Zig CF8 poor output

[CJH]

The only problem is is that it doesn't suit my application- to directly power the leisure system. I'll have to rethink my plan!

My apologies if I've missed an earlier explanation, but why are you aiming to do it that way? If your leisure system is powered from your leisure battery, and your leisure battery is connected to the charger, isn't that the same, to all intents and purposes, as powering your leisure system from the charger? As stated^^^^, it'll act as a big capacitor.

Are you perhaps planning to power the leisure system without a leisure battery in the circuit? If so, a charger with a 'supply' mode might be what you want. I have a CF8 and I replaced the transformer with a CTEK MSX10 which has this 'supply' mode. In fact, I just rigged the CF8 so that the mains switch operates the MSX10 rather than the built-in transformer (just to keep the 'look and feel'), and so I do now have the option to run the leisure system directly from the mains, even without a leisure battery. I haven't ever needed that feature though.

[marlinowner]

Maybe something like this?

http://r.ebay.com/uIiD0n" onclick="window.open(this.href);return false;

[Bubble Meister]

My plan was to use a Ring Smart Charger to maintain and condition the battery. It defaults to 2amps when powered up and therefore wouldn't put our as much as the system would consume when in use - lighting, stereo etc. My plan was to have the system powered by the battery but, when a 240acv supply was available, the system would be powered by the zig unit (assume 15 amps max as that's the rating of the over current protection device). Simultaneously, the Smart Charger would kick in and condition the battery. This would all be achieved via a relay. Without mains power the battery would power the 12v system. With 240acv available, the relay would energise, connecting the 12v system to the zig instead of the battery. This would have worked but, as we know, the zig unit needs to be smoothed (using the battery). I don't think the Smart Charger would work well if the system is drawing a load off of the battery.
That eBay link seems like a similar replacement to the Zig and is reasonably priced.

[Bubble Meister]

Maybe I need to flip this on its head and ask: how can I use 240acv to power my 12v leisure system but also have the option to condition my leisure battery?

[ghost123uk]

My plan was to use a Ring Smart Charger to maintain and condition the battery. It defaults to 2amps when powered up

OK, I finally see where you are coming from. I got a 12 Amp Ring charger, about £32 from Motorworld and if the battery is any way depleted, it comes on at 12 Amps for a while, until the battery starts to charge, then it drops. Wonder why yours doesn't do this? Faulty?

On my van, my smart charger, is actually connected to a mains inverter that in turn is connected to what was the split charge relay, so now when my relay operates, it turns on the inverter, which in turn switches on the smart charger. I am VERY pleased with the way it looks after my leisure battery

[Bubble Meister]

This is the charger I have. It goes upto 8amps in increments of 2amps. On initial power up it default it's 2amps.

http://www.ringautomotive.co.uk/uk/prod ... us-/RSC508" onclick="window.open(this.href);return false;

But it's a charger / conditioner and not meant to drive the leisure system hence I was going install the zig too.

[Bubble Meister]

I wonder if the SCR and zener are something to do with protecting the 12v system if the 240 was wired the wrong way round. In the UK there is a convention for wiring Cee form plugs - in France they don't seem to have a convention - sometimes the live pin was live and sometimes it was the neutral!
Maybe it protects against reverse current?

[Bubble Meister]

Wow! That CTEK MSX10 seems to be the daddy! A Zig and a Ring Charger all in one! Yes it's over twice the price of the Ring but simple and compact and seems to do the job.
Two questions:
When I reconnect mains power would it automatically fire up in supply mode?
Isn't 15v a little high for maintaining a battery?

[ghost123uk]

This is the charger I have. It goes upto 8amps in increments of 2amps. On initial power up it default it's 2amps.

http://www.ringautomotive.co.uk/uk/prod ... us-/RSC508" onclick="window.open(this.href);return false;

That is the same design / series as mine and mine starts at full charging power, but only if the battery needs it. If the battery is already pretty well charged, mine defaults down to a lower setting. Could this be what is going on with yours? If your battery is pretty well charged, it will only supply a much lower current.

But it's a charger / conditioner and not meant to drive the leisure system hence I was going install the zig too.

As I mentioned earlier, if you dispense with the Zig charger and plumb that ^^^ in, it will all work just fine, with the the advantage over the Zig that it is a "smart" charger, as opposed to the simple Zig item. Your leisure equipment will all work as it should and when on grid, that charger will keep the leisure systems running and charge up the battery. No problems.

~~~~~~~~~~~~~~~~~~

Re the SCR, the suggestion it is there for summat to do with "wrong way round" mains input can't be it because it's on the secondary winding of the transformer.

[CJH]

When I reconnect mains power would it automatically fire up in supply mode?

I've never tested that, but I can say that when it's set to a particular charging program it remembers that between power cycles. So I've set mine to the 'normal' program and whenever I plug in to the mains the charger comes on in that mode without me having to touch it. In fact I've just seen this in the manual, in a section that refers to all four modes (normal, AGM, recond and supply), so it looks as though it will come back in supply mode if that's how it was left.

Settings are made by pressing the MODE-button. After about two seconds the charger
activates the selected program. The selected program will be restarted next time the
charger is connected.

Isn't 15v a little high for maintaining a battery?

In 'normal' mode it won't go above 14.4VDC unless it detects a sulphated battery, in which case it will run a desulphation program that pulses at 15.8VDC. It's perfectly safe to leave connected all the time, since once it detects that the battery is charged it drops to a maintenance charge of 13.6VDC.

It also has a temperature sensor - if you connect that to the battery being charged it will make sure the charging voltage doesn't go above the gassing voltage for the current temperature. In high temperatures this may be below 14.4VDC

Note that the slightly cheaper MSX7 also has this supply mode. But make sure they'll do what you want - I still can't say I understand what you're trying to achieve, but when they're in supply mode they won't be charging your battery optimally - they'll just sit at the 13.6VDC 'float' level regardless of the condition of your battery. Any smart charger should be safe to leave in charging mode, so that you get optimal charging at the same time as providing power for the leisure circuit.

[Bubble Meister]

Maybe I've completely over complicated everything? I thought that, with the Smart Charger connected to the battery, the load drawn by the leisure system may overload the Smart Charger and either blow it's fuse / protection devices or shorten it's life.

I've never seen the Ring Charger go above 2amps (unless manually selected).
I suppose a simple bench test could prove that the charger will work whilst the leisure system is in use.

It would save some pennies - I wish I had purchased the CTEK in the first place. (The Zig was only £5 from a scrap yard).
If I can find a small battery, I may use the zig as a 12v bench power supply.

[CJH]

Maybe I've completely over complicated everything? I thought that, with the Smart Charger connected to the battery, the load drawn by the leisure system may overload the Smart Charger and either blow it's fuse / protection devices or shorten it's life.

The charger will only provide what it can. In simplistic terms, if you're trying to draw 15A for your leisure system, and your charger can supply 10A, then you'll be drawing the 5A difference from the battery. Without the battery in the circuit, your leisure system would not receive all the current it needs, but it shouldn't damage the charger. For example, in the basic case of a 10A charger connected to a depleted battery, the battery would be capable of drawing more than 10A to recharge, but the charger is limited to 10A and doesn't get damaged by the battery being capable of drawing more.

Most chargers won't provide any output if they don't detect a battery. That's where the 'supply' mode of the CTEK chargers comes in, but it is only useful in the case that you don't have a leisure battery in the circuit. If you do, then just go with a smart charger that
a) matches it's output to the state of the battery,
b) comes back on in the mode you left it in (this is just for convenience), and
c) provides enough current to cope with your leisure system's demands. This doesn't mean it needs to cope with the peak demands (since the battery could do the 'topping up'), but on average the charger needs to put in as much as the leisure system takes out. Even that isn't strictly true, and depends how long you're going to be parked up, since your split charge system will top up the leisure battery while you're driving.

[ghost123uk]

+1 on that ^^^

[Bubble Meister]

I'm sure that I read somewhere that drawing a current from a battery whilst it's charging is not good. My understanding is that the 'Smart' charger detects that a load is being drawn and consequently shuts down.

Not bad, 5 pages of learning and plenty of direction with using my smart charger. I'm fully conversant with pulsing dc power supplies!

I see what you mean Ghost, polarity protection makes no sense on the secondary winding! Baffled! My understanding is that, when the earth is 5v higher than the rectifier positive terminal, the Zener will reverse, opening the SCR and allowing current to flow. But what circumstances would have the chassis at a higher potential than the rectifier? And why would you want current flow in that circumstance?

[CJH]

I'm sure that I read somewhere that drawing a current from a battery whilst it's charging is not good. My understanding is that the 'Smart' charger detects that a load is being drawn and consequently shuts down.

I can't see why that would be the case*. A depleted battery looks like a load anyway, so I think the only way the charger would know the difference is if the additional load is high enough to pull the battery voltage down. A smart charger bases it's output on the battery voltage I believe, so if the additional load pulls the voltage down the charger would think the battery is more depleted and would adjust it's output accordingly. So yes, it might get confused about the state of the battery, but in practice it's not a problem. It's certainly better than a 'dumb' charger in this respect - which is what a ZIG is, and what a smart charger in 'supply' mode becomes.

* E D I T: In my experience, this doesn't happen with my CTEK charger. When I'm on mains hook-up (usually only when parked on my drive in the winter) I can run things from my leisure battery without the charger shutting down or getting hopelessly confused or damaged.