Inaccurate Heart Rate

I got my watch about 2 weeks now and so far BPM looks good. During my workouts it goes above 140 BPM and I saw even 200 BPM. I'm not sure if they are correct measurements but looks good to me. Also it detects automatically my activity. I mean when I do warm-up or play soccer it detects activity automatically so I believe it works well. The only thing is that sometimes it takes some time to get measurement. I think it can be related to wet hand. 

Another small issue is that 2 times so far I had to restart app to synchronize data with my watch. I use iOS version. 

I bought an early Scanwatch - my second Withings watch - and the heart rate data is frustratingly inaccurate. Often shoots up to rates well above my maximum - which was a little terrifying at first.

I've checked with a chest-strap monitor and it shows the Scanwatch is simply wrong, often 60-80bpm too high. And the error intermittent, so potentially dangerous.

The older watch was much more accurate.

It largely negates the point of having the watch at all. 

jshallcross - me too (heart rate way too high) - did you get a solution? I have asked Withings for assistance.

Nothing yet. I'll keep you posted.

Check this out : 

https://www.youtube.com/watch?v=KjemOE2eHcY&list=LL&index=18&t=280s

The tester on Youtube - has the same problem - it's a very scientific approach - worth watching - the product is faulty  

Same issue here. I’m doing indoor cycling, and when the HR reaches around 120-130, it jumps on 50-60 and stays there until my HR drops to around 100. Then it starts showing the real value. Definitely some bug somewhere. Overall, it makes my Scanwatch completely irrelevant in this respect (HR monitoring when doing other sports where I cannot use a dedicated chest strap). Now, I wonder how about the other sensors on the watch, whether they show real data, or some completely wrong data...

PS: I'm also using a Polar chest strap while on cycling, so I can see the actual HR, therefore, I can compare.

The same for me

This received from Withings Support:

Hello,

Thank you for reaching out to us. I'm sorry to hear that you're receiving inaccurate measurements from your ScanWatch. Let me help you with this.

I truly appreciate you for providing the additional information as it helps me to isolate the issue further.

I understand that you might aware and familiar with this, however, to ensure that heart rate is properly measured, the watch should be worn about one centimeter behind the wrist bone. Additionally, the watch should be worn so that it is comfortably tight. There should be no gap between the back of the watch and your skin. Please adjust the watch accordingly and let me know if the heart rate is now accurately measured.

Note that using a metal or leather band could result in a minor heart rate inaccuracy as it may not be worn as tightly as the included fluoroelastomer band.

If the measurements are still not accurate, please let me know if they are too high, too low, and by how much they are inaccurate.

Please note that other factors can prevent heart rate measurements from being accurately, or at all. Please follow this link for more information.

Best regards,

Grace

I've changed the strap and it's a little better but still shows dramatically high readings on occasion.

I keep the strap as recommended. I just stay on the indoor bike/trainer and paddle. The hand doesn’t move. Regardless if I start a program or not on the watch, the BPM drops to 50-60 as soon as the real BPM reaches around 110-120 (as observed by the chest strap). Then it goes back to normal when I finish paddling and the HR goes back to around 80 or so.