you have not told us either the chemistry of those batteries or the number of BMS systems involved. Is it one giant 4x4, with all 16 cells running through one BMS, or is it built as multiple independent batteries? Thanks in advance.

The most important question is: What battery chemistry, and what EpEver charging profile are you using? If you are subjecting LFP batteries to an extremely high 'equalization' charge, you have made a mistake - and the batteries (rather than the controller) might be damaged.

Tracer "BN" controllers, unless failed, can handle "hot" disconnect and re-connect on the Solar side pretty well. If it has broken (and it very possibly is broken), it is more likely some "craziness" on the battery side, or a simple defect in materials and workmanship. It would be WONDERFUL to provide us with your charging parameters, as read off from the MT-50. Along with the chemistry and layout of your battery bank. Then, some of us might of ideas for you.
- - - -
Confirm the panels charging the battery bank with the SCC first. Only later connect the inverter.

 

[rickst29]

Question:
Could the system, as I have it now wired, have caused the failure of the scc.

Improper or not, the Inverter switched on activates the entire 120 volt system.
Incorporated in the van's system is an ac to dc converter causing 12.6 volts to
energize the 12 volt system including charging the battery.
Could this have caused the scc failure?

There is a ton of "badness" if you have a loop from the Inverter (discharging the battery and creating 120v, wasting ~15% of power while doing that), providing power INTO the AC-->DC Converter (trying to recharge the Battery, and wasting another 15% of power while trying to do that). But none of that should be fatal to the Trace SCC, unless extreme heat has come in from the battery connection. This "badness" would be more likely to overheat undersized "12v" cables (creating a fire hazard), and waste a ton of power, dragging the Tracer "BN" "battery voltage" down to a point where it refuses to function.

At that point, your batteries are likely already ruined and unrecoverable, you've got another problem on your hands. Don't ever let a
"loop" like this occur.

 

[garyr]

Thanks for listening,
each cell: Nominal Voltage 3.2V Chemistry LiFePO4
Nominal Capacity 50 Ah Cell Type Prismatic

there are 4 cells tied together creating a 12v batter
then there are 4 of these. Son in law had me use a 4s bms
w/1 lead for each bank.
All of the cells for the last year have individually tested between
3.2+ and 3.3 volts

All of the battery/system cables are either #2 or #4 Welding cable.
I have not set the parameters yet excepting for the dates and times.
I do not know the proper sequence for setting the parameters.
To date I have been using a Noco Genius charger that has only brought the
battery up to 13.4 volts, no matter how long I leave it on.
One or two solar panels have been tied in for little bits bringing
in 17 volts and 4-5 amps..
Until The scc quit I have been keeping a load on the 12v system getting to know it.
The lowest the battery voltage has gotten to is 12.4 volts per the MT50 meter.
Hope this helps.

 

[rickst29]

Remove all loads - this is about charging and not discharging. Just the SCC, the battery bank and ALL the Solar Panels. A "4S" BMS spread across 4 cells on each lead cannot be assured to bring all those cells to full and balanced charge (3.60). It will give up when the average looks good. If the BMS pushes all the way to 3.65, then one or even two of 4 cells may be overcharged and slightly damaged, others may be left slightly undercharged and out of balance. Maybe program your Tracer to "user" parameters like this:

Over Voltage Disconnect 14.7 V
Charging Limit Voltage 14.6 V
Over Voltage Reconnect 14.6 V
Equalize Charging Voltage shut off or 14.4 V
Boost Charging Voltage just 14.4V (others use higher Voltages to charge in slightly less time, but this is sufficient for your testing)
Float Charging Voltage 13.6 V
Boost Reconnect 13.4 V
Low Voltage Reconnect 10.9
Under Voltage Warning Reconnect Voltage 11.5
Under Voltage Warning 11.5
Low Voltage Disconnect 10.8
Discharging Limit Voltage 10.5
Equalize Duration 0 or set as low as possible
Boost Duration 120 minutes

Under good sunlight, this should try to charge maximum PV input power for up to 120 minutes, up to a maximum Charging Voltage of 14.5V (or 14.4V). At the end of 120 minutes, it will quit pushing so hard and fall into float, as long as battery Voltage is above 13.4V. Low-resistance LFP battery cells should still be accepting considerable input power in that State, as long as the sun is shining. And if battery Voltage falls below 13.4V, the controller should go back into Boost Charging mode - at up to 14.4V "Constant Voltage", for another 120 minutes.

Possible Noco "smart charger" issues are irrelevant: Don't even use it, if you want to test the Tracer SCC. And it's possible that your tiny and temporary "trials" of just one or two Solar Panels, bringing in less than 100 Watts, aren't going to prove anything if your daily loads suck out all the power which the panels can put into the batteries in their relatively few hours of sunlight. Your symptoms are exactly like high loads dragging your batteries down and into "excess discharge - low voltage" state, disconnecting the batteries from the Tracer.

We don't know whether to blame the Tracer until we test it with those loads removed. Please advise of your results (Solar day start and Solar Day end), for two sequential days of running it with no loads attached on the batteries.

 

[garyr]

Thanks I will try to set the parameters
Problem is though that the scc will not "turn on" the power to the load.
will work on parameters

 

[rickst29]

Gary, what will happen with my parameters is: the "load" will drag the batteries down to lower Voltage (below 13.4V "Boost Reconnect"), and then the SCC should try to go back to "Boost Mode" and charge as hard as it can, using up to 14.4V.

If your loads are much bigger than your Solar, then it is a losing proposition - the SCC can't keep the batteries at full charge, the load "drags down" more than the SCC can "boost up".

Your Load should be connected directly to the batteries, and not the SCC "load terminals". Those SCC terminals are only for very small loads, and should only be used when you want to utilize the programmable timers. If you want to quantify your "loads", then you should invest in a coulomb-counter meter, connected to the battery bus:

All "negative current", including the SCC terminal and the grounding connections for all loads, go through the coulomb counter shunt before being reaching the 4x4 battery "-" terminals. One small wire goes to any battery + lead. With that in place, you can measure all of your battery power (in and out) from everything together. Subtract any "charging" which is shown on the MT-50, and the remainder (a bigger NEGATIVE number) is the total of your other "loads".

 

[garyr]

Rick, Thanks so much! I have learned a lot through your tutelage.
The parameters are now set. Had to bounce around to get it to take them all. had
to incrementally set the under voltage warning reconnect voltage down to 11.6v It will not accept 11.5.
I thought that the bms ground was too small for the main system ground but could not find a definitive
answer so with all online information I ran the system/house ground through the bms
and in turn the scc. I maybe fried the output leg of the scc, although inspection revealed the 2 40 amp internal
fuses of the scc are fine with no visible damage to the circuit board.
From what I gather you are saying I should have trusted my gut from the beginning and just used the scc as a charger
for the battery coupled with the bms to oversee the batterys' condition only.
What I am powering is a 3/4 ton single rear tire mercedes van conversion. There are 10 LED house lights, 2 flourescent lights (never are all on at once,) a propane furnace, on demand water heater, 12 volt fridge and television and a cell phone signal enhancer that the jury is still out on.
Never is even half of it on at once. Oh the 3000 watt inverter is mainly for the microwave maybe 2 minutes once a day.
Playing with the battery system for the last year before hooking up the scc, it takes about 2-3 days for the battery to discharge from 13.4 volts to 12.2v.
I think the solar will keep up fine.
Most folks it seems just attach the pv panels to the roof. I am devising a raised platform that will both shade that portion of the roof and keep any panel heat up and away from the roof. I also have it in mind to hinge the bracket for adjustable uv capture.

 

[rickst29]

That microwave is a killer appliance, as follows: 1000 Watts (120-VAC) / 80% efficiency in the Inverter requires about 1250 watts from the DC side. That's about 100A continuous, after the Inverter has "warmed up" it's on board capacitors. That needs a big 12v power cord pair, with wire size AWG-1 at the bare minimum and only if the distance is less than 2 feet. Preferably something bigger than that such as AWG 2/0, which I use for my smaller "1500 Watt" Inverter supporting a smaller microwave (only 800 watts).

If the 12-volt fridge is using a Danfoss compressor, it's insignificant for instantaneous loads, although it might be consuming around 30Ah through each day. If the "12 volt fridge" is not a compressor model, then you really need to be using propane heat (and not the 12-volt heater coil). In "12v mode", a compressor fridge burns about 130 Watts, and has a much longer duty cycle. That alone can burn through about 100Ah every day, maybe even more.

12V "Grounding" follows the shortest (most efficient) connection to the battery "-" terminals, should not be going through the SCC except for "charge current" to and from the MPPT SCC charging circuit itself. The SCC should have been wired like a "just another small appliance", except that it adds power (rather than consuming it). It should never be subjected to anything bigger than the 40A for which it has been designed. Same rule applies on the "+12V" battery side of the SCC - it all needs to go as direct to the BMS and Battery as possible.

Your earlier "gut feeling" was good, I think.

 

[snoobler]

@rickst29 nice work getting it sorted.

In my experience, microwaves are WAY less efficient. A typical 1000W OUTPUT microwave pulls closer to 1600W AC INPUT and thus pulls even more from the battery when you factor inverter inefficiency.

When starting from scratch, the best option is a Panasonic inverter microwave. They aren't that much more efficient, BUT they truly run at lower power. Traditional microwave @ 50% power is still 100% power, 50% of the time. An inverter microwave actually uses less power continuously.