New Luna DPC14 Color Display...

[DrDave]

I received my DPC14 and recently installed it - very easy. I really like this dashboard.

Couple of questions though. The battery info section is probably one of the most important features of this display. Remaining capacity in mAh is probably one the most important means to determine how much juice is left in the pack, along with average current in mAh. The manual states this information is supported by battery communication.

How does one create that battery communication? Also, I have a 52V 13.8 Ah SharkPak. How do I set the user defined voltage on the UBE setting - or is it just internally referenced. The voltage display does show 52V at full charge, FWIW.



Thanks for the help.

David

[Sebz]

Good question, I hope there is a solution..... I do not want another display but want Wh and Ah!

[Sather]

I would settle for an accurate volt meter. My battery measures 57.4 by my Fluke meter, but the DPC14 display says its 55.8 volts. Unless this can be adjusted to be accurate, the display is not worth buying.

[Sebz]

Thinking about it, this fonction is like a battery monitor software on a laptop. On my mac I use coconut battery and it gives me all this info... The battery on a mac has some kind of communication with the BMS... I do not think our BMS's can communicate with the DPC14... Maybe it's a new kind of battery or BMS that Bafang is putting together? Who knows? I haven't received my batt pack yet so I cannot play with the display!

Maybe next time Luna chats with Bafang tech support, they can ask about this really nice fonction?

[Marc]

Can we get a answer on the UBE 52v battery setting?

[Eric Luna]

We have found no way to make the little graphical display graph of battery guage to be accurate.

The UBE is also unclear to us now it functions.

We know that the battery guage does not read much over 54 volts........ the full charge voltage reading of a perfectly balanced 52 volt batttery is 58.8.

This may help you to determine battery usage based on voltage:

State of Charge Chart for Panasonic NCR18650B (Luna 52v)


Single Cell / 14 Cell / Capacity

4.2 / 58.8 / 100%

4.1 / 57.4 / 94%

4.0 / 56 / 83%

3.9 / 54.6 / 72%

3.8 / 53.2 / 59%

3.7 / 51.8 / 50%

3.6 / 50.4 / 33%

3.5 / 49 / 15%

3.4 / 47.6 / 6%

3.3 / 46. / 2 0%

3.2 / 44.8 / 0%

Measured 1 hour after discharge, resting voltage

For battery life sake fo now let fall below 44v.

[Sebz]

That's great info Eric.... At least till I get a Batt man or a CA

[wheelwatcher]

Where are you getting these values, Eric? They seem a bit off from those here: http://www.ebikes.ca/tools/charge-simulator.html. Is one theoretical and another real world?

[Marc]

Thanks Eric.

[FlyByFun]

A little bit disappointing, as I understood this display to fully support 14s/52V batteries. I hoped for this display to not need a second display to get accurate readings from 52V batteries. Maybe a software-update in the future will fix this?

[WebEsquire]

Same issue here - battery percentage indicator always shows 100%. Also, the Battery Info screen has virtually no information - all fields are blank. I'm using the 52V 11.5 ah panasonic bottle battery. Has anyone gotten the Battery Info screen to work at least?

[Bicycle365]

Thanks for the chart Eric

I'm the kind of person that likes things orderly and the drops in voltage per cell of .1v produce a percentage difference of between 6 and 13 and its not linear. I know that batteries don't produce a linear power curve but It helps me "follow along" better if I have smaller increments.

SO....

Using 58v as the top end, since not all packs will get 58.8 everytime for their whole life, and using 45v as the bottom since Eric said not to go below 44v ( not sure what the LVC is on a Luna 52v pack) that gives me a little fudge factor built in for the low end. What I get is this.... I'll be using this until I figure out exactly what to expect for range and life since Im so new to all this.

[Sebz]

Thanks for the chart Eric

I'm the kind of person that likes things orderly and the drops in voltage per cell of .1v produce a percentage difference of between 6 and 13 and its not linear. I know that batteries don't produce a linear power curve but It helps me "follow along" better if I have smaller increments.

SO....

Using 58v as the top end, since not all packs will get 58.8 everytime for their whole life, and using 45v as the bottom since Eric said not to go below 44v ( not sure what the LVC is on a Luna 52v pack) that gives me a little fudge factor built in for the low end. What I get is this.... I'll be using this until I figure out exactly what to expect for range and life since Im so new to all this.

Great, I will print that out and keep it in my pocket while riding till I can remember key voltage references

[Sebz]

And so for the yesterday ride I used 34% of the total capacity for 20km running on the throttle and ghost pedaling 90% of the time, averaging at 27kmh (including stops and check ups). stop and go every 2 minutes in the city. Quite impressed on battery life so far.

[Louis]

There has NEVER in a annals of eBike displays, been an accurate OEM wattmeter or battery gauge. At least out of all the Bafang, ebikekit, Magic Pie and the China made. I ride till the motor flutters and never ride that far again. Haven't been stuck yet. I have EVERY gauge. So far my odometer has been the most accurate. I put one of my meters on a new ride and sort the mileage, sometimes. Either way I'd rather ride than read gauges. I'm old...

I'm sorry, I don't mean to marginalize, but I do. This isn't all that difficult or disappointing to me. If its so easy for an old guy with a stroked brain to sort, why is it so difficult for everyone else. VBG

[Sebz]

Are old are you Louis, you speak like my 75 year old dad....and he would never ride a BBSHD :)

[Louis]

To close for comfort, son. VBG

[Sebz]

I'm gonna call you "papi" then!

[Ade]

There has NEVER in a annals of eBike displays, been an accurate OEM wattmeter or battery gauge. At least out of all the Bafang, ebikekit, Magic Pie and the China made. I ride till the motor flutters and never ride that far again. Haven't been stuck yet. I have EVERY gauge. So far my odometer has been the most accurate. I put one of my meters on a new ride and sort the mileage, sometimes. Either way I'd rather ride than read gauges. I'm old...

I'm sorry, I don't mean to marginalize, but I do. This isn't all that difficult or disappointing to me. If its so easy for an old guy with a stroked brain to sort, why is it so difficult for everyone else. VBG

It's all about range anxiety. Because of mine, I fully charged my current battery every day which probably got it to its current, not particularly good state in 15 months. People sort of expect a close approximation of battery level if nothing else.

How accurate is this display with 48v batteries?

[Louis]

It's a close approximation.