Very short low battery warning on NX5

[Adam Welz]

Hi All

another thing that worries me: The other day I ran a battery flat in the camera for the first time. The warning time given by the cam was, however, extremely short.

More on my blog here:

Very short low battery warning on Sony HXR-NX5U with NP-F970 battery Adam Welz's NXCAM Blog

Daniel, perhaps you have had a chance to run a battery flat? How long was your warning?

Cheers

Adam

[Daniel Paquin]

Hello Adam,

I do not know if I am the Daniel you referring to?

However, I've used the camera with batteries but did not run flat. However, I've noticed when I used external component such as a Manfrotto LANC for Zooming in/out.

The batteries goes down very fast, to a point where I no longer trust the battery icon on the LCD camera.

[Adam Welz]

yes, Daniel, you are.

I have updated my blog post with notes on an experiment I conducted around the camera's ability to assess remaining battery life with an NP-F570 battery.

The results so far are worrying and indicate that the NX5 cannot estimate remaining battery life on Sony InfoLITHIUM batteries at all accurately, and give very little warning prior to low battery shutdowns.

Has anyone else had this experience? Please comment here or on my blog post.

Very short low battery warning on Sony HXR-NX5U with NP-F970 and NP-F570 batteries Adam Welz's NXCAM Blog

Cheers

Adam

[Ron Evans]

Adam, the estimate of remaining time cannot include zooming or auto focus activity so will never be correct if camera is stopped, started and zoomed, OIS and in auto focus. On playback it is reasonably accurate if it is like my other Sony's since there is little other power use to effect the estimate. I have to admit that on my FX1 and other Sony's I don't let them get down to less than 30 mins left!!!! I have been using NPF970 on my FX1 and the FH1000 on the XR500 and SR11 and these will run the cameras for over 4 hours and they seem to respond in much the same way.
I will do my first longer real shoot on my NX5U on Monday evening so will report back if it is any different to my FX1 experience.

Ron Evans

[Shaun Roemich]

Forgive someone unfamiliar with the NX5U for weighing in here but as someone with TONS of experience with 960/970 batteries, what I CAN tell you is that the last "hour" of run time is where I would consider the "gas gauge on empty". This from experience with DSR200's, PD150/170's, Z1u's...

60 minutes equals "empty" in my book. At that point, change it when you can.

[Cristian Adrian Olariu]

Adam, I have one question: did you formatted the batteries?
I don't have enough experience with this, but a few people told me that the batteries must be formatted before proper use. I heard a few variants of formatting, charging 24 hours x 2 times, 12 hours x 3 times, 14 hours x 3 times. I chose the last one, but frankly I didn't found anything about that in the camcorder's operating manual or the instruction of the batteries (970).
Just a few hours ago the battery went empty, on the screen appeared "5 min" and then has shut down in a few seconds. but I wasn't in Rec mode at the time.

[Ron Evans]

I put new Sony batteries on charge for 24 hours. Can't remember where I read or was told that but that is what I do now. Also agree with Shaun most of the time I have finished recording before the 970 is showing an hour left. For an evenings performance it is usually still showing 3 hours left on my FX1. Will see how it performs with the NX5U tomorrow.

Ron Evans

[Adam Welz]

the 25 min to zero in a few secs on the NP-F570 had me worried!

As for battery formatting or battery conditioning, I thought one did not have to do that any more?

Cheers

Adam

[Adam Welz]

I mean, isn't it impossible to charge an NP-F970 for 24 hours? Doesn't the charger cut all power to the batt when it's full?

Adam

[Marty Welk]

i might be able to shed some light on it.
have you ever had a camera that DID show the exact minutes of a "info" battery corretally ? or a laptop that told the whole truth about the battery it was riding on?

"format the battery" the curcuit in there works about like this. when you last charged/discharged the battery it got a Fair idea as to how many MiliAmps of capacity it has in it, when your discharging the battery , the ammount of miliamps (per hour) it is using are used to calculate ABOUT how much longer the battery will run, TO a certian voltage.

because all li-ion batteries lose power holding capacity over time, and over cycles, the battery really doesnt know squat EVER anyways.

then you have a camera here that probably requires a bit more initial voltage and slightly more total power, and the battery is pretty much lost, but not much more than they ALWAYS are anyways :-)

a li-ion battery has a graph to it also, where the voltage starts taking a dive neer the end of the discharge, Plus this discharge capacity is effected by the total miliamps used at a time. with more consuption the battery voltage would drop earlier.

if you want your "info" battery to know something, you take it through a full discharge cycle (preferably IN the device your going to use it) and a full recharge cycle, then the brain internally there can assume some of its Capacity information again to work off of. (aka format the battery) you will of course be loosing small ammounts of capacity to put another cycle on it , and have it know more about where it is at.

and a few months later and a few uses later, depending on the AGE of the battery , the temperatures, how well balanced it is internally, and the consumption, it tries again to guess the minutes you have left based on the consumption at that moment. and will be wrong again.

Age: Cheap li-ion china replacment type li-ion batteries (or Clones) often only last 2-4 years before they are completely useless, a good sony battery can last 5-9 before it wont even run that camera for 10 minutes. so how old the battery is can effect the "INFO" severly.

Cycles: cheap ones (or Clones) sometimes make it only about 50 cycles, good sony cells can make it about 500 cycles max, and because the pack isnt fully balanced they have other issues before then. temperatures, and charge cycle type, and storage methods, and all that stuff can effect the number of cycles and capacity by lots.

if you were at 25 minutes, ya shoulda changed the battery.

yes, a good li-ion charger charges up to about 80% quite quickly, within 1-2 hours, then goes into the slow CV rate charging where it slowly finishes up. At a certian low Current rate in the CV phase the charger STOPS charging completey.
this is the proper method for li-ion batteries, and sony generally uses the proper method, even if many other things dont. the things that dont can actually take a lot of life off a battery. improper storage voltages can take time off a battery when it is not even in use.

so generally speaking unless it is a nice new real OEM sony battery, and has been "recalibrated" , it will always show a little less than what it HAD in it last time it knew anything about itself.

[Cristian Adrian Olariu]

In the operation manual it says "If you continue charging more 1 hour after the charge lamp turns off..." so maybe it charges continuously. On the other hand I think the battery would have some instructions in the package if it were the case.

[Vito DeFilippo]

Originally Posted by Marty Welk

Age: Cheap li-ion china replacment type li-ion batteries (or Clones) often only last 2-4 years before they are completely useless, a good sony battery can last 5-9 before it wont even run that camera for 10 minutes. so how old the battery is can effect the "INFO" severly.

Cycles: cheap ones (or Clones) sometimes make it only about 50 cycles, good sony cells can make it about 500 cycles max, and because the pack isnt fully balanced they have other issues before then. temperatures, and charge cycle type, and storage methods, and all that stuff can effect the number of cycles and capacity by lots.

Marty, this sound logical, but where do you get this info and these numbers? Is it a best guess based on your experience, or do you have some source? I was always curious why the generic batteries were so bad...

[Ron Evans]

I use the Sony AC-VQ850 to charge my batteries. This has an LCD that shows charge level, time to charge and time to FULL charge. The charge time difference on an empty 970 between charged and full charge is over another 2 hours charge time!!!. I don't know what the charger that comes with the NX5U does. I likewise charge my NP batteries on the AC-VQH10 which shows the same information. The instructions that came with the 970 when I bought it with my FX1 ( must be 5 years ago now) said to first charge it for 24 hours. I have adopted this approach on all the Sony batteries ever since with good results so far.

Ron Evans

[Marty Welk]

Originally Posted by Vito DeFilippo

Marty, this sound logical, but where do you get this info and these numbers? Is it a best guess based on your experience, or do you have some source? I was always curious why the generic batteries were so bad...

Source 20 years , and over 250 Cells later. Cheap but effective electronics testing equiptment.
i recondition (only) my own packs, and have many totally crasy li-ion projects , like a solar li-ion testing project that has 150+ cell items in it.
plus info from a few forums that do batteries a lot.

not expert, reality survivalist.

[Vito DeFilippo]

Thank, Marty. Great info.