OK, so I think I have the conclusive evidence I needed to show they are just not compatible. I reinstalled my AGM battery (Chenged the RED wire to (-)) and hey presto everything works as it should. On loading the AGM the solar panels kick in and cover the demand. With them off and the engine running it takes all the current it needs from the alternator. Rather a lot of time went in to finding that out. Until my RENOGY DCDC charger arrives I'll reconnect the Li battery and see if I find any state of where the CTEC is happy to cut in. SOLVED!!!!!
CTEK D250SE Query (with Renogy battery)
- Thread starter YellowHound
- Start date
Update - Renogy and CTEK have the same wiring configuration. Uprated the fuses, swapped over the wires and hey presto, everything works as it should and of course with the BT dongle the Renogy tells me everything it is up to. On solar and Alternator it will give 25 amps from each. If you switch off the solar, it will give 50amps from the alternator along - that’s quick charging for a battery that will accept 100a. Job done.
Hi Blitz. CTEK still insist that it should work with Li battery, but it would not with my Renofy battery. Changing over to the Renogy charger (I think its on special offer too) with the Renolgy battery and everything was, and is still great. In respect of your cable you can set the maximum charge rate on the Renogy via the app. It's rated at 50Amps. If solar panels are connected then it splits this 50/50 between the solar input and alternator input - at 25A you can leave the cables as they are. If not using solar panels - or you have the ability to switch them off then 50A from the alternator is allowed, but you can still restrict the charge rate within the DC Home app to a lower value - so you do not need to change your cables. I have left my cables as they were but I did change the fuses to the recommended value of 60A.
id have another look at this. . .
if you have a 60A fuse protecting a 20A cable set. . . . . the 20A cable set will melt/catch fire before the 60A fuse blows. (in the event of an over current problem)
as you say you can "current limit" the renogy DC charger with the BT-2 adapter via the APP.
20,30,40A etc
if you have a 60A fuse protecting a 20A cable set. . . . . the 20A cable set will melt/catch fire before the 60A fuse blows. (in the event of an over current problem)
as you say you can "current limit" the renogy DC charger with the BT-2 adapter via the APP.
20,30,40A etc
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Thanks mate. Yes the ability to lower the amps or indeed leave the solar connected so only 25amps from the alternator solves the problem. A re wire with even thicker cables doesn't feel like fun. I had enough problems the first time.
The increased solar wattage is more important as the 300w Ctek is limiting. Obviously lithium battery compatability is necessary too. My batt is prob 3/4 years old so replacing with another lead isn't a good long term plan.
Thanks for your reply.
The increased solar wattage is more important as the 300w Ctek is limiting. Obviously lithium battery compatability is necessary too. My batt is prob 3/4 years old so replacing with another lead isn't a good long term plan.
Thanks for your reply.
you will need to set the current limiter in the DC charger to say 20A . . . ( to limit the system to 20A )
and not rely on the SOLAR input being detected.. . . ( ia at night time it will ignore the solar input and move to MAX current - ie 50A, unless you set the limitter . . . to 20A)
and even then you are reling on firmware programming and no blips.
its fine to use in the short term . . . . but i would not feel happy using a 50A charger untill i had a 50A cable/fuse set installed.
safety first right . .
What size CSA would the tails from the solar panels be to take 50A DC, as an ex Sparky I know that depending on the length of the run ie. more than a few metres you would be veering towards 16mm2 like the old 60A cutout meter tails so fatter than 0 guage?
I have the ctek 250se and was hoping to drop a lithium battery in on place of my AGM. If it doesn't work and I need a new DC to DC charger it's starting to get expensive
I know your pain lol. Renergys are on black Fri offer, so I'm looking now
OK
Looking at 3x 175w renogy rigid panels roof mounted, as the dimensions are a better fit. The 200w panels are too long for side ways fitting. Going to use uni rail bars running down and across the roof for a solid mounting frame. Rigid panels are cheaper and I don't need to worry about overheating.
Looking at 3x 175w renogy rigid panels roof mounted, as the dimensions are a better fit. The 200w panels are too long for side ways fitting. Going to use uni rail bars running down and across the roof for a solid mounting frame. Rigid panels are cheaper and I don't need to worry about overheating.
In my case the CTEK worked ok.... Just not optimal.
A lot of things effect the outcome like thickness of cable installed and the length... If.you get volt drop it will effect the charge of the battery..
www.t6forum.com
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A lot of things effect the outcome like thickness of cable installed and the length... If.you get volt drop it will effect the charge of the battery..
[Guide] DC-DC Charger (for leisure battery) -- How I Done It --
Thanks Lee. Or should I say Mr. Renogy! Been looking at your threads so will work out how to do it all now. Thanks bud.
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This is what I'm going to do on my camper but with the flexible panels, frustrating that the Renogy 200 watt panel is cheaper by £20 but at 3" narrower the 175 watt panels will just about squeeze in side by side on the pop top.
Back to the potential output currents involved and the distance to the seat base leisure battery/Mppt controler I figure you would need to run any extension leads back individually back from each panel otherwise paralleling them on the roof will need an hoofing great thick two core downlead?
