CTEK controller under hood overheating (1 Viewer)

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May 20, 2020
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LC100 - installed the Slee aux battery bracket, and an X2 Power (around 55ah) battery. CTEK DS250 charge controller. I mostly keep the ARB 50qt fridge running.

Issue came up while driving slowly on the beach that the charger was not delivering charge to the battery. We got back on the highway, stopped for gas, and when we continued on it started charging again.

The CTEK shuts down thermally at some point. Manual shows max ambient temp of 122 degrees F. I'm sure it gets higher than that under the hood in Texas driving slow...

I need to keep the battery under the hood, and move the charge controller inside the vehicle. The thing is this will add a LOT of extra wire runs between the alternator, charge controller, and aux battery.

Ideally the CTEK would go on the passenger side footwell, really close to the aux battery, but I hesitate to put it where it can be kicked.

Thoughts on placement, or do I just bite the bullet on wire runs and mount it accessible in the rear cargo area?
 

FrazzledHunter

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Is the CTEK stuff even designed to run under the hood? I don't think it is. I have a CTEK MULTI US 7002 charger that resembles your charger in terms of look and operating temperatures. Mine says in the manual the limits are Ambient Temperature -4°F to +122°F. I use it in the garage when I think the battery needs a lift or recondition.

The CTEK is good light duty stuff for use in the garage but it's hardly up to engine compartment duty AFAIK. It's meant to mount on the wall. Get a REDARC BCDC or stuff made by Victron to mount in the engine compartment. Their stuff will cost more but will save the aggravation of the wiring. I have a REDARC BCDC 1225D in the engine compartment charging my 2nd battery for a year now with no issues.
 

sdnative

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Can you mount it behind the grill forward of the radiator? It's only IP65 so it may be too exposed there.
 

spressomon

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FWIW, Victron Solar controllers are rated to 60ºC/140ºF but full output is only rated to 40ºC/104ºF. The other day I checked the output of my Victron 100/50 and almost no current was flowing from the Victron MPPT controller. The ambient air temp in the battery compartment was 105ºF. Once the ambient temp in the box went down to 100ºF, current started to flow from the controller to the battery (battery was still in the absorption phase...).
 

FrazzledHunter

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FWIW, Victron Solar controllers are rated to 60ºC/140ºF but full output is only rated to 40ºC/104ºF. The other day I checked the output of my Victron 100/50 and almost no current was flowing from the Victron MPPT controller. The ambient air temp in the battery compartment was 105ºF. Once the ambient temp in the box went down to 100ºF, current started to flow from the controller to the battery (battery was still in the absorption phase...).
I wasn't sure if OP was doing solar. The Victron Orion-Tr smart battery chargers have an operating range of -20 to +55°C (-4 to 131F) (derate 3% per °C above 40°C). That's not a huge difference - I'm surprised but I'll be using my 12-24 15 in the passenger cabin to charge a Yeti Goal Zero 1500X power station. My REDARC 1225D which has solar and charges my 2nd battery however, claims operating temps as -14° to +175°F (-10° to +80°C).
 
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I wasn't sure if OP was doing solar. The Victron Orion-Tr smart battery chargers have an operating range of -20 to +55°C (-4 to 131F) (derate 3% per °C above 40°C). That's not a huge difference - I'm surprised but I'll be using my 12-24 15 in the passenger cabin to charge a Yeti Goal Zero 1500X power station. My REDARC 1225D which has solar and charges my 2nd battery however, claims operating temps as -14° to +175°F (-10° to +80°C).
I am running solar, right now a 100 W portable (Rockpals), and may add a 100 W fixed on the roof. The CTEK works great when parked and adding in the portable angled to the sun.

BUT one more thing, the Redarc 1225D lists as suitable for battery banks form 75-200 AH. My little battery is about 55AH (limitations on size due to the Slee aux battery tray... unless I go with $$$ lithiums!!).
 

FrazzledHunter

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I am running solar, right now a 100 W portable (Rockpals), and may add a 100 W fixed on the roof. The CTEK works great when parked and adding in the portable angled to the sun.

BUT one more thing, the Redarc 1225D lists as suitable for battery banks form 75-200 AH. My little battery is about 55AH (limitations on size due to the Slee aux battery tray... unless I go with $$$ lithiums!!).
I really liked the REDARC.
It's one unit for charging 2nd battery via alternator & solar, has the highest heat operating range AFAIK and was reasonably priced.
I realize there are other options, just as good, involving separate chargers and MPPT controllers.

I'm wary of battery Ah ratings that don't say the 20 & 10 Ah values.
Per the advice of REDARC and from what I've seen others do I went with the REDARC 1225D on my Odyssey group 35 PC1400 which has a 20/10 hour Ah of 65 & 55 respectively. I was told by REDARC (I think it was them) that the 1225D was fine but the 1240D is too much for that battery as it could heat the battery too much when charging. I assume damaging heating would only occur if the battery were deeply discharged (perhaps repeatedly) and the 1240D REDARC therefore would be doing a LOT of charging.

My understanding is that Lithiums don't like engine compartment heat AT ALL.
However, heat issues can be resolved by judicious mounting of battery and other components.
For example I've seen stuff mounted in front of the radiator.

I used Slee's mount; the circled area in the picture is the Solar charging connection for my MERLIN XP170 panels.
The REDARC gets a lot of radiator fan blow-by which I guess helps in both cold and hot weather.
In any event, I've run down the 2nd battery pretty far a couple of times and haven't had a problem with anything in a year, knock on wood.
IMG_5005-640x360-2.jpg
 
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I really liked the REDARC.
It's one unit for charging 2nd battery via alternator & solar, has the highest heat operating range AFAIK and was reasonably priced.
I realize there are other options, just as good, involving separate chargers and MPPT controllers.

I'm wary of battery Ah ratings that don't say the 20 & 10 Ah values.
Per the advice of REDARC and from what I've seen others do I went with the REDARC 1225D on my Odyssey group 35 PC1400 which has a 20/10 hour Ah of 65 & 55 respectively. I was told by REDARC (I think it was them) that the 1224D was fine but the 1240D is too much for that battery as it could heat the battery too much when charging. I assume damaging heating would only occur if the battery were deeply discharged (perhaps repeatedly) and the 1240D REDARC therefore would be doing a LOT of charging.

My understanding is that Lithiums don't like engine compartment heat AT ALL.
However, heat issues can be resolved by judicious mounting of battery and other components.
For example I've seen stuff mounted in front of the radiator.

I used Slee's mount; the circled area in the picture is the Solar charging connection for my MERLIN XP170 panels.
The REDARC gets a lot of radiator fan blow-by which I guess helps in both cold and hot weather.
In any event, I've run down the 2nd battery pretty far a couple of times and haven't had a problem with anything in a year, knock on wood.
View attachment 2700764
Great input, thanks!
I've got a tech info req to Redarc and if they ok me on a small battery, I'll get moving on the 1225D, mounted forward the radiator. Then I can move the CTEK to the trailer to manage the charging there via solar. I suppose if I upgrade the alternator and run a heavy charge line all the way back I could charge the trailer battery as well.

This will give me room on the Slee mount also to put the air compressor under the hood (kid of pisses me off... I saved $$ by getting the Puma, and then upgraded that to a Viair... and now I'm going to do what I should have done and just get the damn ARB dual for under hood. It's about space in the cargo area...

While we are at it, what charge monitor are you using? I hooked up volt meters to the aux batteries and quickly noted this was a very weak solution. I put a Renogy shunt monitor in and am getting good data. That will probably move to the trailer also, so I'll need a SoC meter for the under-hood aux battery. What have you used?
 

FrazzledHunter

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Great input, thanks!
I've got a tech info req to Redarc and if they ok me on a small battery, I'll get moving on the 1225D, mounted forward the radiator. Then I can move the CTEK to the trailer to manage the charging there via solar. I suppose if I upgrade the alternator and run a heavy charge line all the way back I could charge the trailer battery as well.

This will give me room on the Slee mount also to put the air compressor under the hood (kid of pisses me off... I saved $$ by getting the Puma, and then upgraded that to a Viair... and now I'm going to do what I should have done and just get the damn ARB dual for under hood. It's about space in the cargo area...

While we are at it, what charge monitor are you using? I hooked up volt meters to the aux batteries and quickly noted this was a very weak solution. I put a Renogy shunt monitor in and am getting good data. That will probably move to the trailer also, so I'll need a SoC meter for the under-hood aux battery. What have you used?
Disclaimer: I'm not an expert on this. I did consult experts like REDARC, however. If I'm wrong about any of this I hope someone will correct me.

Note that the temperature rating on the REDARC is 14-175F.
It's the highest I've seen.
But you live in Texas and things are different weather-temp-wise than here in MD so mounting is now a question for you.

My power scenario is the REDARC charging the 2nd battery I mentioned and also a Goal Zero Yeti 1500X which will ride in the cabin. Both the REDARC and the 1500X can charge with the SAME Merlin XP170 solar panels. I have reasons for wanting all this power but that's off topic.

I'm not monitoring the charging of the 2nd battery connected to the REDARC other than to occasionally put a volt meter on it and watch the charging lights on the REDARC.

I suppose I could add power monitoring on as I'm really curious about power out of the alternator and from the REDARC to the 2nd battery.
  • I think I would use Victron Smart shunts for the monitoring.
  • The Yeti 1500X has a panel that displays power in and out - no extra monitoring need there.
But I'm really a little more concerned about total amps off the alternator because in addition to the REDARC I have an an Anderson SB-50 connector in the passenger cabin* fused at 50A. Connected to it (sometimes) will be my Victron 12/24 15 charger (output 15A @24V or 360W) to charge my Yeti 1500X via its 600W MPPT controller while on the move. That would make the input 30A @ 12V. So that's potentially an extra 30A+25A off the alternator worst case.

The 2nd battery is not a worry as it can be easily replaced; I'll just go buy another one if it fries LOL.
Maybe I'll get a bigger alternator. :cool:

*EDIT: the SB-50 is connected to the MAIN battery.
 
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Ordered Redarc BCDC1225D with mounting bracket and fuses.

Thanks for all the input!

I'll put the CTEK as charge control for the trailer.

One question I put to Redarc also, has anyone used the "Optional LED" listed on the wiring diagram for this controller? It looks like a remote indicator light, but I don't see any additional info on it either in the manual or on the Redarc site.
 

FrazzledHunter

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Ordered Redarc BCDC1225D with mounting bracket and fuses.

Thanks for all the input!

I'll put the CTEK as charge control for the trailer.

One question I put to Redarc also, has anyone used the "Optional LED" listed on the wiring diagram for this controller? It looks like a remote indicator light, but I don't see any additional info on it either in the manual or on the Redarc site.
Long story short I might have put an LED on the dash but never bothered. I may put one in at some point.

I reached out to REDARC to get one. It took 2 replies to sort it out. The first reply was that they don't sell 12V LED's. However I saw at these links regarding the LED's that said the LED's were not 12V at all, more like 7 volts.

BCDC1225D ... optional LED | REDARC Electronics - https://www.redarc.com.au/forum/discussion/2718/bcdc1225d-optional-led

Indicator led voltage on BCDC unit | REDARC Electronics - https://www.redarc.com.au/forum/discussion/786/indicator-led-voltage-on-bcdc-unit

So, confused I wrote them again about the correct LED to buy and here was the 2nd reply:

New customer message on June 22, 2020 at 12:19 pm
I’ve spoken at length with our tech support team and our head engineer for the BCDC products, the suggestion is the output is <9Volts and current limited to 6.2mA.

In some cases the resistors used on 12V rated LED’s aren’t specific enough to our requirements, so it seems we are generally suggesting the use of a standard 3V LED without a resistor to be the preferred method.

Something like this would be fine and I’m sure you’d be able to purchase from your local electronics store, with a nice small shroud/holder to fit in a spare switch panel.


A specific 12V LED with a wider voltage range would generally work ok, say 6V – 20V however not so easy to come by nowadays… or so it seems!
 

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