Large Scale Central

Battery not working ??

Electronics Power and Sound
#1

This is so frustrating. I have a small LGB engine that I am trying to battery power. I’m using a Piko 35040 RC pocket remote and receiver. I have a Airwire900 battery that is 14.8v 3.4Ah that works as it should but it is too big to fit in the cab so I bought a 4 cell battery off Ebay that will fit but it does not work. I did find out that the red wire is actually the ground and the 3 black wires are positives. The rating for this battery is 14.8v 3400mAh/50.32wh.

When attached the Airwire battery works well. When it is swapped out and the HQRP Li-ion battery is attached it will send volts through the on/off switch and into the board but nothing to the motor? The Piko board does not like this battery for some reason.

What am I missing here? Does it have something to do with the mAh ?

#2

Todd Haskins said:

This is so frustrating. I have a small LGB engine that I am trying to battery power. I’m using a Piko 35040 RC pocket remote and receiver. I have a Airwire900 battery that is 14.8v 3.4Ah that works as it should but it is too big to fit in the cab so I bought a 4 cell battery off Ebay that will fit but it does not work. I did find out that the red wire is actually the ground and the 3 black wires are positives. The rating for this battery is 14.8v 3400mAh/50.32wh.

When attached the Airwire battery works well. When it is swapped out and the HQRP Li-ion battery is attached it will send volts through the on/off switch and into the board but nothing to the motor? The Piko board does not like this battery for some reason.

What am I missing here? Does it have something to do with the mAh ?

Silly question maybe but have you charged the battery since you bought it, it may have only a holding charge that cannot supply the required current.

If you have a meter measure the voltage while under load ie connected to the board and see if it drops.

#3

GAP said:

Silly question maybe but have you charged the battery since you bought it, it may have only a holding charge that cannot supply the required current.

If you have a meter measure the voltage while under load ie connected to the board and see if it drops.

Yes I did charge it. The volts are getting to the board through the switch but then not getting out of the board to the motor. When I hook up the Airwire battery the motor works as it should using the remote control. There is no voltage drop with the battery that is not working. The motor does not work so there is no load on it?

#4

Educated guess based on the limited info you’ve provided Todd. The pigtail you describe; 1-red, 3-black sounds like the batteries balance charge pigtail (yet only four wires). Is there two pigtails? A picture might help. Use a voltmeter to validate pack voltage, cell voltage and polarity. Could be the battery is purpose built to be plugged into a device with battery/cell protection or similar ilk. Is is noted somewhere the battery has an onboard battery/equipment protection board?

Michael

#5

Michael Glavin said:

Educated guess based on the limited info you’ve provided Todd. The pigtail you describe; 1-red, 3-black sounds like the batteries balance charge pigtail (yet only four wires). Is there two pigtails? A picture might help. Use a voltmeter to validate pack voltage, cell voltage and polarity. Could be the battery is purpose built to be plugged into a device with battery/cell protection or similar ilk. Is is noted somewhere the battery has an onboard battery/equipment protection board?

Michael

Thanks for responding. Yes there is one red and 3 black. I cut the outer wrapping off the battery pack and found the 3 black are all soldered to the same terminal. I bought the battery on Ebay for $21 delivered. The ad read “HQRP Battery for RC Car Boat Robot Truck Tank Portable Electronic Devices MP3” and I thought why not trains too? I guess I was wrong. The pack came with one pig tail with 4 terminals. I cut this off and planned on soldering the regular type pig tail we use with our trains.

When connected directly to a motor the battery works fine but when connected to the Piko board it doesn’t.

I think I will keep my eyes open for a low cost 4 cell Airwire battery pack. When I last looked at a couple of sources they were sold out.

#6

Todd, looking at eBay I found your HQRP pack and the description says:

Li-ionCharging Controller Moduleinside

which I take to mean it has a battery protection board inside.

The pack came with one pig tail with 4 terminals.

The pictures on eBay don’t show 3 black wires so I am very curious about the ‘terminal’ you describe.

https://www.ebay.com/itm/274419864652

I often make my own packs and I find the protection boards are often the problem - they will sense a problem before you do.

But do be careful with your ‘re-wiring’. Make sure you are taking power from the P+/P- terminals of the protection board.

#7

That is the one I bought but the one I received has 3 black and one red wire that goes into a 4 prong connector. I cut it off with plans to solder the typical battery connection piece that my charger has.

I thought it would be a good battery pack for the small LGB porter and the price is great. What do you think Pete? It should work right?

I’m not going to rewire it because I do not want any issues like a fire or explosion. What would you suggest I do with it?

#8

Todd

How did you validate the red wire “NEGATIVE”? With a DVM? I’d ask the seller to send you another battery.

Michael

#9

What do you think Pete? It should work right?

It should work, right? Or it should work right/correctly? [Just kidding.]

If it was mine, and I had already started removing the outer wrapping, I would continue to un-wrap it until I could see the ends of all 4 cells. Then take a DVM (voltmeter) and check the voltages of all 4 cells - they should be about 3.7V +/-1V. Next, figure out where the 4 wires are connected - my initial thought was that they were from each battery pair.

This diagram shows how to wire a protection board, and there should be 5 wires. The batteries are wired in series (nose to tail, neg to pos,) and each end of the chain is wired to the B+/B- solder pads. The intermediate battery junctions are then wired to the B2,B3,B4 pads so the board can check them as they discharge or charge.

I have no idea why you have 4 wires, or why my eBay photo shows 2 wires. It is pretty easy to attach a photo here (“Manage Photos” at the bottom when you edit a post,) so we’d love to see what you have got, and where the 4 wires are connected inside the pack.

#10

please disregard.

#11

Todd,

Just curious. Could you take a voltage reading from the Red lead to each one of the black leads?

#12

This looks to me to be a typo:

they should be about 3.7V +/-1V.

I would think it is .1 volt, I can not believe a 3.7 battery can go to 4.7 volts!!

#13

Here is the top of the battery and the connector I cut off. It is odd that it has 3 negative wires that all go to the same spot on the board.

Don Sweet Emailed me and said that the PIKO boards are basic but they can also be finicky and basically that is why this cheap battery is not working with it.

#14

Dan Pierce said:

This looks to me to be a typo:

they should be about 3.7V +/-1V.

I would think it is .1 volt, I can not believe a 3.7 battery can go to 4.7 volts!!

Dan, I was a little casual in my statement, but the Li-Ion battery protection, like the one I pictured, will stop charging at 4.25V and stop discharging at 2.54V. Almost a 2V difference. You do have to be aware that a fully charged battery can by 4.25V, not 3.7V.

Here is the top of the battery and the connector I cut off. It is odd that it has 3 negative wires that all go to the same spot on the board.

Yes, very odd, but it seems to be wired as I’d expect. Can’t see why the Piko board is finicky - maybe Don has more insight!

It might be that the protection board is charging up to 4.4V, which is not unheard of. Maybe the Piko doesn’t like the higher voltage? Suggest you compare the voltage of the pack with your other ones and see if there is any minor difference.

I also have used diodes to drop the voltage on such a pack - I have a bunch of 10A diodes that drop about 0.3V in each one. 3 or 4 in series can take a volt or 2 off the total.

#15

I’ve done three battery conversions for fellow club members using the Piko 35040 setup and I haven’t had any troubles other than the board not firing on its motor output once as I accidentally had the polarity wrong. I’m assuming that you are running the battery power through the little TRACK <—> BATTERY power switch / diode module, correct ? If so make sure you have the polarity correct between of the output terminals from this board to the 35040. Make sure you wire the battery to the battery +/- and track feeds (if you are retaining your pickup / brush feeds in your loco) to track L and R rail input otherwise you are wasting voltage (and limiting current as well ) through the Schottky diodes on this board if you get it backwards.

Also, are you using the 35040’s sound trigger outputs or headlight connections ? If so make sure you haven’t accidentally gotten something crossed up are not loading down the 35040 in some way.

14.4 volts or even 18 is NOT too high for this board. Its rated at 22 volts max at 3.5 amps max continuous. It uses an 8 pin H bridge MOSFET chip to do the motor drive, using PWM to drive the fwd / reverse control inputs to this chip.

Dave

#16

David Jones said:

I’ve done three battery conversions for fellow club members using the Piko 35040 setup and I haven’t had any troubles other than the board not firing on its motor output once as I accidentally had the polarity wrong. I’m assuming that you are running the battery power through the little TRACK <—> BATTERY power switch / diode module, correct ? If so make sure you have the polarity correct between of the output terminals from this board to the 35040. Make sure you wire the battery to the battery +/- and track feeds (if you are retaining your pickup / brush feeds in your loco) to track L and R rail input otherwise you are wasting voltage (and limiting current as well ) through the Schottky diodes on this board if you get it backwards.

Also, are you using the 35040’s sound trigger outputs or headlight connections ? If so make sure you haven’t accidentally gotten something crossed up are not loading down the 35040 in some way.

14.4 volts or even 18 is NOT too high for this board. Its rated at 22 volts max at 3.5 amps max continuous. It uses an 8 pin H bridge MOSFET chip to do the motor drive, using PWM to drive the fwd / reverse control inputs to this chip.

Dave

Thanks for the input David. Of course wiring the Piko is a concern but it is correct because I have run this locomotive with another battery and it works great. I am using the headlight connection and that is it. There is something going on with the battery or the Piko not liking what the battery is feeding it. The one that works is a $50 Airwire 14.8v 3400mAh. The one that does not work is a $16 14.8v 3400mAh that is used in RC cars,boats and other electronics.

I’m starting to think this is a case of “you get what you pay for”.

#17

Todd

You mentioned polarity ID colors were backwards? Looks like RED is soldered to P+ and black to P- which is correct. Must have been a Monday at the battery assemblers place, definitely a 4 cell battery with a PCB and 3 cell balance charge plug.

Anywho this battery should work fine for your needs, unless its damaged.

Michael

#18

Batteries can do odd things. As an example; I have a Airwire eight cell 6800mah battery that will work fine with G3 decoders but will not work with the older decoders. I have several of this type battery. Only this one battery fails. Sounds the same as Todd’s problem.