Alternator light flashing on ctek d250se after adding solar panel

Hamjamham

New Member
Hi folks.

First Post, I've been scouring the forums/internet but can't find my specific problem.

I've had a ctek d250se on my van for about a year all running great. I finally added a renogy 175w flexible solar panel to my van yesterday and hooked it up to the ctek today. Connected positive to solar input and negative to the negative terminal on the ctek.

All seemed to be running fine, especially when the engine is on - solid solar light (when it's light out), solid alternator light and solid leisure battery light + solid green power light.

Since adding the solar panel and when the engine is off and the van is locked, I can see green power light on (normal) but the alternator light flashing away. The battery light has switched off which is semi reassuring as it doesn't look like its draining the starter, but I've never noticed the alternator light flashing when the van has been locked for a while.

There's no fault light, just the alternator pulsing away. Any ideas? The manual doesn't show what this light configuration means, nor have I managed to find anything online.

Thanks in advance if anyone can help me out!
 
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I don’t have the ctek manual handy, but isn’t this the ctek pulse charging the starter battery - if the leisure battery is fully charged, it pulses the starter battery every few seconds to charges it. This is what mine does.
The VW smart alternator deliberately doesn’t fully charge the starter battery, so there’s always some charging that the ctek+ solar panel can do after you’ve driven the van

Simon
 
I don’t have the ctek manual handy, but isn’t this the ctek pulse charging the starter battery - if the leisure battery is fully charged, it pulses the starter battery every few seconds to charges it. This is what mine does.
The VW smart alternator deliberately doesn’t fully charge the starter battery, so there’s always some charging that the ctek+ solar panel can do after you’ve driven the van

Simon

Thanks for your reply. I wondered if it was that but I've never seen it before installing the solar. I often fully charge the leisure battery if via the mains if its been sat around not in use for a little bit and haven't seen that type of flashing before.

I went out and checked last night, solar was off as it was dark, but the alternator light still flashing away. I've got some more bits to do on the van today so I'll monitor it and see if anything changes.

Also, the voltmeter on the switchboard I've got is locked at 13.6 or 13.7 now which I usually only see whilst driving. Guessing that could be the solar panels though.
 
I have read within this forum that the ctek d250se does not take solar panels as big as this renogy 175w.
The Ctek will only take up to 23VOC this panel is 23.9v.
Not sure if I am right it was only what I came across whilst doing my research.
 
Couple of quotes regarding CTEK limitations. If you search there is more information on this subject.
Thanks. I'd looked at it but it has a OC voltage of 26.8 where the Ctek will only take up to 23VOC. I'd have to go down to a 150watts in their range to meet the parameters and given half a chance I'd rather not do that.
Not with this particular panel no. The VOC is 23.9V which exceeds the CTEK limit. I understand if you exceed the limit on a CTEK it goes pop. I changed my CTEK for a Renogy which has a VOC limit of 25V and which also shuts down if the voltage goes over 25.5V (instead of going pop).
Photonic universe do a smaller panel at 130Watts which does sit inside the CTEK limits. I’m sure there are others as well. Just look to ensure the VOC is less than 23V.
 


As an FYI in case this helps anyone. I emailed CTEK support and got the below response regarding this issue (which hasn't resurfaced for me by the way)

Flashing lights does not generally mean that the charger is broken. This explanation is also if green is steady and the orange light is flashing.


It means that there is a bad connection between the charger and the battery, and that can be
1. Visible - like broken leads, dirty battery poles, bad connection when charging via chassis, cable that has become detached from the clamp/eyelet, quick connector that is not accordingly fixed together.

2. not visible, - Sulphation problems, often due to deep discharge or long time with low charge. A sulphated battery has a layer of insulating lead sulphate on the inside. It does not cover the inside fully as you can still detect voltage across the battery. This kind of bad contact is inside the battery, and the charger cannot start charging.


In both cases the charger does attempts to reach the goal, by sending rapid peaks of tension, pulses of energy, until the battery starts to accept the charge. That is the flickering.


What to do?

1. Move the connections a little. Check that the quick connector is properly assembled. Check inside the connectors if the pins are OK. Check all visible possibilities. If connection is established, the charging indication light will be steadily lit.

2.Sulphated battery. Leave the charger connected for maximum 24 hours. If it has not been able to penetrate the sulphate layer after that, the battery is most probably in very bad shape and it might to be best to consider a replacement . If the yellow or green lamp lights steadily, the charger has activated the battery and it will probably work, but it is nevertheless soon at the end of its service life.. Let it charge for a couple of days to boost the power, while being aware at the same time that the battery will soon be dead. There are coarse sulphate crystals which no charger in the world can break down.



The flashing might also be a fault in battery cell if the flashing appears after some hours of charging.

If the battery started charging in the correct way, with the orange lamp, and then starts flashing after a while, this is due to a break somewhere. The easiest explanation is that the connection has simply fallen off, but it could also be a break inside the battery.



If the charger continues to flash no matter what battery you connect it to, it obviously has developed a fault.
 
Well, that's not good. Obviously not paying attention to the important bits, doh. Saw that the ctek could handle higher wattage and thought I was good to go.

Yep ,seen those pages in the manual but what I'm describing isn't in there. I've got no fault light just a flashing alternator light when the engine is off. Battery has never been drained or gone long periods without being topped up. The flashing alternator has only appeared since plugging in the solar panel.

Looks like I may need to add yet another box (mppt) and take that off the d250se then as I can't return the label now as its stuck to my roof.

I'll grab some pictures shortly!

Thanks all for the input!
 
try disconnecting the panel,

then a reset on the CTEK ( carfully remove the cables so it powers down)

then reconnect the ctek leaving the panel disconnected.

check and test if its ok and working.

if it is all ok , , , , try covering half the panel with a blanket then reconect the panel to the ctek and test. (the blanket will massivly reduce the panel output for testing)

check and test if its ok and working.

..


post some pics for us to see.


...


have a look at the Victron SMART SOLAR 75/15 MPPT that will work great with your setup

upto 75v VOC so you can add extra mobile panels in future

and up to 15A charge rate,

and has a load output too.



note the BLUE SOLAR - not bluetooth

SMART SOLAR with blue tooth.




1620036970505.png
 
Yep, think I'm going to get one ordered just now. So annoyed with myself, I purposefully got the ctek so I didn't need to get a separate one and got greedy. Could've saved myself £250 by just getting a 100w panel. You live, you learn.
 
It sounds to me like what you are seeing is the starter battery being pulse charged by leisure battery. The CTEK only does this if there is a solar panel connected so you won’t have seen it before adding the solar. The CTEK max VoC is 23V and it looks like your panel is above this, however, it is unlikely this is the issue. If the VoC is exceeded, the CTEK goes pop and you would not see any charging from solar at all (Possibly also from alternator).

I would suggest adding some load to your leisure battery to discharge it a bit (e.g. a fridge or coolbox) then see what happens. Once the charge has dropped a bit, I would expect to see solar and battery LEDs lit to show it is charging from solar (it sounds like it is fully charged so it probably isn’t doing this right now). Then once the leisure battery is fully charged, it will likely revert to what it is doing now.

If you have a battery monitor on your starter battery and can show us a graph that would help. If you don’t, well worth the £20 or so. I have one on both batteries and they are very useful when looking at issues such as this.
 
Yep, think I'm going to get one ordered just now. So annoyed with myself, I purposefully got the ctek so I didn't need to get a separate one and got greedy. Could've saved myself £250 by just getting a 100w panel. You live, you learn.
I did the same thing, didn’t research enough about the limitations, I fitted my solar. In the winter so the ctec survived, I’ve fitted a solar technology Bluetooth mppt regulater which charges both the batteries
 
It sounds to me like what you are seeing is the starter battery being pulse charged by leisure battery. The CTEK only does this if there is a solar panel connected so you won’t have seen it before adding the solar. The CTEK max VoC is 23V and it looks like your panel is above this, however, it is unlikely this is the issue. If the VoC is exceeded, the CTEK goes pop and you would not see any charging from solar at all (Possibly also from alternator).

I would suggest adding some load to your leisure battery to discharge it a bit (e.g. a fridge or coolbox) then see what happens. Once the charge has dropped a bit, I would expect to see solar and battery LEDs lit to show it is charging from solar (it sounds like it is fully charged so it probably isn’t doing this right now). Then once the leisure battery is fully charged, it will likely revert to what it is doing now.

If you have a battery monitor on your starter battery and can show us a graph that would help. If you don’t, well worth the £20 or so. I have one on both batteries and they are very useful when looking at issues such as this.

Good shout, I'll have a look into the monitors.

I definitely don't want my ctek going POP so I've ordered a victron smart solar 75/15 which should arrive tomorrow.

I've disconnected the solar from the ctek now and the lights are back to what I'm used to so I'm happy with that - I'll keep this just for the dc-dc which I've been very happy with so far. Should be a fairly quick job connecting the victron tomorrow then hopefully I'll be good to go if we get some sunshine! Lesson learnt and at least I'm in better standing for the future now.
 
Good shout, I'll have a look into the monitors.

I definitely don't want my ctek going POP so I've ordered a victron smart solar 75/15 which should arrive tomorrow.

I've disconnected the solar from the ctek now and the lights are back to what I'm used to so I'm happy with that - I'll keep this just for the dc-dc which I've been very happy with so far. Should be a fairly quick job connecting the victron tomorrow then hopefully I'll be good to go if we get some sunshine! Lesson learnt and at least I'm in better standing for the future now.
You could pop a smaller panel up to support the starter battery and use the ctek still surely that would be ok, I don’t pretend to know what I’m on about on solar I’m pretty much yeah whatever @Dellmassive said
 
You could pop a smaller panel up to support the starter battery and use the ctek still surely that would be ok, I don’t pretend to know what I’m on about on solar I’m pretty much yeah whatever @Dellmassive said

That's a good shout actually, not had any issues with the starter as yet but knowing that it's getting some extra juice could be worthwhile.
 
If your leaving it in the circuit as in the ctek I would put a small panel on it and connect it in that way if your running a separate mppt with the larger panel when the leisure is charged then the one on the ctek should charge the van, am I right or have I made that up in my head someone should be along to say yes or no
 
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My Ctek is doing the same and I’m not too worried about it. I had the solar panel connected up to the leisure battery before I sorted the piggy back fuse holder in order to get the starter battery working. I was getting a solid amber on the solar and leisure battery, showing the panel was charging the leisure battery. Since fitting the piggy back fuse and connecting the starter battery I now have a solid solar and pulsing starter battery light. Panel is 200w but only 22.7VOC so within the limit for the charger. When I turn on the ignition the A light stays solid so it all seems ok to me.
 
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