Advice on setting up Tongxin / Ping

andyh2

Esteemed Pedelecer
Jan 8, 2008
297
1
I've got the main parts together -Tongxin motor now built into wheel and Ping 10AH battery, but could do with some advice on the finer details of putting them together please.

The Ping charger has a 3 pin (only 2 are used though) male connector in metal. Does anyone know what specific female connector I need to attach to battery charge wires, or am I better off getting a new male and female connector and using that?

I've read somewhere that the Tongxin can put out a max of 10-15 Amps. The controller label says 'regulating current 12A'. For the wires which go from battery to controller and controller to motor what rating of wire should I use?

Should I put a fuse, or fuses, 'somewhere' in the system. If so where and what rating?

I have a waterproof connector for the motor but am unsure what connector to get for battery to controller suggestions please.

The Thumb throttle has 6 thin wires some of which connect up to the controller (some aren't used and I have all the wiring instructions for motor, controller and battery for what goes where). Recommendations for what type of wire to use for extending these wires appreciated too.

And lastly where to get these bits and pieces from.

Thanks
 

RobinC

Pedelecer
Jan 6, 2009
59
0
Bristol
I have a similar project under construction at the moment so am facing similar issues.

My Ping charger came with a socket supplied. Have you checked it isn't somewhere in the box?
This round 3 pin mains connector used to be commonly available but it is years since I bought one.

Are you using a 24V or 36V Tongxin?

Which connector are you using for the motor? I am thinking of using Canon Sureseal connectors which are waterproof & available in 3 pin but I officially I should use some specialised & expensive tooling for crimping etc. If I can't get by with basic tools I will have to think again.

I have seen speaker connectors used on some bikes. There are some connectors rated for tens of amps, but I guess not usually waterproof.

For more obscure bits I would try Farnell or Radio Spares first.

Robin
 

flecc

Member
Oct 25, 2006
53,560
30,849
Put a fuse directly in the battery positive line Wayne, a 20 Amp is common.

The charger should have it's own fuse.
.
 

frank9755

Esteemed Pedelecer
May 19, 2007
1,228
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London
There's a post by Ian in a thread started by Footy just over a year ago which contains a circuit diagram showing where the fuse should go.

I'm a little less keen on Tongxins than I was having had another controller (my fourth, including one from another vendor) blow half way round a week tour in the Netherlands. Fortunately I had considered it a possibility so brought my spare controller and was able to do a road-side swapout, and the bike is running again. Disappointing though, as I thought Tongxin controllers had been sorted out, but I guess not. The controller which blew had only done about 120 miles - (a similar distance to controllers 2 and 3 - I'm hoping 5 does a bit better as I don't have another spare with me!)
 

andyh2

Esteemed Pedelecer
Jan 8, 2008
297
1
Thanks Flecc and Frank. Disappointing to here about the controllers. I was hoping that with the reliability of the Cytronex bikes that that was a thing of the past.
 

RobinC

Pedelecer
Jan 6, 2009
59
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Bristol
Are you using the original Tongxin connectors Frank? Some have blamed connector problems for controller failure.
I think Cytronex uses stock Tongxin controllers & motors but use high quality connectors, so if they are proving to be reliable the anecdotal evidence supports this theory.

Robin
 
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wurly

Esteemed Pedelecer
Aug 2, 2008
501
9
Yeovil, Somerset
Frank, i have around 400miles on my tongxin controller now.
I am bit alarmed as to how many you have had go wrong.
I was going to buy another kit, but you are giving me second thoughts, have i been lucky so far?
What happens when they 'blow', do you get any idea they giving problems first or do they just stop working??

I don't have high quality connectors as my installation is still a bit of a lash up. I am using 2.5 spades. I can't see how this would affect it anyway. You are going to get an inrush of current no matter which connectors you use.

Mel
 

RobinC

Pedelecer
Jan 6, 2009
59
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Bristol
The Tongxin 3 wire controller senses the voltages on the motor wires to determine the current position to control the timing. Perhaps a dodgy connection could confuse the controller and cause some sort of misfire.
 

RobinC

Pedelecer
Jan 6, 2009
59
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Bristol
The Thumb throttle has 6 thin wires some of which connect up to the controller (some aren't used and I have all the wiring instructions for motor, controller and battery for what goes where). Recommendations for what type of wire to use for extending these wires appreciated too.

Thanks
I am assuming that these wires only carry a few mA so I plan to use some thin 6 way multicore cable - e.g. Maplin part no XR26D.
I haven't decided about the connectors for this cable yet.

Robin
 

frank9755

Esteemed Pedelecer
May 19, 2007
1,228
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London
I don't actually use any connectors, other than for the wheel. I have an IEC (kettle) connection on the front forks, to enable quick front wheel removal. For all the others, I just join the wires and cover with heatshrink (or electrical tape if I have to do it by the roadside!)

I suspect mine aren't lasting because I'm asking too much of them and they are failing to limit current in high demand situations. I use a fast 260 rpm motor, which enables high speeds in flat country. The last one blew after we had been doing a long cruise at fairly high speeds. I've asked my wife (who is using it) to avoid full throttle since then and we've been ok. When I get home I'll put a 175 rpm wheel in (same as the cytronex) and hope that my controller lasts as well as the Cytronex ones do!

Yes, any thin cable, such as burglar alarm wire, should be ok. I'm on my handheld so can't look up specific ones!

Frank
 

wurly

Esteemed Pedelecer
Aug 2, 2008
501
9
Yeovil, Somerset
That's interesting Frank. When i strapped a meter onto the handlebars to monitor my setup i noticed the current could reach 16A on occasions, and probably quite a bit more than the rated 12A.
I just picked up a 260 rpm motor from JohnP this afternoon (need more speed).....looks like i'll have to be careful of loading the motor too much.
I was talking to John about current limiters for more range from a battery pack, but i can see the advantage of also preventing over loading the controller, after hearing your account.
Is anything out there that can limit the current other than the controller itself??? a cycle analyst is way out of my budget.
Mel
 

frank9755

Esteemed Pedelecer
May 19, 2007
1,228
2
London
Interesting - confirms what I had suspected; the controller is not limiting current.
A fuse might be one way to do it. I was using a 20A but might start using 15A ones, on the basis they might go before the controller.
However you have got me thinking about a cycleanalyst now. They are not cheap but then new controllers add up if you get through a lot of them!

Frank
 

RobinC

Pedelecer
Jan 6, 2009
59
0
Bristol
The Ping charger has a 3 pin (only 2 are used though) male connector in metal. Does anyone know what specific female connector I need to attach to battery charge wires, or am I better off getting a new male and female connector and using that?
I've just noticed that Maplin have a suitable connector. Comparing the one that came with the charger and one in the shop this morning they look identical.
Maplin part number FM51F.

Robin
 

Tiberius

Esteemed Pedelecer
Nov 9, 2007
919
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Somerset
There's an important difference between limiting battery current and limiting motor current.

Most controllers, if they limit, will limit the battery current not the motor current. You can then get situations where large motor currents can still flow. I wonder if this is part of the problem.

Nick

PS. Robin, the charger connectors seem to be universally a type known as XLR
 

RobinC

Pedelecer
Jan 6, 2009
59
0
Bristol
There's an important difference between limiting battery current and limiting motor current.

Most controllers, if they limit, will limit the battery current not the motor current. You can then get situations where large motor currents can still flow. I wonder if this is part of the problem.

Nick

PS. Robin, the charger connectors seem to be universally a type known as XLR
The connectors that came with my charger are similar to XLR but different enough that they are not compatible - I just tried - the 3 pins of an XLR were wrongly spaced to fit into the plug.

Robin

p.s.
If the battery current were say limited to 15A wouldn't the motor current be limited? The current limit circuit probably would have to react quickly to protect the controller.

There are intelligent/smart power switch mosfet devices in RS/Farnell which have built in current limit but alot of them are designed for automotive applications so
the internal voltage clamps are rather low for a 36V system.

I was wondering if a circuit which actively reduces the throttle control voltage when too much current is being pulled from the battery would work as a cheap & simple
protection scheme. The Cycle Analyst power monitors have this function but it should be able to reproduce this feature with a fairly simple circuit.
 
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Tiberius

Esteemed Pedelecer
Nov 9, 2007
919
1
Somerset
The connectors that came with my charger are similar to XLR but different enough that they are not compatible - I just tried - the 3 pins of an XLR were wrongly spaced to fit into the plug.

Robin

p.s.
If the battery current were say limited to 15A wouldn't the motor current be limited? The current limit circuit probably would have to react quickly to protect the controller.

There are intelligent/smart power switch mosfet devices in RS/Farnell which have built in current limit but alot of them are designed for automotive applications so
the internal voltage clamps are rather low for a 36V system.

I was wondering if a circuit which actively reduces the throttle control voltage when too much current is being pulled from the battery would work as a cheap & simple
protection scheme. The Cycle Analyst power monitors have this function but it should be able to reproduce this feature with a fairly simple circuit.
Pity about the connectors; I'm not familiar enough with that type to know the answer there, sorry.

But with controllers, the motor current can be a multiple of the battery current because the controller/motor combination acts as a step down converter. What this means is that if you set a battery current limit, you may still exceed the motor limit in certain circumstances.

Nick