Ctek D250s

Submitted: Friday, Oct 12, 2012 at 23:15
ThreadID: 98514 Views:7339 Replies:1 FollowUps:12
This Thread has been Archived
Hi everyone,
I have done some reading on the Ctek 250s on this site and decided to buy one. Now i can't find anything on wiring it. I would like to know what size auto reset circuit breaker i should use between the main battery and the positive terminal and the auxiliary battery and positive terminal and what size blade fuse for my 12v 240w solar panel?

I'm using 6B&S cable right through from car battery to camper battery

Any help for someone who has installed on them self or a auto lec that would be helpful.


cheers Sean
Back Expand Un-Read 0 Moderator

Reply By: Member - Phil G (SA) - Saturday, Oct 13, 2012 at 01:16

Saturday, Oct 13, 2012 at 01:16
The max current the d250s will draw will be around 25 amps.
The max current that a 6B&Scable can handle is around 100amps.

The circuit breaker/fuse/fusible link therefore needs to be at least 40 amps and less than 100amps, as its primary function is short-circuit protection of the cable running between the battery and Ctek.
No need for a fuse for the solar panel, as it is not directly connected to the battery.
Cheers
Phil
AnswerID: 496595

Follow Up By: Justahobby - Saturday, Oct 13, 2012 at 12:37

Saturday, Oct 13, 2012 at 12:37
Hi Phil,
Thank you for your reply. I'm using the 6B&S cable so I wont get any voltage drop. An auto reset of 50 amps will be fine then.

Cheers Sean
0
FollowupID: 772305

Follow Up By: Member - John and Val - Saturday, Oct 13, 2012 at 18:06

Saturday, Oct 13, 2012 at 18:06
Sean,

Sounds good, though I'd tend to use a fuse rather than an autoreset breaker. Why? If you have a problem the last thing you need is the breaker turning back on unexpectedly! I'd suggest using a 30A fuse, which gives another advantage - you can remove the fuse to ensure that things don't turn on while you are working on the system.

Another point - "I'm using the 6B&S cable so I wont get any voltage drop" ...... not really! There is always some voltage drop, though by using heavy cable as you are, it can be reduced. I'm all in favour of dc-dc chargers and use one myself. They do have one issue though that your heavy cabling should get around. Effectively, they draw extra current to provide an increased voltage, and without heavy cabling the voltage drop must be overcome by even higher current which leads to more voltage drop, calling for higher current still, resulting in more voltage drop, higher current..... you get the picture!!

I agree with Phil that you will probably not draw more than 25A. Something worth checking - can your alternator deal with the extra 25 amps? I've had the experience of 12A for the 3way fridge, plus 40A for a 30A dc-dc charger, plus a few more amps for lights and battery charging, all from a 55A alternator - not recommended, especially when the dc-dc charger draws extra amps as the voltage from the overloaded alternator goes down!

Cheers

John
J and V
"Not everything that can be counted counts, and not everything that counts can be counted."
- Albert Einstein

Lifetime Member
My Profile  My Blog  Send Message

0
FollowupID: 772316

Follow Up By: pepper2 - Saturday, Oct 13, 2012 at 18:50

Saturday, Oct 13, 2012 at 18:50
At the 4wd show today at eastern creek there were dc-dc chargers (by Motson ?) for $89
0
FollowupID: 772320

Follow Up By: Member - Phil G (SA) - Saturday, Oct 13, 2012 at 20:56

Saturday, Oct 13, 2012 at 20:56
Gday John and Sean,
Nothing is perfect, so I'd also be wary of the problems with fuses. When mounted close to the battery, the fuseholders can corrode very easily and develop high resistance. So if you are to use a fuse, then mount the fuse away from the battery (like the manufacturers do) with a well insulated cable feeding it. I've seen fuseholders corrode to an unusable state within 2 years. Also if you use a fuse, then use a maxi-fuse rather than the normal blade fuse. I think 30amps might be cutting it fine, which is why I suggest 40+.

Cheers
Phil
0
FollowupID: 772335

Follow Up By: Justahobby - Saturday, Oct 13, 2012 at 22:56

Saturday, Oct 13, 2012 at 22:56
Hi everyone,
I have decided to go with a 50amp manual reset circuit breaker. (unless someone can give me a downside?) I think this should be big enough and they are cheaper then a maxi fuse. It also means that if your out in the middle of no where and it trips it can be reset instead of buying or trying to find that spare fuse, and there is nothing worse then thinking you have fixed the short put a new fuse in and bang there goes your only spare.

Cheers Sean
0
FollowupID: 772343

Follow Up By: olcoolone - Sunday, Oct 14, 2012 at 18:32

Sunday, Oct 14, 2012 at 18:32
Why do so many harp on with "voltage drop", there are two types of voltage drop.... acceptable and unacceptable.

Voltage drop is usually caused by three issues..... faulty or bad workmanship or people trying to save a few cents...... in most cases it is a combination of two or three out of the three.

Acceptable is up to .3 -.5 of a volt in standard automotive applications unless we are talking 5v transducer outputs.

John :- re your comments about alternators...... alternators also have a duty cycle and most standard automotive ones hate running at maximum capacity for extended periods...... hence why some are starting to go water cooled.

0
FollowupID: 772377

Follow Up By: olcoolone - Sunday, Oct 14, 2012 at 18:35

Sunday, Oct 14, 2012 at 18:35
And Phil... you need two circuit protectors, one at the originating feed point and the other at terminating output point.
0
FollowupID: 772378

Follow Up By: Justahobby - Sunday, Oct 14, 2012 at 21:21

Sunday, Oct 14, 2012 at 21:21
Hi Olcoolone,
I don't understand what you mean by feed point and terminating output point. Can you please explain.

Cheers Sean
0
FollowupID: 772391

Follow Up By: Member - Phil G (SA) - Monday, Oct 15, 2012 at 00:29

Monday, Oct 15, 2012 at 00:29
Sean,what i think Olcoolone is saying (and it is aso what I do) is you need the same circuit protection at both ends - on the aux battery as well as the starting battery, because a short anywhere along your 6B&S cable can pull big currrent from either battery. As for the solar panel, it will be hooked directly into the CTek, so you don't need it fused. If your solar panel were to be directly connected to the battery, it is safest to use a fuse.
0
FollowupID: 772403

Follow Up By: Justahobby - Monday, Oct 15, 2012 at 07:33

Monday, Oct 15, 2012 at 07:33
Hi Phil,
So your saying to connect like this. positive to main bat 30cm away circuit breaker, then cable to Anderson plug at back of car then Anderson on camper then instead of going straight to ctek have another circuit breaker then 30cm of cable to the ctek.
Do i have to do this for the auxiliary battery it will be 30cm away from the ctek can i put a circuit breaker in the middle?

Cheers Sean
0
FollowupID: 772405

Follow Up By: Member - John and Val - Monday, Oct 15, 2012 at 07:46

Monday, Oct 15, 2012 at 07:46
Sean,

What Phil and Olcoolone are pointing to is the general rule that every significant power SOURCE should be fused (or circuitbreakered if that's a word!) Any connection to either the main battery or the auxilliary ('house') battery should be fused, since either can source serious current. You don't need a fuse on the input side of the ctek, (other than the one feeding it from the main battery) though there should be one close to the aux battery, which will amount to having one between the ctek output and the battery.

Cheers

John
J and V
"Not everything that can be counted counts, and not everything that counts can be counted."
- Albert Einstein

Lifetime Member
My Profile  My Blog  Send Message

0
FollowupID: 772406

Follow Up By: Jarse - Monday, Oct 15, 2012 at 08:06

Monday, Oct 15, 2012 at 08:06
Sean, i have a 50A auto reset CB next to the battery in the car. The Ctek has an inbuilt battery isolator, so I just ran 6 B&S all the way to the back to the anderson plug on the car. Have not had any problems with the CB.

The camper was wired with 6 B&S, and the builder terminated it with a 30A maxi-fuse. Not quite sure why it's only 30A, but I left it as-is and fed it straight to the Ctek when i installed it. I also have the Smartpass.

I didn't use a fuse between the solar and the Ctek.

The fitting instructions are a bit vague, but I just followed the pictures and the system seems to work okay.
0
FollowupID: 772408

Sponsored Links

Popular Products (13)