This discussion has been locked.

You can no longer post new replies to this discussion. If you have a question you can start a new discussion

Continuous HR registration from external sensor possible?

From another thread:

The auto option is there so that when an external HR is connected, that will be used instead.

I assumed that an external HRM would override the built-in optical HRM outside activities just as it would during activities, but that is not the case in version 6.00 and 6.75. Unless the HR widget is active, no HR is registered from a connected external HRM.
Is there a way to enable continuous HR registration outside of activities from an external HRM? (For example when not wearing the watch at night and using a different OHRM for RHR monitoring during sleep).

0 Former Member over 7 years ago

It appears I was wrong about the OHR data being stored in lieu for the HR data from the connected Tri strap (ie before selecting 'Download HR Data').
However I needed the above tests to prove this.
If I stop and Save a Run activity (for example) and look at the details then immediately (within a minute or so) select the 'Download HR Data' option I always see a change in the details eg Calories and Training Effect. Sometimes the TE changes are significant.
Try it; it is easy to do with a 935.
My assumption (incorrect but reasonable I think) was that before 'Download HR Data' was selected the HR data used must have contained OHR data because TE data is influenced by recorded HR data.
The delay (after stopping the activity) in downloading data from the Tri strap is irrelevant.
I only needed the delay in the tests above to allow me to get to a place to download the two instances of the activity on GC.

After stopping a Open Water activity the watch automatically searches for the Swim strap and downloads the HR data.
It probably does this for a Tri strap too, but I have not tested it.
Why are the other activities (eg Bike and Run) different from Open Water? Who knows.
I agree there is a need for the 'Download HR Option' just in case the watch and the strap are separated from each other when an activity is stopped and Saved.

0 timgrose over 7 years ago

> Why are the other activities (eg Bike and Run) different from Open Water? Who knows.

Because in the water HR can't be continuously relayed to the watch so the default behaviour then is to do the download HR.

0 alexpez over 7 years ago

I've noticed the same thing happening over the past week (previously owned a Forerunner 610 with HRM chest strap). The TE values change significantly (5.0 to 2.9) only after I select Download Heart Rate despite being paired with the HRM-Tri before I set out and start the Run activity (watch tells me it is paired and doesnt give me any indication it loses that pairing during the run).

Do I need to be selecting Download Heart Rate after completing a Run activity?

Is there an indication when in a Run activity that the HRM-Tri isn't connected (I haven't seen one yet)? I am seeing "HR-0 Connected" when I choose the Run activity (which I have just renamed to HRM-Tri)

Watch is on v6.10.

Something else that I was wondering about is why are both the HRM-Tri and HRM-Swim that are packaged with the 935 Tri Bundle named "0" (that is how they appear in my 935)?

0 Former Member over 7 years ago

Hi Alex,
A very good question you ask about the "Download Heart Rate" option.
I have been trying to get to the bottom of this and have finally decided to contact Garmin support for an answer; been waiting for 7 days now.
With the Tri strap it shows connected at the start of a Run activity and when you save the activity you can then execute "Download HR".
Do you need to do this after every activity and if not what indicators are there that tell when you should not do this?

You can always only download once from the strap after an activity and I always find data changes eg Calories and Training Effect.
Sometimes the changes are significant.

Supposedly (I've been told) if the strap connects at the start of an activity and remains connected all the data goes to the watch.
There should then be no need to execute "Download HR".

Executing the option and finding data changes implies (to me) that the connection with the strap during an activity is unreliable ie connection is often lost.
Alternatively there is something else going on ie additional data being downloaded.

I would imagine that during at least one of my run activities the watch would have remained fully connected to the strap.
But after downloading HR data the activity data always changes.

With the 935 my straps (Tri and Swim) have a 6 digit serial number.
When selecting an activity I get "xxxxxx Connected".
Maybe your straps have been renamed.
Check Settings>Sensors and Accessories; in this menu you can find previously connected straps.
You can then select a strap, check its Id, status, rename it etc

0 alexpez over 7 years ago

It is confusing. The user guide says that "The device automatically uses the wrist-based heart rate monitor unless you pair an ANT?+[SUP]®[/SUP] heart rate monitor to the device." Well, I paired and ran with the HRM-Tri, had notification that it was paired, didn't receive notification that it lost connection at any point, and started and stopped a Run activity, and the TE values were one value before I selected Download HR, and a very different value after I selected Download HR.

I've just done two small 3km test runs wearing the HRM-Tri, and seen the TE values change following a download despite wearing the watch and strap and not receiving notification that the pairing failed at any point.

Procedure from me (watch on left wrist, HRM-Tri on):
1.From watch face click START-STOP
2.Choose RUN activity
3.Wait for GPS to go green
4.Wait for HRM-Tri connected to display
5.Click START-STOP to start run
6.Run for 3km
7.End run by stopping and clicking START-STOP
8.Click SAVE - screen says saving and displays stats
9.Click DONE

This would then present me with the stats from the run, including TE.

The first run gave me values of 2.8, and 0.0. I then selected DOWNLOAD HEART RATE, had a message say "Searching for Stored HR Data", "Downloading Stored HR Data", and then "Processing Downloaded HR Data". "HR Data Download Successful" was then shown across the centre of the screen at the same time as a message saying "HRM-Tr Connected" (not enough space for HRM-Tri to be printed to screen) along with a heart icon. The TE values changed to 1.3 and 0.4. At no point during the activity was I made aware that the strap and the watch were no longer communicating. The watch notified me that it was connected before I started the run.

The second run did the same thing - TE was 3.0 and 0.3, then I selected DOWNLOAD HEART RATE, had a message say "Searching for Stored HR Data", "Downloading Stored HR Data", and then "Processing Downloaded HR Data". "HR Data Download Successful" was then shown across the centre of the screen at the same time as a message saying "HRM-Tr Connected" along with a heart icon. Going into TRAINING EFFECT then presented me with values of 1.0 and 0.8.

Am I doing something wrong? Should I be pairing the HRM-Tri in a specific way that I'm not doing (currently wetting it, putting it on, going into the list of activities and choosing Run, then waiting for it to say GPS and HRM-Tri Connected).

If it is losing the pairing during the run, should the watch be notifying me (not currently)?
If so, how?
And is there anyway to check at a glance whether the HRM-Tri is still paired during a run activity?

Does the watch mark HRM-Tri data differently from OHR data so we can tell what was used to record the data?

0 tmk2 over 7 years ago

And is there anyway to check at a glance whether the HRM-Tri is still paired during a run activity?

Look at the green LEDs of the optical HR. They should be off when an external HR sensor is connected.

0 alexpez over 7 years ago

Is the watch supposed to alert the wearer when it loses the connection?

I have a run planned in an hour - today I will manually disable the Wrist Heart Rate (under Sensors and Accessories) and wear the HRM-Tri, and see if 1.I see HR data on the watch during the run from the HRM-Tri, and 2.selecting Download Heart Rate following the run alters the TE again.

0 Former Member over 7 years ago

I tried a quick experiment.
I started a Run Activity (indoor walking really) with the Tri strap connected.
Sure enough the WHR leds were off when the strap was connected.
Next I took the strap off and had to walk some distance (to another room) for a disconnect.
Sure enough the WHR leds came on and HR data was from the WHR.
I am assuming the HR data was from the WHR; the watch is currently incapable of indicating the source of the HR data on the display at present.

I connected and disconnected the strap a few times during the activity and repeated the activity twice.
Each activity only lasted a few minutes.

There was an interesting operation of the watch that I noted.
When I stopped and saved the activity while the Tri strap was NOT connected the watch acted like it had finished a Swim Activity ie it automatically started searching for the Tri strap.
I moved close enough for the watch to make contact with the strap and data was exchanged.
However if I stopped and saved the activity when the Tri strap was connected then we are back to the usual operation.
That is do I execute the "Download Heart Rate" menu option or not.

My testing was only brief.
I believe that Garmin is responsible for any exhaustive testing; ideally before product release.

0 tmk2 over 7 years ago

I'm not sure I understand, but I think the watch behaviour described in your last post is correct. This is how I would expect it to behave.

0 Former Member over 7 years ago

If the watch behaviour described above is correct (and I believe it is inconsistent/wrong) then why doesn't Garmin document it in the user manual.

Tmk2 please get a 935 watch use a tri strap and when you Save the activity let me know if you select "Download Heart Rate".
Then tell me why you made your choice?
Notice if you choose "Download Heart Rate" your training details will change.
Why do the details change?

Don't get me wrong I am on Garmin's side and want them to have a superior product.
I am starting to have trouble hiding my frustration.