Ctek low output voltage from alternator

[PlowKing]

Hey gang, first post. Thanks for having me.

I have just installed a ctek with 100ah lithium battery but it's only charging at 13.7v

Using a multimeter while engine running;
At battery 14.7v
At ctek input 14.3v
Output of ctek 13.7v

Is this low?

Thanks

 

[ginkster]

How full is the leisure battery? The charge voltages drops off as it gets near fully charged. Is the CTEK on its lithium setting?

 

[PlowKing]

Battery is 13.36v when engine off and alternator disengaged. Yes, smart battery wire thing attached to "battery + out" bottom right.
Thanks for the reply

 

[Dellmassive]

Is it a ctek d250Se and the battery type select set to lithium?

What battery? .. any app or idea is state of charge?

 

[PlowKing]

Yes set to lithium, smart battery wire thing attached to "battery + out" bottom right.
Renogy 100ah LiFePO4, brand new, no app

Thanks

 

[roadtripper]

You should have TWO wires connected

One wire to select smart alternator and one wire to select the charging profile.

Do you have both connected and can you post a picture?

 

[ginkster]

You have 2 of the experts here now.

Does the charge voltage increase if you have a load on the battery (e.g. the fridge running)at the same time?

Over to Dellmassive and Roadtripper.

 

[PlowKing]

I thought the two wires were
Red to switched live - via piggy backed fuse
Black/red is battery selector?

Not best photo sorry. But the black/red wire is connected to "battery + out" on the bottom right of the unit

 

[PlowKing]

It seems to work perfectly other than the low voltage. Powers on etc and shuts off with the engine, lights as shown above when charging and nothing flashing.

Thanks for the help guys

 

[Dellmassive]

The Renogy App is called DC Home..

DC Home, bluetooth app, dchome | Renogy

Renogy DC Home APP is ready to Serve, are a new energy life new way hardware community app, where you can manage the hardware equipment in your RV and communicate with new energy people. You can use the Renogy DC Home App to configure, monitor, and diagnose selected Renogy DC Home compatible...

www.renogy.com

...
It's on Google and Apple.


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The smart version needs the bt2 adapter.

The other version has bt built in.




If you can connect....

You can see the batter voltage. SoC, Current in/out etc.

 

[roadtripper]

I would double check the black battery select one, maybe use the 12v input terminal.

The voltages you are seeing looks very much like the floating voltage of a normal lead acid profile - which is what you'd get if it was left disconnected.

 

[Dellmassive]

13.6v is normal for the battery as it's charging up.

You will only see 14.2v as it's 95% or more full.

It will take hours on the d250, it's about 25A max charge rate...so Will take a few hours to raise a new battery from 50% up to fully charged.

 

[roadtripper]

Bit of artificial brightening

 

[PlowKing]

I don't think this battery has BT built in
https://amzn.eu/d/bLfAz0K

Ok, maybe I'll swap the black/red wire over to the incoming battery feed.

Thanks

 

[PlowKing]

13.6v is normal for the battery as it's charging up.

You will only see 14.2v as it's 95% or more full.

It will take hours on the d250, it's about 25A max charge rate...so Will take a few hours to raise a new battery from 50% up to fully charged.

Ah ok, thanks. I assumed it would be similar to service battery and run at 14.2v ish

 

[Dellmassive]

Red to ign pos for smart alt.

And black to pos for lithium select.


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[roadtripper]

If this is literally the first charge then do as @Dellmassive suggests and give it a chance to charge up from shipping charge level.

If it doesn't rise in a reasonable length of time (3-4 hours) then double check the black charge profile setting wire.

 

[PlowKing]

Red to ign pos for smart alt.

And black to pos for lithium select.


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View attachment 227952

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I was confused by this before installation, did some research and saw this video where he seems to point to the battery + out. I'll try swapping it, thanks!

@ 2 minutes in;

 

[Dellmassive]

I was confused by this before installation, did some research and saw this video where he seems to point to the battery + out. I'll try swapping it, thanks!

@ 2 minutes in;

That vid...

He says both to pos..

One To ignition pos for smart.

And other pos for lithium select.

 

[PlowKing]

So, I have black to switch ign pos and other to the battery + output, bottom right.
Shall I try the incoming 12v instead of the output 12v? Or try leaving it to charge up fully first and see in a few days?