can I use a Y harness as a charging jack?

[FJ and G]

Thanks again!

[TonyWalsham]

David.

You cannot do it as the charger would be connected to the ESC at the same time as you are charging the battery.

Use a DPDT switch to isolate the ESC from the battery when charging.  Battery wires to the middle terminals, the ESC on one side and the charger on the other side of the switch.

You can also use a SPDT and switch either the positive wires or the negative wires.

[FJ and G]

I'm using only one battery. The Y harness connects the battery with the ESC. The extra end would serve as a jack for the charging unit. I hope I made it more clear this time. Sorry for confusion.

[TonyWalsham]

Hi Massey.

Thank you for the clarifications.

Battery R/C for trains is a whole lot different from R/C cars, boats and planes.  Please remember most LS train operators have never used batteries before and it is most important that the Do's and especially the Don'ts are spelt out clearly. Otherwise they might think what is OK for some cells is OK for all cells, when it is not.

It is possible to recharge NiCd cells when partially discharged, but only with a conditioning charger or at the regular 10% rate or less.  Otherwise the memory effect may manifest itself.  It is best to always trickle charge NiCd's anyway.  The batteries will last longer in terms of the number of re-charges possible.

[SMassey]

Massey,

In general I agree with most of your recommendations.  Especially the part about not charging mismatched cells. However, I don't know what your background is, but I should point out a couple of errors in your recommendations.

My battery knowlege comes from 20 years of R/C car racing and about 10 years of R/C boating.  I have delt with mainly NiCd and NiMH sub C batts for my cars and 6 or 12V sealed gels for my boats.

1.  Whilst you may be able to charge Lead acid chemistry in parallel, you should NEVER charge either NiCd or NiMh in parallel.  Unless the cells are computer matched one battery will take most of the charge and possibly get damaged in the process.  Don't believe me, go read the Sanyo service manual.

Yes I am aware of this I just didnt mention it.  I ment to but reading my post over again I see that I didnt.

2.  Whilst it is possible to charge some NiMh cells at 5+ plus, do NOT do it with AA cells.  You WILL severely curtail the life of the cells.

I should have mentioned that I was refering to the sub C variety designed for R/C car/boat applications.  AA type should not be charged over 1 amp they will leak and cause havoc or even explode. (I have seen this and it was not pretty the guy needed a new radio and recieved some burns on his hand)

3.  The dreaded memory effect of NiCd cells only comes about from rapid charging partially discharged batteries.  Always keep them charged as draining them to flat, ie below 1.1 volts per cell, may cause cell polarity reversal with dire consequences.

I race R/C cars and this was a big issue.  We did charge the batteries at high amps and only drain them partly durring the race.  I have NiCd batts for my cordless drill and they are doing fine still even tho there is some charge left in them when the pack hits the charger.

I cannot comment on Li-xx chemistry yet as I am still loath to use them in LS trains for the reasons given above.

 

 

I dont much like LiPo batts either, too dangerous for my tastes.  They are great in my cell and laptop but not in my cars, boats, or trains and since I dont fly I dont have to worry about my planes.

 

 

[TonyWalsham]

Massey,

In general I agree with most of your recommendations.  Especially the part about not charging mismatched cells. However, I don't know what your background is, but I should point out a couple of errors in your recommendations.

1.  Whilst you may be able to charge Lead acid chemistry in parallel, you should NEVER charge either NiCd or NiMh in parallel.  Unless the cells are computer matched one battery will take most of the charge and possibly get damaged in the process.  Don't believe me, go read the Sanyo service manual.

2.  Whilst it is possible to charge some NiMh cells at 5+ plus, do NOT do it with AA cells.  You WILL severely curtail the life of the cells.

3.  The dreaded memory effect of NiCd cells only comes about from rapid charging partially discharged batteries.  Always keep them charged as draining them to flat, ie below 1.1 volts per cell, may cause cell polarity reversal with dire consequences.

I cannot comment on Li-xx chemistry yet as I am still loath to use them in LS trains for the reasons given above.

 

[SMassey]

Your question is not that easy to answer but the basic answer is yes you can. 

Series Charging (Y harness wired +to- to give you 2x the volts) 

Here is where it becomes not so simple.  First off you MUST have both batteries in the same stage of discharge.  Both batteries MUST be of the same chemical type, and they both MUST have the same mAhrating.  This is not that easy due to the condition of each battery may be different even if they are the same age.  Fully drained is the best way to series charge a set of batteries.  Remember that most Gel batteries can be ruined by fully discharging.  You will need a charger capable of charging the total voltage of both batteries added together.  You can have a 12V and a 6V battery wired in series charging on the same charger at the same time if the charger is rated for 18V and the batteries have the same mAh rating.  In series the battery is viewed as one unit to the charger.  Most batteries are internally wired in series.

Parallel Charging (Y harness wired +to+ -to- for 2x the mAh, but the same V) 

Now for Parallel charing you also must have everything matched just as in series but you also have to match the Voltage.  You CANNOT wire a 6V and 12V battery in parallel. The 6V battery will start to charge at 12V and WILL blow up or catch fire.  Not good.  If you are charging batteries wired in parallel again make sure that they are in the same state of charge so you dont overcharge one of the batts and also you dont false peak the charger if you are using a peak detection type, this will leave one of the batteries with half or no charge.  When charging in parallel it will take about 2x longer to peak both batteries.   This is because you increase the mAh (capacity if you didnt know) and therefore it takes that much longer to charge.  Here is an example :  You have a charger that charges at 1amp.  Your one battery is 5Ah battery.  It will take 5 hours to charge this battery @ 1amp.  Now you have 2 5Ah batteries wired in parallel for a total of 10Ah it will take 10 hours to charge both.  You could get a charger that has a higher charging amperage but you still cant exceed the recommended max charging amps of your type of battery.

Here is a little storage and charging guide for different types of batteries.

Gel cell: Store fully charged.  Low internal resistance will not discharge durring storage. Charge @ about 1 amp.  Not likely to gain a discharge memory

Lead Acid: Store Fully charged.  Low internal resistance will not discharge much durring storage.  Charge below 5amps and in well ventalated area.  use ONLY distilled water if fluid levels are low.  Can be ruined if totally discharged

NiMH (Nickle Metal Hydride) Store fully to partially charged.  High internal resistance will discharge durring storage.   Can be charged @ 5+ amps if you use peak detection.  Batteries may need to cycled a few times after long periods of storage to get the full life back.  Will not gain a discharge memory

NiCd (Nickle cadnium)  Store fully discharged. Must drain fully before charging to keep from gaining a discharge memory.  Can be charged at 5+ amps if a peak detection charger is used.  Will gain a discharge memory, and will not charge properly if stored fully charged.

LiPo (lithium Polymer) Store charged.  Must use a discharge cut off to keep battery from discharging too much.  Charging amps vary somewhat in the cell configuration. MUST use a peak detection charger designed for Lipo batts.  These batts will catch fire if over charged.

 

hope this helps any of you that have any battery questions.

 

[FJ and G]

thanks

[calenelson]

I have to agree with Jack...the BIK makes it all a snap!

 

cale 

[Rastun]

David,

 From the schematic part you've shown that dpdt is wired to reverse polarity to the motor.

Here is a schematic of what I use.

It is taken from the simplified wiring diagram for a RCS basic 5 R/C throttle from the RCS company. http://www.rcs-rc.com 

The charging jack is a Radioshack 274-1583 or equivilent.

There should also be for battery and ESC protection a fuse in the positive wire from the battery before the charging jack connects in and a fuse in the red wire from the charging jack before it connects into the other wire.

 

Or you could just order a BIK-U-3 or BIK-U-6 from RCS or an RCS supplier here in the states and hook the wires up without having to do any soldering.

 

Jack 

[FJ and G]

jack, need advice (see below diagram); confused about what connects to what on the dpdt.

 

You have the battery now connected to the ESC. So the DPDT switch goes between those 2 components; then how is the battery charger wired into the dpdt switch?

 

 

 

 

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here's how the dpdt is wired (I'm visual person so a diagram would help):

 

THANKS!!!! 

 

[FJ and G]

thanks, Jack, the DPDT is a good idea; I like!

[Rastun]

It really depends on how the "Y" cable is wired. If it's wired to hook, say, two batteries into series then no it wouldn't work for charging because it would only connect to one side of the battery attached on the other  lead. If it's wired  so it takes a single  positive wire and a singe negative wire and splits them to become 2 of each wire then it could be used to charge if  the charging voltage won't damage what ever electronics you have mounted  on the other leg of the "Y".

Personally mine are wired so the battery hooks to a DPDT switch and so does the charging jack. With the switch in the "on" position battery power or power from the charging jack can continue on to the electronics. When the switch is in the "off" position power from the charging jack can get to the battery only.

I hope that's of some help.

Jack 

[FJ and G]

would this work? Is that how you guys do it or do you custom build your own device?

 

I have standard large 2 prong plastic hookup that you see a lot in Radio Shack r/c area.

 

thanks