Ming the Merciless
There is no mercy
- Location
- Inside my skull
Have you found that you are also pedalling slower and barely breathing?
Heartrate monitor reading low..
- Thread starter wafter
- Start date
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Bristolian
Well-Known Member
- Location
- Bristol, UK
The instruction leaflet that came with my Powrlabs chest HRM (the type that clips onto an elasticated strap) says that you should always remove the monitor from the strap after every ride and wipe the contacts to remove any residual sweat or the readings can become erroneous over time.
HLaB
Marie Attoinette Fan
My H10 was doing that, particularly if I was riding into a cold wind. I've tightened the strap and its been 95% good. It works best when its under a tight fitting gabba, or under more layers or after 5mins of sweating when uncovered on the turbo. It occasionally reads low still but every time I think about replacing the strap it comes good. I probably will get round to a new strap at some point but I'm not in too much of a rush.
Thanks - seems to me that it's probably due more to a poor interface between the strap and skin; rather than a problem with the strap itself..
Seems with enough of a tonguing it works reliable; while unfortunately my expanding circumference has done a pretty good job of tightening the strap
Bit of a late update having gone down this rabbithole a bit more as the device continues to misbehave.
Sadly plenty of anecdotes on the net about the H10 being unreliable, which is both sad and surprising considering they've generally had good reviews and mine has been flawless for the vast bulk of the 6yrs / 10k miles / 800hrs of service it's given.
I checked my ride in from last Monday and in the middle of a medium-exertion ride where I was consistently doing around 14mph, my measured HR dropped as low as mid-20s; which of course is ridiculous considering my resting HR is typically around 50.
There have been many (apparently unsuccessful) suggestions for causes / remedies - dry or dirty strap on contact face with skin, dirty or corroded terminals, poor battery connection... Last night out of desperation I cleaned the inside face of the strap with isopropanol, along with the contact buttons on the strap and HRM itself (no signs of corrosion, a little filth on the base of the terminals on the HRM but I suspect this was irrelevant given the amount of contact area available).
The battery was removed, left out and re-inserted with the part of the battery that contacts the outer terminal pushed in first, so that it had an outward / radial component rather than going straight into the device (in case this was causing some contact issue).
Fingers' crossed it behaved itself on the way in today, but I'm not holding my breath.
I'm both irritated and intrigued by this problem and would like to investigate it more but it's all pretty sealed, while I lack the understanding of how it works to really probe it further. One assumes it's a problem with the measurement side rather than the bluetooth transmission to the device. I know it works by logging electrical pulses, so perhaps it has some kind of wheatstone bridge to measure this voltage fluctuations..?
When I can be bothered to drag out the toolbox maybe I'll give all relevant bits a poke with the multimeter and see where that goes. So far Polar "support" are proving worse than useless..
Sadly plenty of anecdotes on the net about the H10 being unreliable, which is both sad and surprising considering they've generally had good reviews and mine has been flawless for the vast bulk of the 6yrs / 10k miles / 800hrs of service it's given.
I checked my ride in from last Monday and in the middle of a medium-exertion ride where I was consistently doing around 14mph, my measured HR dropped as low as mid-20s; which of course is ridiculous considering my resting HR is typically around 50.
There have been many (apparently unsuccessful) suggestions for causes / remedies - dry or dirty strap on contact face with skin, dirty or corroded terminals, poor battery connection... Last night out of desperation I cleaned the inside face of the strap with isopropanol, along with the contact buttons on the strap and HRM itself (no signs of corrosion, a little filth on the base of the terminals on the HRM but I suspect this was irrelevant given the amount of contact area available).
The battery was removed, left out and re-inserted with the part of the battery that contacts the outer terminal pushed in first, so that it had an outward / radial component rather than going straight into the device (in case this was causing some contact issue).
Fingers' crossed it behaved itself on the way in today, but I'm not holding my breath.
I'm both irritated and intrigued by this problem and would like to investigate it more but it's all pretty sealed, while I lack the understanding of how it works to really probe it further. One assumes it's a problem with the measurement side rather than the bluetooth transmission to the device. I know it works by logging electrical pulses, so perhaps it has some kind of wheatstone bridge to measure this voltage fluctuations..?
When I can be bothered to drag out the toolbox maybe I'll give all relevant bits a poke with the multimeter and see where that goes. So far Polar "support" are proving worse than useless..
Last edited:
presta
Guru
I have two Polar monitors and M52 and an FT4, but I don't have any experience of the new ones that operate with a smart phone. The M52 had a plastic belt that you threw away when the battery was flat, and the FT4 had a replaceable battery in a transmitter that clipped onto a fabric belt with wire gauze contacts woven in.
The old plastic ones were far more reliable, in fact it took so little time to wear out the contacts on the fabric one that it worked out cheaper to throw away plastic belts than replace batteries and worn out belts on the new one. Newer ones may be improved.
Both of mine are susceptible to interference, power lines, passing trains, and a local radio mast all interfere with it, but I quickly got to know what to expect where. On mine it usually takes the form of reading ~230bpm, but it may have a different effect on newer Bluetooth devices.
Then there's my arrhythmia, which had various effects: usually it would read high, but sometimes it would switch up and down at random. It quickly became obvious that it wasn't interference, not just because it wasn't in familiar places, but also it persisted for hours, not just a few seconds whilst passing under power lines. At first I assumed it was a faulty monitor, and stopped using it, but when I bought the FT4 and found that was the same the penny began to drop.
The old plastic ones were far more reliable, in fact it took so little time to wear out the contacts on the fabric one that it worked out cheaper to throw away plastic belts than replace batteries and worn out belts on the new one. Newer ones may be improved.
Both of mine are susceptible to interference, power lines, passing trains, and a local radio mast all interfere with it, but I quickly got to know what to expect where. On mine it usually takes the form of reading ~230bpm, but it may have a different effect on newer Bluetooth devices.
Then there's my arrhythmia, which had various effects: usually it would read high, but sometimes it would switch up and down at random. It quickly became obvious that it wasn't interference, not just because it wasn't in familiar places, but also it persisted for hours, not just a few seconds whilst passing under power lines. At first I assumed it was a faulty monitor, and stopped using it, but when I bought the FT4 and found that was the same the penny began to drop.
