heart rate error when paired with garmin fenix and HRM-dual

[tannere]

Hi, 
I have a concept2 rower with PM5. The Garmin devices I use are the Fenix 6X Pro and HRM-dual chest strap.

When I pair the HRM to the PM5, and initiate a workout both on the PM5 and my Garmin watch (row activity), the heart rate displayed on my watch and the PM5 are completely inaccurate. It always shows my heart rate steadily increasing until it reaches 199bpm over a 10min time period, then over the next 10min it steadily decreases until it finally reads accurately.

What is going on here? I have tried pairing the PM5 to the HRM-dual using both options that appear on the PM5 (it shows up as HRM-dual, and also as ANT). Both initially display the proper heart rate when I am pairing, but as soon as I start the workout on the PM5 and the Fenix 6X, the inaccuracies begin.

Can anyone please help me sort this out?

Thank you!

[Slothful1]

Unfortunately don't have a solution for you, but just wanted to comment that I had similar issues last year with the HRM-dual strap. I checked a few online resources and there seemed to be issues with synthetic shirts causing odd readings. Trying different shirts didn't make a difference for me though. I also tried cleaning the contact points really well before each use, but it didn't make much difference.

In the end I bought a Wahoo Tickr, and generally haven't had an issue with that (connected to BikeErg PM5, Garmin Forerunner 935 watch and Zwift on laptop). Sometimes it goes down to a low reading near the start, but eventually picks up the correct rate later.

Funny enough I had to use the Garmin strap again with my rower earlier this year, when the Tickr was giving funny low readings. Garmin worked perfectly on that session. Who knows? Maybe removing the battery for a while and replacing might reboot the strap in some way, and solve the issue?

Dave

[tannere]

Thanks for the reply Dave!

Interesting idea about the synthetic shirts, I'll give that a go but it seems funny since that is basically all workout gear.

I'll try the battery change as well.

You would think these things would be fool proof by now.

[Tsnor]

FWIW polar h10 belt gave flawless HR on both PM5 and Polar beat app using the H10's dual Bluetooth capability.

Optical watch sensors are spotty. My fitbit charge 3 optical watch is useless. Some people report good results with apple watches. Haven't seen anything for fenix.

Where are you getting the HR signal that is bad? From the belt? Or from the Fenix 6X Pro ? You sure you are getting it from the " HRM-dual chest strap." vs the Fenix optical ?

[HowardF]

How I do it for my Garmin Fenix 6x Pro solar

1- Connect the Garmin HMR ( run 4) to PM5 via " Connect Heart rate and then verify
2- Connect the app ErgData to PM5
3- Select Indoor rowing in Garmin Fenix and wait to start before the HMR ( run 4) is connected to the watch.
4 -Start rowing

[Joebasscat]

FWIW polar h10 belt gave flawless HR on both PM5 and Polar beat app using the H10's dual Bluetooth capability.

Optical watch sensors are spotty. My fitbit charge 3 optical watch is useless. Some people report good results with apple watches. Haven't seen anything for fenix.

Where are you getting the HR signal that is bad? From the belt? Or from the Fenix 6X Pro ? You sure you are getting it from the " HRM-dual chest strap." vs the Fenix optical ?

I’ll second Tsnor’s comment on the Polar h10. And the negative report on Fitbit. Fitbit matches my H10 pretty well at lower rates but hit or miss on the high rate stuff. Mostly miss.

[tannere]

FWIW polar h10 belt gave flawless HR on both PM5 and Polar beat app using the H10's dual Bluetooth capability.

Optical watch sensors are spotty. My fitbit charge 3 optical watch is useless. Some people report good results with apple watches. Haven't seen anything for fenix.

Where are you getting the HR signal that is bad? From the belt? Or from the Fenix 6X Pro ? You sure you are getting it from the " HRM-dual chest strap." vs the Fenix optical ?

Signal is coming directly from the HRM chest strap, as I link that to the PM5 and can see the heart rate appropriately showing up on the screen before I select the device. Though, I how do I know if it's connecting to the strap and not my watch? All I see is "ANT 1234" or some combo of digits. Once in a while I do see "HRM-dual" show up instead of the ANT, and sometimes both. Is there a way to tell which device the PM5 is connecting to?

[tannere]

How I do it for my Garmin Fenix 6x Pro solar

1- Connect the Garmin HMR ( run 4) to PM5 via " Connect Heart rate and then verify
2- Connect the app ErgData to PM5
3- Select Indoor rowing in Garmin Fenix and wait to start before the HMR ( run 4) is connected to the watch.
4 -Start rowing

Thanks for your ordered procedure, this is exactly what I have been doing in sequence! And I assume you have had no issues based on your reply.

[HowardF]

Correct, no issues.

[iain]

Personally I don't have a PM5 so am using a Polar OH1 and Polar Beat and not had any issues. That said as a skinny I can see my pulse with my eyes when I have been rowing hard so the optical really isn't challenged. Those with deeper vessels and more hair are challenging them a bit. I did have lots of drop outs when using an HR belt! So its not one size fits all!