Ctek Smartpass 120

col661

Member
T6 Pro
Hi all. I'm just planning out my electrics and will be purchasing the CTEK D250SA to power a 110Ah battery under the drivers captain seat. I'll also be mounting 2x100w flexible solar panels on the roof to utilise the CTEKS's direct solar input for off grid camping. Think I have all that element in hand but I see CTEK do a Smartpass device that can also back charge the starter battery and prevent a total discharge of the leisure.

I was considering this but not sure if there will be space to mount both the D250SA and Smartpass under the seat with the battery. I also have to ask, is it worth is as its not cheap.

Has anyone else produced a similar setup and installed all under a single captains chair?

Thanks
 
not related to the smartpass but check the CTEK250SA can handle 2 x 100w panels mine is running 1 120w and that is pretty much its limit for v o/c
 
Looks like the Solar input of the D250SA is 23V MAX VOC

so you could run 2x 100w panels in parallel "provided that the panels VOC is LESS THAN 23V"

so if your panel was 100W 19V VOC with a ISC of 6amps then two panels in "parallel" would give you 19V VOC and 12amps ISC

but if you connected in "series" you would have a VOC 38V and ISC of 6amps and blow the D250SA

most 100w panels are around 18-24v VOC @ 6amp.

so the question is - - - - What panels have you got?


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page-8

1. Solar panel INSTALLATION EXAMPLES PREREQUISITES Solar panel capable of charging a 40–300Ah service battery. The D250SA uses MPPT (Maximum Power Point Tracker) to maximise the power from a solar panel.

TIP 1 Do not connect two solar panels in series. Max. input voltage 23V.

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https://www.ctek.com/storage/ma/b21...9E21271E091489ACEF47A/D250SA-manual-UK-EN.pdf
 
Hi all. I'm just planning out my electrics and will be purchasing the CTEK D250SA to power a 110Ah battery under the drivers captain seat. I'll also be mounting 2x100w flexible solar panels on the roof to utilise the CTEKS's direct solar input for off grid camping. Think I have all that element in hand but I see CTEK do a Smartpass device that can also back charge the starter battery and prevent a total discharge of the leisure.

I was considering this but not sure if there will be space to mount both the D250SA and Smartpass under the seat with the battery. I also have to ask, is it worth is as its not cheap.

Has anyone else produced a similar setup and installed all under a single captains chair?

Thanks


Have you looked at the stand alone Victron solar controller (VOC 75v/15A max):

https://www.travelvolts.net/product-page/victron-mppt-controller

SmartSolar MPPT 75/10, 75/15, 100/15 & 100/20 - Victron Energy

and the REDARC - BCDC1240D

DC-DC charger (which has a VOC max of 32V) ?

https://www.travelvolts.net/product-page/redarc-bcdc1240d

https://www.portablepowertech.com/l...55-5583bcdcpptdualenglishbrochure180413lr.pdf


.
 
The smartpass would certainly help to recharge a flat battery quickly by firing up the engine of you are off grids but with all that solar are you ever going to run it low enough to warrant the smartpass ??

Handy - yes
Required - ??
 
Just check that the DS250 doesn’t already charge the starter battery “as is”. I had the predecessor to it & once the leisure battery was charged it automatically topped up the starter.

Ps, I’ve also gone down the Victron 75/15 smartsolar route too. It’s a completely different animal.
 
As long as you don't use the radio or charge phones from the centre dash cigar socket then you are unlikely to run the starter battery down.
 
Thanks all.. I know if i run the 2 panels in Parallel only the amps double not the voltage so will be below the 23v threshold the D250SA can handle. I've looked at the 2 x 100w route as once above 100w, panels seem to get a fair bit more expensive. I've been looking at these but not bought any parts for any electrics as yet, just in planning.

Solar Panel, Flexible, 100W, 12V, 560640450004 | eBay

These would, in parallel give me a Voc of 21.6 V and Max amp of 11.12amps

The D250SA integral MPPT controller looks like it will be easily able to handle this so any need for a MPPT before the CTEK D250?

I think I will omit the Smartpass unit and save myself £200 isolating the starter battery from the leisure circuit. Seems a pricey option for small gain.
 
The DS250SA has a max through-put/charge rate of 20A from either Alternator or Solar (which is way enough to charge a Leisure battery/bank)

Charging of a service battery from a smart alternator (with variable charging voltage) -The D250SA can charge a service battery at up to 20A from the starter battery when a smart alternator is running.

Charging a service battery from a solar panel- The D250SA can charge and trickle charge a service battery from a solar panel at up to 20A. The D250SA uses MPPT (Maximum Power Point Tracker) to maximise the power from the solar pane


The SmartPass120 is just a way of giving you an additional 120A (so a total of 20A + 120A = 140A)

SMARTPASS 120 can be used on its own or in combination with D250SA. In combination, the D250SA and SMARTPASS 120 can charge at up to 140A.

So for just charging a Leisure battery 20A is enough and the SP120 would not be needed.

These would, in parallel give me a Voc of 21.6 V and Max amp of 11.12amps
- correct, so should be ok for the D250SA

No need for a separate Solar controller if you are happy with the D250SA doing the MPPT with those panels you listed . . . . . . . though moving forwards you might feel the need to add in some battery monitoring of some sort . . . .


Flexible Solar Panels & Solar Panels for Caravans & Motorhomes



like Cteck batt monitor, BM2 battery monitor, victron mppt, Victron BMV-712 . etc etc
 
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The DS250SA has a max through-put/charge rate of 20A from either Alternator or Solar (which is way enough to charge a Leisure battery/bank)

Charging of a service battery from a smart alternator (with variable charging voltage) -The D250SA can charge a service battery at up to 20A from the starter battery when a smart alternator is running.

Charging a service battery from a solar panel- The D250SA can charge and trickle charge a service battery from a solar panel at up to 20A. The D250SA uses MPPT (Maximum Power Point Tracker) to maximise the power from the solar pane


The SmartPass120 is just a way of giving you an additional 120A (so a total of 20A + 120A = 140A)

SMARTPASS 120 can be used on its own or in combination with D250SA. In combination, the D250SA and SMARTPASS 120 can charge at up to 140A.

So for just charging a Leisure battery 20A is enough and the SP120 would not be needed.

- correct, so should be ok for the D250SA

No need for a separate Solar controller if you are happy with the D250SA doing the MPPT with those panels you listed . . . . . . . though moving forwards you might feel the need to add in some battery monitoring of some sort . . . .

like Cteck batt monitor, BM2 battery monitor, victron mppt, Victron BMV-712 . etc etc

Yep, good call.
 
Just wondering how you got on with the install as I am in the planning stages here and have been looking at the CTek without the SmartPass as well
 
Hiya, not started yet as van is off having roof and springs done. Likely to start this in the winter I think
 
I've had my D250SA in for 2 years now with no problems. I never bothered with the Smartpass as I couldn't see a need for it, but I do have a Victron 100/20 next to the Ctek to handle my solar as the open circuit voltage of my panel is way over what the Ctek can handle. I do also have the tiny Votronic trickle charger under the seat too, like a few others on here. It trickle charges the vehicle battery when the leisure battery voltage is high enough. Just acts as a bit of insurance and stopped me needing to carry a jump starter after my Noco died.
 
Spot on, I think I will go for the D250SA to start with and then work out if i need Solar at a later point and a battery back jump lead set will do to start with.

Glad the set up is working well for you. I am planning on doing something like this ... in essence is it what you have gone for without the solar?
 
Spot on, I think I will go for the D250SA to start with and then work out if i need Solar at a later point and a battery back jump lead set will do to start with.

Glad the set up is working well for you. I am planning on doing something like this ... in essence is it what you have gone for without the solar?
More or less yes, though I don't have an isolation switch. You've put the Ctek SE in your diagram and I'd go for that if I was doing it now, gives the flexibility of being able to use a lithium battery
 
Yea i thought I would chuck in an isolation switch just so I can cut off everything "Camper" related for when I am just using it as a van or if it is left for a while not in use.

I also heard somewhere about putting in another couple of switches to allow you to jump the starter off the leisure if you ended up draining the starter battery by mistake... so might look into that a bit more but might be a bit overkill or simply not be a good idea.

These thought processes really do hurt my brain ... Ha!

Wire Idea - Jump Start (Jump).png

Wire Idea - Jump Start (Normal).png

Wire Idea - Jump Start.png
 
I recently fitted the CTEK D250SE (without Smartpass) and it seems to be doing exactly as it is intended. Seems to be a neat and quality bit of kit. I already had a separate solar regulator so I don't use the CTEK for that.

IMG_0966.JPG
 
Hi, I had the CTEK D250SE on its own, but was convinced to buy the smart pass 120s. Which is great as the van starts with a great boost from both batteries and has many benefits. Just a word of caution, if you intend to go for the smart pass 120s, you need 2AWG (at least) wire, I went for 40mm, and two 300 amp fuses from the starter and from the smart pass to the leisure battery. When you add in the wire and connectors and mega fuses it starts to add up believe me.
 
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