5 1/2 hours at 1.87 amps (constant) looks like 10.3 amp hours.
How does that reconcile with the '5.329 amp hours added'
TSD2 range ?!
- Thread starter Simon Knight
- Start date
How does that reconcile with the '5.329 amp hours added'
In low assist on a gravel style bike with touring gear and trailer and all up weight 130 to 150kg, I average 10Wh per mile in fairly gentle terrain, and I am almost all ths time below the cutoff speed.
So if it is just you and the trike with a fair amount of time above the cutoff in gentle terrain and no big head winds, 4Wh is a bit low but not impossible. It may be that as a newish e rider you are trying harder than you need to!
So if it is just you and the trike with a fair amount of time above the cutoff in gentle terrain and no big head winds, 4Wh is a bit low but not impossible. It may be that as a newish e rider you are trying harder than you need to!
I set up a test rig this afternoon.
Here are the guide to the VLCD5's battery indicator, the TSDZ2 has factory firmware.
It follows from this table that Tongsheng programmed 43V-48V as the voltage range instead of 44V-54V.
You should charge the battery when the first bar is gone.
I won't blame you if you want to reflash your TSDZ2 with OSF firmware to rectify this issue.
PS: one annoying thing with the stock firmware: when you switch on the LCD, it shows all 6 bars first. You have to wait a few seconds (about 3-4 seconds) for the code to come round and update the bars.
Here are the guide to the VLCD5's battery indicator, the TSDZ2 has factory firmware.
| Voltage | Bars | State of charge |
| Above 48V | 6 | 50%-100% |
| 47V-48V | 5 | 40%-50% |
| 46V-47V | 4 | 30%-40% |
| 45V-46V | 3 | 20%-30% |
| 44V-45V | 2 | 10%-20% |
| 43V-44V | 1 | under 10% |
| Under 43V | 0 | 0% |
It follows from this table that Tongsheng programmed 43V-48V as the voltage range instead of 44V-54V.
You should charge the battery when the first bar is gone.
I won't blame you if you want to reflash your TSDZ2 with OSF firmware to rectify this issue.
PS: one annoying thing with the stock firmware: when you switch on the LCD, it shows all 6 bars first. You have to wait a few seconds (about 3-4 seconds) for the code to come round and update the bars.
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Well, that explains a lot! Thanks for doing this test, and makes a bit more sense why the 1st bar lasts for soooo long.
It appears I can get 25 to 30 miles in hilly area out of 1st bar with a fair amount of assistance and not hanging about. My initial assessment of 50+ out of a full battery looks about right if riding a little more conservatively.
C
I know why when I was on 3 bars the motor was struggling on hills. Unfortunately, flashing will void the warranty so I'm not especially keen to go down that route.
It appears I can get 25 to 30 miles in hilly area out of 1st bar with a fair amount of assistance and not hanging about. My initial assessment of 50+ out of a full battery looks about right if riding a little more conservatively.
C
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With my OSF tsdz2 , I can adjust the bars to suit an approx. voltage range for my 44v battery pack.
6 bars full 96 -100% 4.16 -4.2v / 49.9v - 50.4v.
5 bars 80% 3.98v / 47.75v.
4 bars 65% 3.85% /46.2v.
3 bars 50% 3.70v / 44.4v.
2 bars 35% 3.55v/ 42.6v.
1 bar 15% 3.37v / 40.4v
0 bars empty 3.20v / 38.4v
I set 3.2v as my min lvc.
Today having towed my heavy trailer over 25 miles on a mucky old rail line turned over by horses in places. The battery bar was flitting between 1 or 2 bars , at home a voltage check showed 41.3v or 3.44v per cell group, a quick balance check on the extra external balance wire added did indeed agree and all were at 3.44v.
So the OSF settings are pretty good and work quite well.
My wh rate is in double figures somewhere above 12 wh but less then 14wh.
Battery pack is 12s2p of Molicell p42a, 44v/8.4ah for 369wh.
BMS is a same port 20a Daly.
6 bars full 96 -100% 4.16 -4.2v / 49.9v - 50.4v.
5 bars 80% 3.98v / 47.75v.
4 bars 65% 3.85% /46.2v.
3 bars 50% 3.70v / 44.4v.
2 bars 35% 3.55v/ 42.6v.
1 bar 15% 3.37v / 40.4v
0 bars empty 3.20v / 38.4v
I set 3.2v as my min lvc.
Today having towed my heavy trailer over 25 miles on a mucky old rail line turned over by horses in places. The battery bar was flitting between 1 or 2 bars , at home a voltage check showed 41.3v or 3.44v per cell group, a quick balance check on the extra external balance wire added did indeed agree and all were at 3.44v.
So the OSF settings are pretty good and work quite well.
My wh rate is in double figures somewhere above 12 wh but less then 14wh.
Battery pack is 12s2p of Molicell p42a, 44v/8.4ah for 369wh.
BMS is a same port 20a Daly.
*SJPT - no idea why the reported Ah is less than the constant current multiplied by the time. Possibly because its a cheap uncalibrated watt meter. I have confirmed what the units are suppose to display " The displayed value is the total charge in Amp-hours (x1000=mAh) delivered since the startup screen ended"
The amps value of 1.87amps is an average value calculated every 0.4 seconds. I checked the display from time to time and either 1.87 or 1.88 amps was always displayed.
I will look out a known resistive load and attempt to get a rough calibration as I agree the values do not appear to make much sense.
*Mathewslack I agree that 4Wh per mile is rather low. I need to gather more data and where possible confirm the watt meter is working o.k.
* Woosh Thanks for publishing this table which answers my original questions about the display. You say "You should charge the battery when the first bar is gone." Did you mean this as it means recharge once the battery voltage drops below 48 volts? My 15Ah battery has a four bar display built into the side, three green LEDs and one red. At 47.1 volts this displayed 2 bars of charge. I am inclined to keep using the battery until only the red LED is illuminated, note the off load voltage and then recharge.
I have just reread your post and suspect you meant when bar number one goes out i.e. all bars out and a battery voltage of below 43 volts
* Bogmonster666 "Unfortunately, flashing will void the warranty so I'm not especially keen to go down that route." I'm with you. I will only look at flashing if I have issues with a rough power cut off which has been reported elsewhere. However, so far it has always been a smooth transition.
* Nealh Extrapolating your numbers the equivalent deep discharge voltage on my 48v battery would be 44.5volts (give or take), which I suspect will be close to my batteries single red LED or 2 bars on the main display.
On reflection having the display working in this slightly unexpected is not terrible. Bar six switches off at half charge and then each subsequent bar indicates a drop of 1 volt all the way down to 43 volts. In effect the display has finer granularity in the lower voltage region where it is most useful.
S
The amps value of 1.87amps is an average value calculated every 0.4 seconds. I checked the display from time to time and either 1.87 or 1.88 amps was always displayed.
I will look out a known resistive load and attempt to get a rough calibration as I agree the values do not appear to make much sense.
*Mathewslack I agree that 4Wh per mile is rather low. I need to gather more data and where possible confirm the watt meter is working o.k.
* Woosh Thanks for publishing this table which answers my original questions about the display. You say "You should charge the battery when the first bar is gone." Did you mean this as it means recharge once the battery voltage drops below 48 volts? My 15Ah battery has a four bar display built into the side, three green LEDs and one red. At 47.1 volts this displayed 2 bars of charge. I am inclined to keep using the battery until only the red LED is illuminated, note the off load voltage and then recharge.
I have just reread your post and suspect you meant when bar number one goes out i.e. all bars out and a battery voltage of below 43 volts
* Bogmonster666 "Unfortunately, flashing will void the warranty so I'm not especially keen to go down that route." I'm with you. I will only look at flashing if I have issues with a rough power cut off which has been reported elsewhere. However, so far it has always been a smooth transition.
* Nealh Extrapolating your numbers the equivalent deep discharge voltage on my 48v battery would be 44.5volts (give or take), which I suspect will be close to my batteries single red LED or 2 bars on the main display.
On reflection having the display working in this slightly unexpected is not terrible. Bar six switches off at half charge and then each subsequent bar indicates a drop of 1 volt all the way down to 43 volts. In effect the display has finer granularity in the lower voltage region where it is most useful.
S
I run OSF on a vlcd6 display and at power initially only just one battery bar shows then after a few seconds the true state shows. I always treat this time period, rightly or wrongly, as the boot up period during which time I keep my feet clear of the pedals whilst the torque sensor circuits are calibrated.
Might this behaviuor be what is happening with the OEM firmware?
Just an update. Going purely on the display bars (the 1st of which I think we have established goes out at 48v, here are my findings:
Yesterday I did a moderately hilly 36 miles. Some distance from the end the 1st bar momentarily flickered out, only to return for the remainder of the trip - including some hills. Recharged when I got home.
This morning I did 37 miles, probably with less hills, but still hilly. Today I was really finding it hard going, I think I am overdoing it as not cycling fit - my legs felt like concrete. Anyway, being very lazy on the last couple of hundred feet, the 1st bar flickered as I was practically turning into my drive.
I actually think my 10ah battery maybe not quite 10ah given the 50g cells used but close enough so let's ignore that. Looks like the voltage goes off a cliff shortly after 4000mah at around 3.3v which I suspect the lvc is?
Looking at an average discharge rate of 2a (per cell string), 54v to 48v delivers ~4000mAh(2000mAh per cell). Then the remainder of the battery delivers another ~4000mAh until 3.3v.
This was all based off cell discharge graphs I found on the interweb.
Realistically 5000mAh isn't achievable with the cells and getting to 4800mAh you are down to 2.4v per cell.
So roughly speaking the 1st bar gives 4Ah and the remaining gives 4Ah with a very linear discharge resulting in a usable 8Ah.
The 1st bar (goes out at 48v) gives ~200wh so at 37 miles that's 5.5 wh a mile.
The remainder of the battery should give ~180wh (due to lower voltage) so I might expect no more than 32 miles out of that.I will need to test the theory (have not felt confident enough to embark on a long ride with a half depleted battery yet) but I think 60+ miles is achievable for me in my surroundings, possibly approaching 70 miles, but no more. I expect that to be somewhat less in the colder months, although it was cold yesterday evening with a heavy frost. Playing it safe, I think 50 miles range is the maximum I would consider in these parts. That's quite good imo, but I guess I need to test the theory out in the real world as I made a lot of assumptions and there are a lot of variables.
Realistically I am unlikely to want to go much further than 50miles in a trip - and today I was definitely regretting the last detour and wishing I'd headed towards home sooner. The 10ah bag battery is a good size for my needs.
Early on I had gotten 50+ miles and down to 3 bars so the achievable range is proving remarkably consistent.
Yesterday I did a moderately hilly 36 miles. Some distance from the end the 1st bar momentarily flickered out, only to return for the remainder of the trip - including some hills. Recharged when I got home.
This morning I did 37 miles, probably with less hills, but still hilly. Today I was really finding it hard going, I think I am overdoing it as not cycling fit - my legs felt like concrete. Anyway, being very lazy on the last couple of hundred feet, the 1st bar flickered as I was practically turning into my drive.
I actually think my 10ah battery maybe not quite 10ah given the 50g cells used but close enough so let's ignore that. Looks like the voltage goes off a cliff shortly after 4000mah at around 3.3v which I suspect the lvc is?
Looking at an average discharge rate of 2a (per cell string), 54v to 48v delivers ~4000mAh(2000mAh per cell). Then the remainder of the battery delivers another ~4000mAh until 3.3v.
This was all based off cell discharge graphs I found on the interweb.
Realistically 5000mAh isn't achievable with the cells and getting to 4800mAh you are down to 2.4v per cell.
So roughly speaking the 1st bar gives 4Ah and the remaining gives 4Ah with a very linear discharge resulting in a usable 8Ah.
The 1st bar (goes out at 48v) gives ~200wh so at 37 miles that's 5.5 wh a mile.
The remainder of the battery should give ~180wh (due to lower voltage) so I might expect no more than 32 miles out of that.I will need to test the theory (have not felt confident enough to embark on a long ride with a half depleted battery yet) but I think 60+ miles is achievable for me in my surroundings, possibly approaching 70 miles, but no more. I expect that to be somewhat less in the colder months, although it was cold yesterday evening with a heavy frost. Playing it safe, I think 50 miles range is the maximum I would consider in these parts. That's quite good imo, but I guess I need to test the theory out in the real world as I made a lot of assumptions and there are a lot of variables.
Realistically I am unlikely to want to go much further than 50miles in a trip - and today I was definitely regretting the last detour and wishing I'd headed towards home sooner. The 10ah bag battery is a good size for my needs.
Early on I had gotten 50+ miles and down to 3 bars so the achievable range is proving remarkably consistent.
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