12v wiring bamboozlement

[WotEver]

2 minutes ago, BlueStringPudding said:

Yes. Both controllers are rated at 30A. 

One solar array is 390W and the other is 400W (latter has very long cables and are second hand so probably not putting owt like 400W into the controller). 

So both of those controllers could, on a cool and sunny day, each give their maximum output of 30A. The fuse therefore ought to be 60A or higher, assuming that the cabling is suitable for that current (the fuse is to protect the cable, not the controller). 16mm² would be the minimum you should be aiming for really from a volt-drop perspective, although you'd be okay with 8.5mm² from a current carrying perspective.  I've assumed a 5m run from controllers to batteries.  If the cable is any smaller than 8.5mm² then you'd need to downrate the fuse to suit.

[BlueStringPudding]

This morning is the first time that both MPPT controllers have been connected in daylight. I took multimeter readings at about 10am, so not in direct sunlight here yet but it is bright, and not too hot either. 

 

The SunSaver* controller measures as follows from its 400W array:

PV-in terminals 17.53v

Batt-out terminals 14.11v

LED appears to be indicating the controller is in Absorption Charge. (1 second green flashes) That sounds good to me.

 

The Victron controller measures as follows from its 390W array:

PV-in terminals 19.93v

Batt-out terminals 14.09v

The LED's on the Victron however appear to be indicating that, according to the manual, "the system is powered but there is insufficient power to start charging" (3 second blue flashes of the Bulk LED only). This was the same LED pattern last night before the panels were even connected to the controller - which made perfect sense then! It doesn't make sense now. I've read the manual repeatedly and can't understand why the LED indicator seems to be contradicting my voltage readings at the Victron controller itself.

 

The voltage across the busbars where both controllers combine is 14.09v.

 

The Victron is a BlueSolar MPPT Controller 100/30 without Bluetooth. I've looked at the Victron website and I can't find any relevant info. The manual only gives me a list of LED patterns to interpret. Does anyone know why the Victron LED indicator seems to be saying there's not enough "power" when the voltage at its PV-in terminal reads 19.93v (from a 390W max array)? And clearly the batteries are also fine. 

 

Is there something on the Victron controller that I need to tweak to change a setting? It's not clear from the manual because it has no diagram of the product's features/parts - it says it adjusts to the batteries automatically but as I've two controllers working together maybe that isn't the case in this situation? There may be a dial on it somewhere but I can't see it now it's mounted in the cupboard and all wired in. I've not knowingly changed any of its settings but it was secondhand so maybe it was originally set up for a different system...? I'm not sure that excuses it telling me there's a lack of power though, even if it was the case (just brain-storming supposition at the moment)  

Anyway, this blue flashing LED is bothering me. ? What are your thoughts, please?

 

[* The SunSaver I was calling the SunStar in earlier posts. Confusing the TriStar logo on it with the actual name of the controller. It's definitely a SunSaver MPPT controller]

Edited May 21, 2020 by BlueStringPudding

[WotEver]

4 minutes ago, BlueStringPudding said:

[* The SunSaver I was calling the SunStar in earlier posts. Confusing the TriStar logo on it with the actual name of the controller. It's definitely a SunStar MPPT controller]

Not SunSaver?

[BlueStringPudding]

15 minutes ago, WotEver said:

Not SunSaver?

Oh for feck's sake. Even predictive text is against me. Of course it's SunSaver ?

Well spotted.

[TheBiscuits]

18 minutes ago, BlueStringPudding said:

The LED's on the Victron however appear to be indicating that, according to the manual, "the system is powered but there is insufficient power to start charging" (3 second blue flashes of the Bulk LED only). This was the same LED pattern last night before the panels were even connected to the controller - which made perfect sense then! It doesn't make sense now. I've read the manual repeatedly and can't understand why the LED indicator seems to be contradicting my voltage readings at the Victron controller itself.

 

 

From the manual:

 

3.2 PV configuration

● The controller will operate only if the PV voltage exceeds battery voltage (Vbat).

● PV voltage must exceed Vbat + 5V for the controller to start. Thereafter minimum PV voltage is Vbat + 1V.

 

I suspect that if you throw a blanket over the panels connected to the TriSun StarSaver (  !!) the Victron will start charging, and stay charging when you remove the blanket.  It is possible that the SunSaver will then not start charging.

 

The problem with having the two controllers connected to the same system is that one of them starts charging, and the other one is seeing the charging voltage - 14.1V ish - and thinks the batteries are full, so does nothing.

 

If your batteries were less charged - you could also try switching on a large load to cause a voltage drop to fake this - you would probably see both controllers charging in bulk mode.

 

If your batteries were more charged, then only one of the two systems charging isn't a problem as the batteries can't take much current by then.  You seem to be at the exact opposite of the sweet spot!  Try the blanket thing or just wait and see if more sunshine on the panels starts the Victron charging. 

 

Do you know what the V_oc rating of the panels are?  If they are different, the higher ones might want to be connected to the Victron if they are not already.

[tree monkey]

The sunsaver one is

https://www.morningstarcorp.com/products/sunsaver-mppt/

 

[Jen-in-Wellies]

7 minutes ago, tree monkey said:

The sunsaver one is

https://www.morningstarcorp.com/products/sunsaver-mppt/

 

This is the model (SS-MPPT-15L)  I've had working on my boat for the last ten years. No idea if it plays well with other solar controllers as it has been the only one.

Jen

[BlueStringPudding]

4 minutes ago, TheBiscuits said:

 

 

From the manual:

 

3.2 PV configuration

● The controller will operate only if the PV voltage exceeds battery voltage (Vbat).

● PV voltage must exceed Vbat + 5V for the controller to start. Thereafter minimum PV voltage is Vbat + 1V.

 

I suspect that if you throw a blanket over the panels connected to the TriSun StarSaver (  !!) the Victron will start charging, and stay charging when you remove the blanket.  It is possible that the SunSaver will then not start charging.

 

The problem with having the two controllers connected to the same system is that one of them starts charging, and the other one is seeing the charging voltage - 14.1V ish - and thinks the batteries are full, so does nothing.

 

If your batteries were less charged - you could also try switching on a large load to cause a voltage drop to fake this - you would probably see both controllers charging in bulk mode.

 

If your batteries were more charged, then only one of the two systems charging isn't a problem as the batteries can't take much current by then.  You seem to be at the exact opposite of the sweet spot!  Try the blanket thing or just wait and see if more sunshine on the panels starts the Victron charging. 

 

Do you know what the V_oc rating of the panels are?  If they are different, the higher ones might want to be connected to the Victron if they are not already.

That's what I'm going to call it from now on ?

 

Thanks for the advice. The PV voltage does exceed battery voltage because even if there was no voltage drop in the cables, the batteries would be at 14.11v  maximum thanks to the SunSaver output, but the PV-in voltage at the Victron is 19.93v which exceeds the +5v criteria to start charging. Unless it's not the PV voltage that's relevant but the batt-out voltage at the Victron controller...?

 

I'm going to try a few things based on your advice:

 

1. Turn everything on indoors like the fridge, tele, lights and stereo - see if that creates enough draw to wake up the Victron.

 

2. Try the blanket thing once I have assistance from the beautiful, lovely Monkey Mcgee later.

 

In answer to your question, I don't know the V-squiggle rating of the panels. I'll try to find out. I don't want to switch the controllers over unless absolutely necessary because it means stripping and re-crimping the cable ends as the controllers have different terminals, plus I know I've had a working 390W/SunSaver array (half the current set-up) for a few years, I'm reluctant to feck that bit up.

 

[tree monkey]

1 minute ago, BlueStringPudding said:

 

 

2. Try the blanket thing once I have assistance from the beautiful, lovely Monkey Mcgee later.

 

 

 

I've always said it's a good thing you're too vain to wear glasses

[TheBiscuits]

2 minutes ago, BlueStringPudding said:

In answer to your question, I don't know the V-squiggle rating of the panels. I'll try to find out.

 

It's usually printed on the label on the back of the panels.

 

Take a pic of the whole labels on all the panels if you can - there will be loads of other useful bits on there for the techie geeks.

 

4 minutes ago, BlueStringPudding said:

That's what I'm going to call it from now on ?

 

I thought TriStar are a film studio ...  Morningstar make a TrakStar range of MPPT controllers

 

 

3 minutes ago, BlueStringPudding said:

2. Try the blanket thing once I have assistance from the beautiful, lovely Monkey Mcgee later.

 

Is Alan not available? 

 

 

 

 

[BlueStringPudding]

TriStar TrakStar SunStar SunSaver MorningStar... I give up! 

 

Top controller.

Bottom controller.

 

Done.

?

 

[TheBiscuits]

2 minutes ago, BlueStringPudding said:

TriStar TrakStar SunStar SunSaver MorningStar... I give up! 

 

Top controller.

Bottom controller.

 

Done.

?

 

 

Black and Blue?

 

Sunni and Vicky?

 

Working and Not Working?

 

 

 

 

[BlueStringPudding]

Well, turning on all the lights and appliances including the shower pump and flushing the loo for extra welly, made no difference to the Victron flashing light. 

It did however, stop the green flashing light on the SunSaver, suggesting it dropped out of Absorption mode. Now I've turned all the appliances off again (except the fridge) the SunSaver green light is flashing again so it's gone back to Absorption mode. Hmm... I've no idea what that tells me, if anything. 

 

 

[TheBiscuits]

2 minutes ago, BlueStringPudding said:

Well, turning on all the lights and appliances including the shower pump and flushing the loo for extra welly, made no difference to the Victron flashing light. 

It did however, stop the green flashing light on the SunSaver, suggesting it dropped out of Absorption mode. Now I've turned all the appliances off again (except the fridge) the SunSaver green light is flashing again so it's gone back to Absorption mode. Hmm... I've no idea what that tells me, if anything. 

 

 

 

Your batteries are too charged for it to have worked, which is good but not very helpful.

 

Do the blanket thing later and see what happens - it can't harm anything, it's just like it going dark.

[tree monkey]

3 minutes ago, TheBiscuits said:

 

 

Do the blanket thing later and see what happens - it can't harm anything, it's just like it going dark.

No it's not cause I won't be asleep

[BlueStringPudding]

A parallel thought...

("Are you pondering what I'm pondering, Brain?")

 

If the Victron thinks that "the system is powered but there is insufficient power to start charging" then why has it converted the 19.93v PV input to 14.09v output? Or has it not converted it but instead the Victron Batt-out terminals are just showing what the SunSaver is putting into the busbars?

[TheBiscuits]

1 minute ago, BlueStringPudding said:

A parallel thought...

("Are you pondering what I'm pondering, Brain?")

 

If the Victron thinks that "the system is powered but there is insufficient power to start charging" then why has it converted the 19.93v PV input to 14.09v output? Or has it not converted it but instead the Victron Batt-out terminals are just showing what the SunSaver is putting into the busbars?

 

Yes, that's what I think is happening, and I am wondering if the open-circuit voltage on Blue Vicky's panels is 20V ...

 

 

[TheBiscuits]

 

I thought this topic seemed familiar.

 

It's nearly a year since these were supposed to be fitted ... and over a year since you asked about this exact problem!

 

 

[BlueStringPudding]

1 minute ago, TheBiscuits said:

 

I thought this topic seemed familiar.

 

It's nearly a year since these were supposed to be fitted ... and over a year since you asked about this exact problem!

 

 

Yup. My own energy is vastly more limited than that of a SunStarMorningStarSaverStarTrekTrakStar controller.

I did all the indoor wiring last summer from the advice of the good people of this forum. The second solar array finally went on the roof a week or two ago ready to plug in - or so I thought.

 

In the interim, I wrestled a highly explosive gallbladder to the ground. Other hobbies include enjoying ongoing all-purpose kickings from my immune system, and being horizontal. So my days are quite fully occupied.

 

As a rule, I like to function from the bottom rung of Maslow's Hierarchy of Need, I fit in well there, with Boat Jobs not even in the same pyramid. Boat Jobs have got their own sarcophagus somewhere near the temple of doom, strictly for occasional day-trips and sightseeing tours between snoozes.

[TheBiscuits]

1 minute ago, BlueStringPudding said:

In the interim, I wrestled a highly explosive gallbladder to the ground. Other hobbies include enjoying ongoing all-purpose kickings from my immune system, and being horizontal. So my days are quite fully occupied.

 

Fair enough.  What you seem to be saying is you were grinding organs all year, so what you need is the other (in)famous team member to do the lifting. 

 

[BlueStringPudding]

Spot on

 

On the subject of lifting, I've just attempted to look under the Victron's solar panels. Can't see any labels as such, unless they're tiny and tucked away somewhere not obvious. All I can find that might be relevant is what's moulded into the black box on the back of the three panels. I can barely make out what it says so I've lowered the contrast if that helps, but I don't know if it answers your question about the open circuit voltage? I don't know what the symbols mean. Could be no bleach, cool tumble dry, do not dry clean for all I know

[Alan de Enfield]

7 minutes ago, BlueStringPudding said:

I don't know what the symbols mean. Could be no bleach, cool tumble dry, do not dry clean for all I know

Simply means  "Do Not Use On A Boat"

[TheBiscuits]

5 minutes ago, BlueStringPudding said:

I've just attempted to look under the Victron's solar panels. Can't see any labels as such, unless they're tiny and tucked away somewhere not obvious. All I can find that might be relevant is what's moulded into the black box on the back of the three panels.

 

Sadly not.  They are usually huge things stuck directly to the back of the cells and look a bit like this one:

 

 

If these are the panels you got last year, I would have expected to see a much higher open circuit voltage than 20V from the three of them in series, or are they wired in parallel?

[BlueStringPudding]

14 minutes ago, TheBiscuits said:

 

Sadly not.  They are usually huge things stuck directly to the back of the cells and look a bit like this one:

 

 

If these are the panels you got last year, I would have expected to see a much higher open circuit voltage than 20V from the three of them in series, or are they wired in parallel?

They're in parallel. 

 

And lo! Did the beautiful lovely Monkey McGee arriveth, and did lift of the solar panels more than my earlier feeble few inches, and verily did he discover the label of important stuff.

 

So bearing in mind there are three of these in parallel, what does that open circuit voltage (or any of the other numbers) mean in relation to resolving my annoying blue flashing light problem, please?

[TheBiscuits]

5 minutes ago, BlueStringPudding said:

So bearing in mind there are three of these in parallel, what does that open circuit voltage (or any of the other numbers) mean in relation to resolving my annoying blue flashing light problem, please?

 

Again from the manual:

 

12V battery and mono- or polycristalline panels

● Minimum number of cells in series: 36 (12V panel).

● Recommended number of cells for highest controller efficiency: 72 (2x 12V panel in series or 1x 24V panel).

● Maximum: 144 cells (4x 12V or 2x 24V panel in series).

 

So if you have three panels in series your controller will prefer it, be more efficient and your PV voltage will be around 60V so you won't be getting this "is 19V exactly 5V above 14V" nonsense.

 

I'm not going to suggest that you put two panels in parallel and the third in series to give boosted current at the ideal voltage because that would be heresy ...

 

Do the blanket-over-Sunni's-panels test first if you haven't already, so we can rule out any bad connections on the new PV cables to Blue Vicky.