Tongsheng tsdz2 throttle stops with 48v horn

Joined
May 7, 2022
Messages
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Hello. I installed a 48v horn diecty to the battery with a momentary switch. The battery is 48v. What happens is that in pedal asist mode it will run as normal even when i hit the horn. But if I am just on the throttle and hit the horn at the same time it cuts power to the motor. If i stop the horn and keep the throttle down it does nothing. But if i stop horn release throttle and re-engage the throttle it works like normal. Is there a way to have the horn work without it cutting power when on throttle?
 
Hi Programinator,
And welcome to the forum! :)

Did you run both a dedicated ground and power wire to the horn? Or did you use some of the small wires in a typical harness for one or the other?



Regards,
T.C.
 
Doing some more testing today. My controller 850c is giving me an error 02H when i have throttle engaged and i blow the horn. Anyone know what that error code means. I have a rf choke on order and also plan to put a diode between the terminals on the horn. Hopefully that will help the problem. Any suggestions on this?
 
All the 850c manuals (AKA... DCP14) I looked at don't even have an 02H error listed... With the throttle error codes being 04H,05H, 06, and a 22, depending on OEM programming. :(

Have a link for the horn?

Are the wires for it tied closely to the cable harness for the throttle?
Is the horn mounted close to the throttle assembly?

From your electrical part fixes, I take it you saw this thread...
https://endless-sphere.com/forums/viewtopic.php?f=2&t=107982&p=1596214&hilit=diode+horn#p1596214

No experience there.
 
TommyCat said:
All the 850c manuals (AKA... DCP14) I looked at don't even have an 02H error listed... With the throttle error codes being 04H,05H, 06, and a 22, depending on OEM programming. :(

I seen the manuals too and didn't find that error code either :(

Have a link for the horn?

https://www.amazon.com/dp/B00FZUBUDG?ref=ppx_pop_mob_ap_share

Are the wires for it tied closely to the cable harness for the throttle?
Is the horn mounted close to the throttle assembly?

Horn is far from throttle but the throttle cable does run close to the horn cable


Yes i did and thats where i got the idea for choke and diode

Also the error 02h does come up while in pedal assist mode as well. Although not as much as when on the throttle. I did get it not to come up a few times while in throttle though.

Does this look like a noise issue?

Thanks
 
Yes, I would agree with you that this is a noise issue.
A vibrating, hi voltage coil wiring has to be very disruptive to electronic components.
Don't see the amp draw anywhere, what is it?

On the throttle link, the very first question was about losing ebike display when horn energized... :(

I'd probably try separating the wiring from the throttle cable. And if single strand wire. To TWIST them, say a turn for every inch.
If not try twisted pair, shielded, cable wire, grounded at one end only.
See if that makes a difference.
Then proceed with the added components, one at a time till the issue is resolved. :wink:
 
Tc,
Thanks for the help. I will try your suggestions and see what happens. Hope i can get it resolved because i like the safty aspect of having a loud horn. Will let you know how my progress goes.
 
FWIW, when I used a car horn (12v) on CrazyBike2, the electrical noise and load it created on startup was so bad that I could not power it from a DC-DC even with suppression (the DC-DC would either shutdown until power cycled, or just plain blow up), I had to use a separate battery just for that (whcih I also used for an old halogen car headlight).

A basic summary of how they work in general is quoted below since it was faster than typing it up; because it is a coil it will create a voltage spike bigger than what it was at when the current stops flowing (which happens many times a second); to the electronics attached to it it probably feels like a taser. :bolt: :bolt: :bolt: :shock: :lol:

The noise is not just on the power line, it's also on the ground, so if your DC-DC is not isolated, it will pass this noise back on it's ground to the battery and thus to everything else in the system. With a direct battery connection, it's "guaranteed" to do this.


Car horns work on the principle of a vibrating metal diaphragm. They are all electrically driven and consist of a solenoid (electromagnet) and a thin metal disc made of spring steel.

When energised, the solenoid exerts a magnetic force on the disc, causing it to flex concentrically. The flexing of the diaphragm moves apart the electrical contacts, thus de-energising the solenoid.

Once the disc springs back into its original shape, the electrical contacts close once again allowing current flow into the solenoid. The whole cycle is repeated for as long as the horn button is depressed.

The flexing and de-flexing of the steel diaphragm in car horns happens faster than the eye can detect. However, the resulting vibrations produce noise we can hear.
 
A basic summary of how they work in general is quoted below since it was faster than typing it up; because it is a coil it will create a voltage spike bigger than what it was at when the current stops flowing (which happens many times a second); to the electronics attached to it it probably feels like a taser. :bolt: :bolt: :bolt: :shock: :lol:

The noise is not just on the power line, it's also on the ground, so if your DC-DC is not isolated, it will pass this noise back on it's ground to the battery and thus to everything else in the system. With a direct battery connection, it's "guaranteed" to do this.

Thanks for the info. So are you saying its not a good idea to have the horn setup the way I have it?
 
If you power the horn directly from the same battery that runs the motor system, then if the horn is producing the same kind of electrical noise I got from mine, it can interfere with operation of other things on that same battery.

If you use a choke in series with either of the power wires to it as close as possible to the horn itself, it helps to "slow down" and absorb the voltage spikes from the switching happening inside the horn during use. A diode in series with the either of the power wires to it will help block reverse-voltage spikes. Between the two it may prevent the problems you're having.

Another possible problem is that the sudden current surge from the horn engaging is causing severe voltage sag on the battery, just for an instant, and the controller's power also dips and it doesn't respond well to that. Adding large enough value capacitors across the horn could help with this, on the battery side of the choke and diode.

Another option is to use a DC-DC to power the horn, and the DC-DC is isolated, meaning it's output wires do not connect in any way to it's input wires, then as long as the DC-DC is only powering the horn, the horn would not interfere with anything on the input side of the DC-DC (unless it radiates a lot of RF, which is possible if it arcs inside during operation).

You can measure a DC-DC for isolation by disconnecting the DC-DC from input power, then wait a few minutes, and then short the input leads together for a few seconds, then disconnect them. Then do the same for the output leads. This ensures there' no charge on internal capacitors, so you don't damage your multimeter. Then use a multimeter on 200ohms range (or autorange) and put it's red lead on the negative output wire from the DC-DC. Black lead on the negative input wire. You should read whatever the meter shows for no connection (OL, or 1., etc), if it's isolated. If you get a reading, that doesnt' change, it means the ground wires are probably connected inside, and it's not isolated.
 
amberwolf said:
If you use a choke in series with either of the power wires to it as close as possible to the horn itself, it helps to "slow down" and absorb the voltage spikes from the switching happening inside the horn during use. A diode in series with the either of the power wires to it will help block reverse-voltage spikes. Between the two it may prevent the problems you're having.

I'm going to try this first and see what happens

Another possible problem is that the sudden current surge from the horn engaging is causing severe voltage sag on the battery, just for an instant, and the controller's power also dips and it doesn't respond well to that. Adding large enough value capacitors across the horn could help with this, on the battery side of the choke and diode.

That seems to be the issue right there. Makes more sense to me. So if the chock and diode does not fix it would it draw less power hooking up a 48 to 12v dc-dc and then using a 12v horn instead of a 48v horn? Im not sure what the amp draw on the 48v horn that i have is. Does not say on the product page. But i see a lot of the 12v horns are 1.5 amp

Thanks
 
I don't know what the current draw on your horn is...but in general, to get the same work out of something (power, loudness in this case) then if you go lower in voltage the current must increase proportionally.

FWIW, the car horn I used (out of a 1985 Ford LTD) used quite a lot more than a couple of amps; I don't recall the numbers though. (might be in one of the old posts in the CrazyBike2 thread).

I suspect the 12v horn rating you're seeing is an average current, since with the type of horn described in the quote I posted there is no continuous current, just a switching current as many times a second as the frequency of the sound created, plus an initial turn on current spike thats probably even higher. Since these are usually used on a non-BMS'd battery, like a lead-acid, the load this creates doesn't usually affect things the way it can on ebikes/etc.
 
I had similar problem with my "light system", albeit opposite happened.When I pushed throttle or when the motor run, lights (NPN transistors which activate Mosfets to be precise) turned on because of the noise (on the battery, not between cables probably). The light system is connected to a DC-DC converter and run on 12V, and this still happened. I solved this by adding a ceramic capacitor to every transistors' base on my custom circuit.

Similarly, when I pressed horn (it's a ~1-1,5A motorcycle horn), lights sometimes turn on slightly probably because of a "big surge?". I believe I partly solved this with a ceramic capacitor, too.

Just wanted to add my experience, I'm not experienced enough to suggest a right fix.
 
solved this with a ceramic capacitor

This might be the way to go. I'm thinking more and more this is a power issue vs a noise issue. Horn still works good but i have to make sure motor is not running. So if i stop peddling or am not on the throttle its fine. no error. Maybe i will just leave it the way it is and just use it in case of emergency. like a car backing out of a driveway and does not see me. Idk we will see. I have the diode and noise suppressor. the Suppressor is for 12v so I don't even know if its good for my 48v battery system. Maybe somebody could advise me on that. plus im not sure where to connect the suppressor.

Thanks
 
Is the "suppressor" just a choke? (coil of wire on a "donut", wiht two connections)

If so, it works on "any" voltage; it just goes in series with one of the horn wires to the switch.

If the suppressor is something else, we'd need to know exactly what it is to say how to use it.

The diode can be used either of two ways:

it can be paralleled with the horn, with the arrow pointing toward positive (fat end of arrow on negative wire, line end on positive); if it doesn't have an arrow on it it will have a line on one end; that's the same as the pointy end of the arrow and goes to positive. This "shorts out" the negative-voltage spikes that come from a relay or solenoid coil being turned on and off, keeping them from getting back to other things in the system.

It can be seriesed with the horn; if it's in the positive wire then the arrow points from the battery/switch end toward the horn, so the line goes on the horn side of the connection.
 
Programinator said:
Is the "suppressor" just a choke? (coil of wire on a "donut", wiht two connections)

This is the one I purchased.

https://www.amazon.com/Pipemans-Ins...450794&sprefix=noise+suppressor,aps,86&sr=8-3

That site says it is probably a "pi filter", which is this:
https://electronicsreference.com/analog/pi_filter/
If it is, you can skip using the ground wire if you just use it as a choke. You can try the ground wire if it does nothing as just a choke, but if it has capacitors in it rated for only 16v (a possibility since it's meant for cars that use a "12v" (really 13-15v) electrical system, or maybe 30v as the next step up in cap voltages, those may fail at the 48v (42-54v) your system runs at.




Then on that one, the end with the gray line around it goes toward the horn's positive terminal, whether you use it as a flyback diode (parallel to the horn) or a series diode from the positive battery wire.
 
So i put the diode between the terminals. I also had one of those ferrite clip on chokes sitting around so i put that on the wires to the horn and looped it through the choke twice. Did some quick testing and have not gotten it to give me the 02h error yet. I'm not convinced that what I did solved the problem but we will see as time goes on...

Let me know if there are any dangers in the way i have it setup now. Thanks
 
Programinator said:
So i put the diode between the terminals. I also had one of those ferrite clip on chokes sitting around so i put that on the wires to the horn and looped it through the choke twice. Did some quick testing and have not gotten it to give me the 02h error yet. I'm not convinced that what I did solved the problem but we will see as time goes on...

Let me know if there are any dangers in the way i have it setup now. Thanks
Not that I can think of. :)

If it works--it works.
 
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