Victron MPPT 15/75 Controller - settings issues

[Enginenumber]

Hi there all,
I have had a few goes trying to get this victron mppt 15/75 solar controller to work properly.(160ah winston cells, bmv 700 , wireless dongle for iphone, solar 240w)
Its definately an operator problem, me I think!

Read through the manual , watched videos, went through trouble shooting in manual again, contacted victron via email, who wont provide any advice either or technical support on the product.( sales people). Not received reply from the company where it was purchased either.

I also dont understand how this this operates , or how the settings work. I have got most of the settings off the forums in bits and peices , but , seems to make it do strange things.
From what I understand the controller needs bulk charge only , then cuts off at set voltage piont. Sounds easy , but I am unable to acheive this due to lack of understanding.

I switched off the default settings and tried adjusting a few settings , but no luck.

Now the controller charges on bulk till 11am approx , then goes onto what looks like a float charge at about 13.1v without going any higher on the charging.
At 11am , I thought the controller would of still been pumping 8-10amp into the battery still at that time. It just shows about .2 of an amp. Also the % on the BMV has gone back to 0% when there is 13.1v in the battery. There seems to be an V"!" which wasnt there when it was first conected. Unsure if I need to get some sort of computer software or something to get into more settings or if the ones I have are not right.

Hoping there is a few people who have set one up and got it working ok for lithium battery charging, and can steer us in the right direction as to what to do.
I am not a very computer smart either,especially with the settings or how this regulator works.

I can post up the settings I currently have here on the regulator,if someone wants me to as it may help solve it pretty quick.

Any help would be greatly appreciated.

Enginenumber

[jon_d]

Contact Julian on Aussie Motor Home forum.

I think he uses the Victron and know how to program it.

[Barboots]

Engine#, if your BMV shows 0% at any time (when you have a reasonably charged battery pack) it is programmed or installed wrong. My suggestion is to sort out the BMV settings first... and I'll dob in Mr T1 as the man for the job. [emoji6]

Out of interest, do you have a dependable multimeter? It would be worth connecting it to the lithium pack to ensure that you are not hurting it with the way things are programmed or set-up.

Cheers, Steve

[BruceS]

Enginenumber do you have a Christian name?

Have you gone right through the included setup details in the BMV?
Is it a 700 or a 702?
It's possible you have either a faulty connection or the network cable has dropped out of the gauge or the other end?

[Newcastle George]

Engine#,

Do you have the small manual for the BMV-700?

George

[Enginenumber]

Hi all,
to make it easier I will post up all the known settings I have below.
The guage still reads and the cable is fine. The manual for the mppt 75/15 is small , about 70mm by 60mm in size and not many pages in english. Also have the BMV 700 and manual.

I know when I first started it up there was an option for different charging alogerithym set ups, but I dont know how to get into that again or if anything needs changing there?
These settings are a bit all over the place , as I have no idea or understanding of it at all, and was just getting bits and bobs off internet, which may be questionable at times.

MPPT 75/15 settings

Battery Voltage 12v
Max current charge 15amp
Use default charge settings OFF
Charger ON
Absorption Voltage 14.20v
Absorption Time 06.00
Float Voltage 13.60v
Equalization Voltage 12.20v
Auto Equalization Voltage OFF
Temperature Compensation OFF
Load Operation Mode Always OFF
Street Light Function Off

BMV 700 Settings

Battery Settings
Capacity 160ah
Charged Voltage 13.8v
Tail Current 4.00%
Charge Detection time 3m
Pheukert Exponent 1.00
Charged Efficiency Factor 97%
Current Threshold 0.10A
Time to Go Averaging 3m

Relay Settings
Relay Mode Default
Invert Relay On
Min Closed Time 1m
Relay Off Delay 1m
Low Soc Relay 20%
Clear Low SOC Relay 21%
Low Voltage Relay 12.0v
Clear Low Voltage Relay 12.1v
High Voltage Relay 14.4v
Clear High Voltage Relay 14.2v

Alarm Settings

Alarm Buzzer ON
Low SOC Alarm 30%
Clear Low SOC Alarm 31%
High Voltage Alarm 14.6v
Clear High Voltage Alarm 14.4v

Hopefully that will make it pretty clear to see whats out of wack.
Regards,
Aido

[Newcastle George]

Aido,

Your mppt settings show an equalisation voltage of 12.2 which seems strange to me but I do not have lithiums or an mppt controller. Having Auto Equalisation Voltage set to OFF may mean that the 12.2 setting doesn't matter.

Can I suggest disconnecting and reconnecting the fuse to the BMV then pressing and holding for 3 seconds both Setup and Select. This will restore the factory settings and you can start again from there.

Once you have done this the relay settings will be the default ones which will differ from those shown above.

There is further info regarding settings for lithiums in section 5, page 35 of the manual.

George

[T1 Terry]

Hi all,
to make it easier I will post up all the known settings I have below.
The guage still reads and the cable is fine. The manual for the mppt 75/15 is small , about 70mm by 60mm in size and not many pages in english. Also have the BMV 700 and manual.

I know when I first started it up there was an option for different charging alogerithym set ups, but I dont know how to get into that again or if anything needs changing there?
These settings are a bit all over the place , as I have no idea or understanding of it at all, and was just getting bits and bobs off internet, which may be questionable at times.

MPPT 75/15 settings

Battery Voltage 12v
Max current charge 15amp
Use default charge settings OFF
Charger ON
Absorption Voltage 14.20v
Absorption Time 06.00
Float Voltage 13.60v
Equalization Voltage 12.20v
Auto Equalization Voltage OFF
Temperature Compensation OFF
Load Operation Mode Always OFF
Street Light Function Off

BMV 700 Settings

Battery Settings
Capacity 160ah
Charged Voltage 13.8v 13.9v
Tail Current 4.00% 1% (1.6 amps)
Charge Detection time 3m 1 min
Pheukert Exponent 1.00
Charged Efficiency Factor 97% 100% (it's actually 99.98% but the unit can only be adjust in 1% internals)
Current Threshold 0.10A 0.05amps (otherwise it will not record the small drains and upset the SOC over time)
Time to Go Averaging 3m (choose what ever you like, I generally turn it off as it is a useless function as the draw is never constant)

Relay Settings
Relay Mode Default
Invert Relay On
Min Closed Time 1m 0 min
Relay Off Delay 1m 0 min
Low Soc Relay 20% 5%
Clear Low SOC Relay 21% 10%
Low Voltage Relay 12.0v 11.8v
Clear Low Voltage Relay 12.1v
High Voltage Relay 14.4v 14.6v
Clear High Voltage Relay 14.2v 14.4v

Alarm Settings (The idea is to have an alarm warning before the relay forces a disconnect, so the alarm settings are should give enough warning time to sort the problem before a disconnect.)
Alarm Buzzer ON
Low SOC Alarm 30% 20%
Clear Low SOC Alarm 31% 22%
High Voltage Alarm 14.6v 14.4v
Clear High Voltage Alarm 14.4v 14.2v

Hopefully that will make it pretty clear to see whats out of wack.
Regards,
Aido

Hi Aido, to make it easier I will add the correct settings for the Victron BMV beside the settings you have now. As for the Victron 75/15 MPPT, after many battles and it winning all of them I gave up. I did talk with Julian at the last Taggerty get together and he gave me a number of links that contain information on how to get these things to work using the 700BMV as the voltage sensor and also how to get the b**** things to work together, cause in their natural state they consider every other charging source the enemy and simply will not play with them at all.
So, the first question, do you have any other charger connected and running on the battery pack? If you do then that is why it won't do any of the things the glossy pamphlet claims, they have to be the only charging source or they pack up their bat and ball and go home to sulk.

Next issue is their ability to read actual battery voltage, it is virtually non existent, it reads the voltage it sees on the cables it uses to charge the battery. This means any resistance what so ever on that circuit will cause the controller to read a higher voltage than the real battery voltage, once it reads a voltage it doesn't like it simply shuts down. Check every connection along these cables, use Midi fuses rather than circuit breakers because these have the least voltage drop across the cable. Even though you are only trying to pump 15 amps max down these cables, use 6 B&S cable to minimise the voltage drop and use quality connectors that require a hydraulic crimper, or do a really good soldering job to attach the connector to the cable. Forget about using those yellow banded self insulated crimp terminals, I'm sure they were designed by auto electricians to make sure they got the job of fixing it after a DIY attempt. If you have to use one of these, remove the insulated plastic band, open up the section where the cable is meant to go so the cable will actually fit in there, now crimp the connector over the cable and solder the joint, then finish off with a bit of heat shrink.
If you can find the correct path to adjust the return to boost/bulk charging mode, set it to 13.7v, at least that way when it spits the dummy that setting should force it to start working again.
Next, set the float voltage to 13.8v, it won't ever reach that because of the issue with reading its voltage from the charging cables, as soon as it starts charging at all the voltage will climb above 13.8v and the unit will again spit the dummy.
Next, drop the absorption time to 0.5hrs or you will have a very pregnant and rather expensive door stop rather than a battery pack. 14.2v allowing for the incorrect reading caused by the charging cables will probably be around 14v or less but it will creep up to 14.2v over time and this is way to high to expect the cells to remain in a close voltage group. 14.2v in a perfectly balanced battery pack is 3.55v per cell or 1v full voltage above the fully charged voltage and the cell is in the run away voltage zone. Unlike lead acid cells, when a lithium cell is full it is actually full but there is no guarantee the level is the same in each cell because voltage is not related to just how full it is, except when it is absolutely full or absolutely empty. Think of it as a beer glass that you can't see through. Using this analogy, first off you have a head on the beer, then at 3.45v rested the glass now has all the head just above the top rim of the glass, just the surface tension is holding it together. As soon as you try to add more beer it will split over the side of the glass but until you reach that point you do not know how much of the beer is head. Any voltage above 3.45v rested in any cell will potentially have the head on the beer running down the side of the glass, or, the cell voltage running away to the cell damage zone. The longer the cell is held above 3.6v the greater the damage...... or the more beer running across the floor If you are not monitoring cell voltages so you can stop charging if a cell reaches 3.6v you are playing Russian roulette with a rather expensive battery.

[Enginenumber]

Ok,
thanks guys , been bit lost with it all,and impatience, later today I will go over the whole thing again and set the recccommended parameters and check out the mentioned items.
Like the beer example ,thanks Terry, I can relate to that alright. And yes , I better sort it out befores I wreck it. I havent given up yet.
Will let you know how it goes in the following days.

Cheers,
Aido.

[Enginenumber]

Back again,
had some pretty clouded few days so was slow testing battery some.

The solar regulator is the only charging source for the battery. Isolated the pack from any current draw also.

I have bypassed the 15 amp breaker and wiring on the charging circuit atm. Put some pretty heavy wire from regulator directly to battery terminal ( 400MM LONG) Not very much voltage drop now from reg. to battery terminals.

Disconnected the BMV 700 for the moment, removed the fuse and comms cable so it doesnt do anything hopefully and interfer.( Have changed the settings in BMV700 as reccommended above also)

Could not work out how to get into the- "find the correct path to adjust the return to boost/bulk charging mode, set it to 13.7v".

Not sure if I can get into all the settings on the regulator with just the wireless dongle / phone.
Maybe need special download software or something to do that?

Regulator now stays on bulk charge all day which is good.

Regulator Settings now-
Use default settings - off
Charger on
Absortion voltage 14.20v
Absortion time 00.50
Float Voltage 13.80v
Equalization 12.20v
Auto Equalization OFF
Temp Compensation OFF

Regulator readings today- Part cloudy
7.15am 13.25v 1.9 amps
12pm 13.40v 6 amps
2.45pm 13.46v 7.9 amps
4.30 pm 13.40v 1.9 amps

13.46v is the max reading at the regulator today. So that is getting better, I would of thought the panels/regulator would of completely charged the battery today, starting at soc 13.25v this morning.

Will see if it continues charging to full tommorrow and will see.

Aido.