Libre sensor activation issue

[JustSemyon]

Hey everyone!

Here's the thing: I'm trying to start using Freestyle Libre with Miaomiao transmitter for glucose monitoring.
Generally I want not to use the reader at all, but to use Glimp-S phone app for sensor activation and then to monitor everything via Miaomiao.
My Miaomiao hasn't arrived yet, so I figured I'd start using Libre with my phone's NFC to read data.

So I've installed my first Libre sensor and immediately ran into a problem.

I try to activate the sensor with Glimps, and it indeed seem to work: apps like Glimp are able to read the sensor (with totally irrelevant result though, it always shows 0.1 mmol/l) and Liapp shows "Sensor is ready in XX minutes".
The problem is that after about 8 minutes (and this time is always the same) the sensor fails to be read again: all apps show that it is not activated.
If I try to activate it again, the same thing happens.

The main question here is: do you think this is a faulty sensor, or is there a problem with the way I interact with it?
I have some more sensors to try, but I'm afraid to waste some in case the problem is on my side.
And I also failed to find anyone else describing exactly the same problem yet, so has anyone here experienced this?

 

[Antje77]

I'm not sure, but don't you need the LibreLink app to start a sensor?
@Mel dCP , didn't you use the MiaoMiao?

 

[LooperCat]

I do use the MiaoMiao but I start the sensors with first my scanner and then my phone using the Libre app. That way I’ve got the backup of the scanner if I mislay or forget my phone. I don’t use Glimp as I’m on iPhone and use Spike. @Scott-C may be able to advise.

 

[JustSemyon]

As far as I understood during my "research", Glimp S (This is a separate unofficial app just for sensor activation) is also a way to start sensors, since Libre app is unavailable in my country. They won't be readable by a reader, but this is totally fine since I don't need it.
So anybody here using it, or tried to use it?

 

[Scott-C]

I've installed my first Libre sensor and immediately ran into a problem.

"Sensor is ready in XX minutes".

Hi, JustSemyon, I've not used glimp, so don't know the ins and outs of it, but I see you say this is your first sensor today and it's saying sensor ready in xx minutes.

The sensor has a 60 minutes "warm up" time and you won't get any readings out of it until that time is up.

 

[JustSemyon]

Yup, I know that. The trouble is that it gets down to about 52 minutes and that's it: "Sensor not activated" since then forever.

And this is why I am in doubt now regarding what is actually happening. It seems like sensor starts its warm up, but quits it.. or resets completely, or something.

Also, here's one more question for anyone who used Glimp, hopefully there is someone here . It can read a sensor before the warm up time is up, right? Does it get at least remotely correct values in that time period, or it reads the kind of garbage I get?

 

[Cobia]

Yup, I know that. The trouble is that it gets down to about 52 minutes and that's it: "Sensor not activated" since then forever.

And this is why I am in doubt now regarding what is actually happening. It seems like sensor starts its warm up, but quits it.. or resets completely, or something.

Also, here's one more question for anyone who used Glimp, hopefully there is someone here . It can read a sensor before the warm up time is up, right? Does it get at least remotely correct values in that time period, or it reads the kind of garbage I get?

Ive used glimp to read sensors for about 3 years. It dosnt require the 60 min warm up or settling in period to start getting readings. xdrip+ is the same.
with the miao miao now i use the reader to activate the sensor chuck on the miao miao blutooth does the rest.

What phone are you using? According to debeeit some phones nfc dosnt do sensors any good....

Even tho i use a s7 and keep getting warnings i havnt seen what you describe in the first post....

Before you say sensor is stuffed try another breed of phone to read it.

 

[JustSemyon]

It seems like I got it figured out.
The problem was, I think, that the sensor itself (that part in the middle which holds a hair that goes into skin) wasn't making a good enough contact with a measurement/transmitter part (the big white round thing). I guess I didn't press it hard enough when connecting two parts together prior to the installation, or something like that.

Short story long: I've took a bath and decided to try to install a new sensor. I also started the old sensor one more time before installation, just because I could, I guess.
So I've removed the old sensor, installed a new one, started it, and it worked just fine.

There was a surprise, though. When I've scanned the old sensor, it also showed that it had passed that point where it was getting stuck before. What, I think, has happened, is that the water shorted out those bad contacts enough for it to continue going. I wiggled the middle part and it indeed went farther in.
So it is likely, it seems, that it actually wasn't making an electrical contact and a watertight seal around so the water got in.
Anyway, the old sensor finished its 1 hour timer and started measuring air just fine, and it still works.

So apparently what I saw is what would happen if a new sensor is started without connecting two parts together. It does not see the "hair" and resets itself after 8 minutes.

Thanks a lot to everyone responded! I'm glad that this puzzle is solved, even though now I feel sad for wasting essentially a perfectly good sensor.

 

[Scott-C]

Hi, @JustSemyon , I've just rembered that a poster, I think it might have been @evilclive figured out that if you take apart the application device and get the insertion needle (do this carefully - the needle is still slightly spring-loaded and comes shooting out like an arrow!) you can reapply the sensor manually by sliding the insertion needle through it and just poking back in.

Hopefully this won't happen again, maybe just bad luck it happening with your first, I'm on about my 80th now and they've pretty much been fine.

Don't want to put you off glimp if it's what you're familiar with, but when the mm arrives, another option is the android app xDrip+. Been using it for about 18 months now and it's sound.

https://github.com/NightscoutFoundation/xDrip/releases

I'd recommend Sugar Surfing by Stephen Ponder and Beyond Fingersticks by William Lee Dubois, couple of quid on kindle. They really helped me get the most out of cgm when I was starting out with it.

Good luck with it all - cgm has massively improved my T1 life!

 

[JustSemyon]

What, I THINK, can also be done in such situation if it ever happens, since the middle part is basically accessible when a sensor is installed, it could be gently pulled upwards with the tweezers that are thin enough and grippy enough. So hopefully everything snaps into place after that procedure.
Obviously I've never tried it and I hopefully never will, just a suggestion that it might be a way to fix it.

@Scott-C, I'm not really familiar with anything since I'm just starting.. But I've tried several apps and already ended up using xDrip+, with which I'm very happy.
I will definitely check out those books you've mentioned. I'm two days into CGM now and it already feels like an enormous improvement.
Thank you very much for your suggestions, they are really helpful!