dual battery charger options

[delwynv]

hey guys & gals

haven't found many topics on the wrnd producs

opinions of the WRND WDB1220B charger Vs Ctek 250s


and just throwing in a curve ball the national luna split charger (just for interest sake)

[Dungbeetle]

Whatever you do stay away from direct connection and solenoid systems such as NL

Only do DC-DC systems

Start by checking:

https://www.hcdpelectronics.co.za/

http://www.4x4direct.co.za/

http://www.bushpower.co.za/products.asp?pc=27

[Jack Russell]

An insightfull discussion here
http://www.4x4community.co.za/forum/...-DC-DC-systems

[Eggie]

Whatever you do stay away from direct connection and solenoid systems such as NL
Only do DC-DC systems

Mmmmmm...
You should really qualify why you say this.

Direct connection works very well for some, and for some others it does not.
It can be the ultimate in simplicity and low cost.

[Fluffy]

Mmmmmm...
You should really qualify why you say this.

Direct connection works very well for some, and for some others it does not.
It can be the ultimate in simplicity and low cost.

Exactly.

[DC Polokwane]

I have been using the WRND WDB1220B (DC to DC Charger 20Amp/Solar MPPT) with 2 x 105 dc batteries and 2 x 120w solar panels and I am very happy with it!

The Ctek is R6000-00 vs the WRND's R2000-00

The National Luna Battery Manager Kit (R2000-00) is good provided your vehicle has a decent alternator. No solar charging option included.

[pardus]

Anyone actually measured the current flow from this charger? I have a HCDP DCDC 30A charger that has never exceeded 14A on a different 50% DOD batteries. Would be interested to know if this one does actually charge at 20A during bulk charge.

[Dungbeetle]

Anyone actually measured the current flow from this charger? I have a HCDP DCDC 30A charger that has never exceeded 14A on a different 50% DOD batteries. Would be interested to know if this one does actually charge at 20A during bulk charge.

I had one of those older 30A HcdP DC-DC MPPC chargers- its a serious machine and I have seen 27A with it...from Car alternator to 4 very flat Varta LFD75 batteries

(It has been replaced by the new HcdP 20A - which is in fact a 30A system if you take the bypass action in count)

What is the exact model name of yours

and

That 14A - was it while Linked to Car or Solar, if Solar what total Panel Watts ?

[Eggie]

It is also important to monitor the voltage of the battery under charge.
Should the voltage reach 13,8V or more, the charger will probably start tapering off. Should that voltage kick off high, then the full charging current will not materialse, simply because it is designed that way.

Put a heavy load on the battery (a biggish compressor at 35A will do) and check the DC-DC's performance that way.

[pardus]

Model number DCDC30A (before the auto switch), into a good 105Ah deep cycle battery, 14A measured at 12.8V, 180W, charging from the car via 3.5m of 10mm² multistrand wire.

Maybe there's something wrong with mine.

[Eggie]

Model number DCDC30A (before the auto switch), into a good 105Ah deep cycle battery, 14A measured at 12.8V, 180W, charging from the car via 3.5m of 10mm² multistrand wire.

Maybe there's something wrong with mine.

When you describe it that way, something is wrong with the HCdP.
(Not sure what you mean with the 180W?)

[Dungbeetle]

Model number DCDC30A (before the auto switch), into a good 105Ah deep cycle battery, 14A measured at 12.8V, 180W, charging from the car via 3.5m of 10mm² multistrand wire.

Maybe there's something wrong with mine.

I assume the 180W you ref is 14A x 12.8V = 180W

There is a problem somewhere, but not necessarily with the DC-DC

Note that that 30A DC-DC will start dropping the charge current when it senses low supply voltage - see:

Warning
Our DCDC30A charger is a serious machine that can draw up to 50A from your vehicle's alternator. In order to protect your alternator we have included a feature that reduces the charging current progressively if the input voltage from the alternator drops and approaches 13V. It is therefore necessary to use wire sizes as specified to prevent charge current reduction as a result of voltage drops over supply wires.


Meaning:
If your battery voltage is 12.8V whilst being charged and the charger also senses more that 13V from the alternator, it will (like mine did) charge almost 30A.
If in the above case the supply voltage reaches 13V or drops below 13V the charger will start limiting current in order to try and keep the supply voltage above 13V
If the supply voltage keeps on dropping and reaches 12.5V, the charger switches off.

The charger (depending on version) also has a sensing/ignition connection on the terminal - it is best to wire that via a 1.5mm wire all the way to the main battery/alternator. In this way the charger will sense actual Alternator voltage and not the voltage at the input of the charger.

Now, if you sense at the charger and have some voltage drop over your supply cables that causes dropping below 13V, the charger will try to limit the current.

[Dungbeetle]

See this proper way to wire it

[Poen]

I use an HCDP 12 VDC to 14 VDC 12 amp charger fitted under the dashboard, charging two auxillary batteries which in turn powers a 12 volt compressor fridge each.
The 105 ah deep cycle battery under the bonnet as well as the caravan deep cycle battery is fed from this same auxillary battery terminal on the charger.
The fridge in the boot is powered from the "Load" terminal on the charger.
A headlight type relay cuts the feed to the caravan when ignition is switched off.
Although there are two batteries in the caravan only one is connected to the charger at any given time.
I found the fridges to be running happily whilst driving, and the batteries are always full by the time we reach our camping destination – starting out with fully charged batteries of course.
I have been running this set-up for a few years in my previous car, and installed the same components when changing cars fairly recently.