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Tmax 500 2008- charging voltage ?

16K views 65 replies 2 participants last post by  pellicle 
#1 ·
I have a tmax 500 2008, which is the correct charging voltage?

mine is 13.7v at 1300rpm and 13.9-14 at 3-4000 rpm
if starting the long beam drops to 13.2 and at 4000 13.5 maximum.. is normal?
 
#52 ·
also @Smiley32
you need to ensure that you do any voltage testing with the bike cold (meaning room temperature) All manuals are written with this as a pre-condition unless it is mentioned specifically to use a temperature. All gaps are measured at room temperature (and if precision is needed I understood its assumed to be 20C)

Copper (the wire used in the altnator) has a different resistance at different temperatures:
https://www.electronics-notes.com/artic ... icient.php

So when the altenator is sitting in hot oil (on the end of the crank as it is) then the amount of V that you'll get from it will fall.

Also battery voltage settles after charge and discharge. The capacity of the battery in Ah is usually given at a particular dischage rate which is related to its capacity (C). Usually discharge is measured at C so if you have a 10Ah battery it can be discharged at 10Amps for an hour and it will be depleted. Some cheapo batteries sneak in their Ah ratings by putting C/10 in their spec (meaning 1 amp for 10 hours) but will fail to give 10 amps for 1.

https://batteryuniversity.com/learn/art ... the_c_rate

A headlight bulb of 55W bulb will draw around 4.5 amps @ 12V, just as a reference.

Reading the battery spec it says that: discharge at 1C (8.5 A to 9.6V) = 3.8 Ah which is a damagingly low discharge voltage, you should not discharge it below 10.8 if you want it to live. Reading the specs it will only deliver 8 hours if you power something miserable like a 5W stop light.

I am concerned about the temperatures you are measuring at because you discuss the thermo fan coming on. This should not be happening (unless you have wired it to do so). Why is the thermo fan coming on?

Is your thermo fan on frequently when riding? If so you may have a cooling problem (such as the thermostat is not working and failing to open).
 
#53 ·
Hi, after 7 days with battery connected, first start 5 grade temperature

Very low crank, but start... I'm going 20km and then another 5 days stay off then I find the scooter with the discharged battery :(

No problem with the termostat, fan is on only when is very hot.



Ps: sory for the vertical film :lol:
 
#54 ·
Smiley32 said:
Very low crank, but start... I'm going 20km and then another 5 days stay off then I find the scooter with the discharged battery :(
this new description suggests something entirely different to what you have been discussing. If I am reading between the line properly on this post I assume the following
  • battery is charged[/*]
  • bike is then parked and not operated for 5 days[/*]
  • battery is then flat (discharged)[/*]

if this set of assumptions is correct then it suggests you have a power leak in your electrical circut somewhere.

If you place an amp meter in series with the battery (negative or positive) with the ignition turned off and the seat closed is there a drain on the battery? (there should not be)
 
#57 ·
Smiley32 said:
Yes is a leack of 0.017A

The initial problem is battery discharge when the scooter stay off, my doubts that it does not charge the battery properly...
0,017I do not think it's a big deal
I agree ... 17mA is not anything significant. Not over 5 days.

I find it hard to asisst with difficulties in problem description (which I believe are logical not linguistic) and the initial statement of the problem. Can you perhaps assist by making a time related list of (very simple english is all that's needed) bullet points.
 
#58 ·
Smiley32 said:
I forgot to mention that the RPM reached did not seem like 3000rpm to me ... but on the brief rev it did seem to go high enough.

However these videos provide far far less than useful detail because you don't explain anything about them (just slap it up there). You don't say
  • what is the purpose of the demonstration[/*]
  • which regulator was used[/*]
  • was the vehicle started from cold or hot[/*]

I mean its not like we haven't been discussing this for a while for you to understand what any diagnosis needs.
 
#59 ·
Hi, my immo emulator is the problem, the curent consumtion is 0.017 with immo

0.017A/h X 24h = 0.408A X 10 days = 4.08A drain

I make a software solution for immo off, now the current is wery little current drain 0.001A



Now, if i dont have current drain, if i drive 7-8 km i dont have problem with flat battery!

In conclusion the charge of 13.8v-14v is ok! I do not think Tmax since 2008- 2011 has a better chargin voltage! please the Tmax 2008+ owners to confirm...
 
#61 · (Edited by Moderator)
Smiley32 said:
In conclusion the charge of 13.8v-14v is ok! I do not think Tmax since 2008- 2011 has a better chargin voltage! please the Tmax 2008+ owners to confirm...
correct, it is actually the ideal

https://batteryuniversity.com/learn/art ... id_battery



and ... Table 2 compares the advantages and limitations of various peak voltage settings.

fig1.jpg
 

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#62 ·
This may be unrelated to the testing I did, but it may. So anyone considering my battery terminal removal (with the engine running) to test charging should have a quick read of this blog post

https://cjeastwd.blogspot.com/2019/03/b ... -wire.html

I remain uncertain why it would be the cause, however I discuss that in the post. But as coincidences go its too tight and I thought I'd repair it. Besides, as I do believe "no good turn goes unpunished" I expect this is my punishment from The Gods for helping...

and besides, someone may know an explanation for why it was the cause and post that answer on my blog (or here, or both).

Best Wishes
 
#65 ·
Hi, i change the normal rectifier with the MOSFET one...



I can say that I am very pleased, the voltage is more stable, when I start the consumer drops very little, the regulator's temperature is very good, the original is very hot, you can not touch it after 15 km
 
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