CTEK Chargers

[KING46Calais V]

True but lipo (lithium polymer) batteries used in rc cars are a completely different kettle of fish compared with lead acid batteries in cars, I actually have a fire proof bag for storing and charging my lipo batteries which is a common practice for rc…. The ctek smart chargers are fine to leave hooked up 24/7

Yes I have RC as well. I even thought of putting the unit into a battery bag while it was in use. I have gone away from bags now and use an old ammo tin after I saw a video of a 6S burn through a bag like it was paper

 

[KING46Calais V]

The CTEK chargers have had fire issues but that is only when bulk charging not when they're in maintenance mode.
I have a 10amp in my tool box at work and when it's in bulk which is 3 on the LED display it gets very hot.
When you sit on 7 it's the green LED it barely uses any power at all and is safe to keep connected.

But you only need to connect it every two weeks for a few hours and that will maintain the battery fine.
Also make sure the battery is very clean this will minimize any leakage.

That makes sense. I didn't take any notice of when these fires occurred but would assume it was when they were running at 100%.
I have noticed they do cool considerably once the battery reaches full charge.

 

[figjam]

Not CTEK, but I have 3 'Battery Fighters" @ 1.25amp which I have used for 6 > 7 years, and now have been in constant use on each car for the last year.

I connect them with the charger outside the engine bay, and with the bonnet down, but propped open about 100mm with a bit of wood.
Never had any problems (touch that bit of wood) with leaving them on constantly.
If the Terrorstory doesn't get used, or charged, for a couple of weeks, it is a very lazy starter.

 

[Angry8]

I have used them on all my motorcycles for years with no problem , they switch over to trickle when done.
I wouldn't have any charger closed under the bonnet . If you are really worried get the LED dongle $20 it has three lights green orange red and so you can easily see when you need to put the charger back on .......simple.

 

[vr304]

The CTEK chargers have had fire issues but that is only when bulk charging not when they're in maintenance mode.
I have a 10amp in my tool box at work and when it's in bulk which is 3 on the LED display it gets very hot.
When you sit on 7 it's the green LED it barely uses any power at all and is safe to keep connected.

But you only need to connect it every two weeks for a few hours and that will maintain the battery fine.
Also make sure the battery is very clean this will minimize any leakage.

Would have to think the ones that have a higher current (amp) rating would be more likely to cause issues with catching fire, more current equals more heat

 

[shane_3800]

Would have to think the ones that have a higher current (amp) rating would be more likely to cause issues with catching fire, more current equals more heat

Not necessarily, the workshop one is a 25amp and it has a fan so the build is different. Also a guy I work with has a 5amp and it's half the size.

Edit actually the workshop one is a PRO15-S so I assume it's 15amp.

 

[vr304]

Not necessarily, the workshop one is a 25amp and it has a fan so the build is different. Also a guy I work with has a 5amp and it's half the size.

Edit actually the workshop one is a PRO15-S so I assume it's 15amp.

Fair point mate I have the 5 amp ctek model and it gets a little bit hot but nothing excessive and as you say is quite small

 

[tml678]

The final stage of charging with the ctek is float mode. Essentially it turns itself off until the battery drops below 12.6(ish) volts, and then it gives a pulse to bump it back to full power again. It is fine to leave on 24/7

 

[Skylarking]

The CTEK chargers have had fire issues but that is only when bulk charging not when they're in maintenance mode...

While charging a 12v lead acid batteries is generally safe, CTEK do state the following in the owners manual safety section:

Always check that the charger has switched to STEP 7 before leaving the charger unattended​

and connected for long periods. If the charger has not switched to STEP 7 within​

50 hours, this is an indication of an error. Manually disconnect the charger.​

CTEK also states that the time taken to charge an empty battery to 80% charge as follows:

​

BATTERY SIZE (Ah)​	TIME TO 80% CHARGED​
2Ah​	2h​
8Ah​	8h​
20Ah​	4h​
60Ah​	12h​
110Ah​	26h​

Note I've diligently copied what seems to be errors from CTEK's manual... As shown above, an empty 110Ah battery can take 26 hours to bulk charge to 80%. Oddly the following page provides the charging programs and options combinations which shows the bulk charge (stage 3) is a maximum of 20 hours. Gotta love the clarity and error free owners manual that CTEK provide

As is, i think our commodore V8 batteries are 80Ah and as such shouldn't require more than 20 odd hours of bulk charge before they get to the float program as provided by the green LED stage 7. So just a short time of attended supervision needed

Sadly it takes a long 10 days before the charger goes to pulse program provided by stage 8 (which is annoyingly long)..

So in CTEKS mind, you must supervise the charging process by keeping an eye on the charge process until the stage 7 green LED has turned on, which can take up to 50 hrs... Year right...

Reality should be, if one is worried about setting fire to their house, then they should keep an eye on the battery temperature and that of the charger itself for up to 2 days and 2 nights to ensure they don't get too hot and bad things happen. How real is the probability of it burning down your house who really knows... But it's hardly a set and forget charger which is how it is marketed. The owners manual also contains inconsistencies and the whole thing seems a bit of a bait and switch with their safety warning stating supervision is required during bulk charge

As for pulse program (stage 8), it's unclear how low the battery voltage is allowed to go before the charger kicks in to top up the battery as CTEK doesn't mention such within their manual. In CTEK's video, it states the voltage can drop 5% before it's pulse charged

Frustratingly, a fully charged battery is nominally at 2.1V/cell = 12.6 volts and a 5% drop will see the voltage drop to 11.97V before the pulse charge kicks in. Such a low voltage is well within sulfation territory, so whats the go? What open circuit voltage are people seeing when in stage 8 pulse mode and when does the pulse charge actually kick in to pump up to the battery to 2.25V/cell or 13.6V which is 100% float charge level if that's what it actually does?

The lack of real detail in the manual is annoying as I've had other older brand float charger kill my batteries in the past. I simply want to make sure all is ok the CTEK charger and it works as it is meant to and my MSE battery wont sulfate and the charger wont set fire to my house (ok not reallty worried about a house fire as quality branded electronics are rather good thee days)...

 

[Skylarking]

The final stage of charging with the ctek is float mode. Essentially it turns itself off until the battery drops below 12.6(ish) volts, and then it gives a pulse to bump it back to full power again. It is fine to leave on 24/7

Stage 7 is float charge mode while stage 8 is pulse charge mode.

In float mode you should see the battery open circuit voltage held at 13.6V but while in pulse mode it slowly drops due to self discharge. It's not clear when the pulse charge kicks in to boost the battery voltage, nor is it clean what voltage it boosts it back up to? Any thoughts?