Powerpod V3 causing drops in estimated cadence

[Velocomp]

I purchased a Garmin Cadence 2 sensor. I installed it on my crank arm and then I did a sensor pairing with my PowerPod. The new cadence sensor was found; I confirmed this by checking the wireless IDs in my unit..

I did a ride and had no problems with cadence signal.

So, I am stumped.

[droffsite]

Thank you for the followup.

I've since recalibrated and paired without the cadence data going to the PowerPod (also tried recalibrating with cadence: still had a problem). Garmin Connect cadence looks right.

I looked at a few other rides. Looks like T ~= 90 s, sometimes dipping down to ~30 seconds, with typical displayed values between 64-67 (though Garmin Connect shows occasional local minima of 61).

One thing I just noticed: when I recalibrated, I neglected to change the profile to get HiDef recordings. Possibly something there?

[droffsite]

iBike files for above (only 3 attachments allowed?)

[droffsite]

...and also just noticed I can't merge the cadence and heart rate data with one of the non-HiDef files. Is that expected?

...and also realized I don't know how I got HiDef files in the first place.

[Velocomp]

Please post your Garmin file in .tcx or .gpx format.

[droffsite]

Attached (had to zip it as the uploader wouldn't allow .gpx files).

PowerPod not receiving cadence; can't add cadence or heart rate to data in Isaac.

[Velocomp]

Please post the .gpx file where cadence is flaky.

[droffsite]

Attached.

PowerPod receiving cadence; PP reported cadence drops to ~64 periodically.

[Javi SF]

I can confirm that two Wahoo Cadence units, and one Moofit cadence sensor, failed as described, intermittent Ant+ signal or total lost of Ant+ signal. I suspect that the power of the battery has something to do here, when a new one is installed, Powered V3 "readed" the cadence longer, but after a two hour ride, cadence reading failed and started the intermittent readings again, but I have no enough time to keep testing.

This never happens with the Speed Sensor, no matter how long you have ride.

After removing the cadence sensors from my Wahoo Roam and physically from the bike, also removing the battery to reset it and after I have recalibrated the PowerPod V3 w/o Cadence sensor, it finally worked as expected and for what it was bought, as a power meter.

After that I have paired it with me Wahoo Roam, and everything is OK now, correct cadence readings on the GPS unit, and no power drops, finally!!

Sorry for my English.

Javier

[Velocomp]

I can confirm that two Wahoo Cadence units, and one Moofit cadence sensor, failed as described, intermittent Ant+ signal or total lost of Ant+ signal. I suspect that the power of the battery has something to do here, when a new one is installed, Powered V3 "readed" the cadence longer, but after a two hour ride, cadence reading failed and started the intermittent readings again, but I have no enough time to keep testing.

This never happens with the Speed Sensor, no matter how long you have ride.

After removing the cadence sensors from my Wahoo Roam and physically from the bike, also removing the battery to reset it and after I have recalibrated the PowerPod V3 w/o Cadence sensor, it finally worked as expected and for what it was bought, as a power meter.

After that I have paired it with me Wahoo Roam, and everything is OK now, correct cadence readings on the GPS unit, and no power drops, finally!!

Sorry for my English.

Javier

Thank you for your post. What you are reporting is very interesting.

I have a Garmin cadence sensor on my bike and it has worked for years without problems.

I did look at your .gpx data; it did not have any cadence data in it, so I was unable to make any comparison. Perhaps you can post your .fit file; I will open that in Garmin Connect.

[droffsite]

Assuming you're using the cadence for PowerStroke, can you provide a setting where the PowerPod receives cadence but doesn't retransmit? Then the iBike file would have the necessary data and Garmin would get the correct cadence numbers.

Of course I don't know if that's valid, but a thought.

[Velocomp]

Attached.

PowerPod receiving cadence; PP reported cadence drops to ~64 periodically.

I have been reading this entire thread again, this time more slowly...

1) The cadence problem is appearing in the PP ride file. This means that PP is not receiving the data properly, or that the data it's receiving is not being recorded properly

2) I have been unable to find any posts where I can see cadence data BOTH from PP AND from the Garmin. This is important, because that information will establish whether or not the problem is with the cadence sensor.

3) Do you see strange cadence numbers ALSO on your Garmin screen while you ride?

4) PP is not retransmitting cadence data

[droffsite]

(Sorry about the delayed response: Gmail insists on routing spam@velocomp to, well, spam)

1. Check.

2. Do the files I posted above not satisfy that requirement? I posted matched files (from the PowerPod and my Edge, https://velocompforum.com/viewtopic.php?p=29672#p29672) that have the spotty cadence data. If not, I'd be happy to provide whatever you need (just need to know how).

3. When the is PP paired to the cadence sensor, the Garmin shows strange data. When the PP isn't paired to the cadence sensor, the Garmin shows normal data.

4. Above you wrote

When PP is paired with your cadence sensor, PP transmits BOTH power AND cadence signals together in the power channel (this is an ANT+ standard). So, your Garmin is reading the intermittent cadence numbers transmitted by PP.

Is that not the case?

[Velocomp]

(Sorry about the delayed response: Gmail insists on routing spam@velocomp to, well, spam)

4. Above you wrote

When PP is paired with your cadence sensor, PP transmits BOTH power AND cadence signals together in the power channel (this is an ANT+ standard). So, your Garmin is reading the intermittent cadence numbers transmitted by PP.

Is that not the case?

I was incorrect in the above statement. The fact that PP is recording intermittent cadence data in its ride file means that PP is receiving intermittent cadence data, or PP is not correctly recording the cadence data it is receiving.

If I understand your post correctly, you are saying that your Garmin ALSO is recording intermittent cadence data. That would suggest that the problem is in your cadence sensor.

I have identically the same configuration on my bike: Garmin, paired to PP and to Garmin 2 cadence sensor. I am not seeing this problem.

I looked at the .gpx file you posted. It does not have cadence data in it. Please post the .fit version of the same file.

[droffsite]

If I understand your post correctly, you are saying that your Garmin ALSO is recording intermittent cadence data. That would suggest that the problem is in your cadence sensor.

When my PowerPod isn't connected to my cadence sensor, my Edge shows and records a consistent cadence. When my PowerPod *is* connected to my cadence sensor, my Edge shows and records strange cadence data. The same statements are true when using a Fenix 5x. In short, the cadence data looks good when the PowerPod isn't involved.

Just checked: I've done 15 rides since I unpaired cadence on the PowerPod. All have good cadence data on the Edge. Unfortunately I can't merge the cadence data into the iBike files to see PowerStroke data.

I looked at the .gpx file you posted. It does not have cadence data in it. Please post the .fit version of the same file.

Attached.

[droffsite]

I was incorrect in the above statement.

I took a (very cursory) peek at the specs for the ANT+ bike power profile and see that it does in fact allow for sending cadence data (as you earlier noted). What I didn't see was what the payload of the message from the meter looks like.

30 years of software development, however, has me wondering: is it possible that there's a field/record/whatever the ANT+ term for transmitted data is that's got a null or 0 value that might be confusing the head unit? I can't find information on which message wins if multiple devices send the same data (I imagine that might even be vendor implementation specific).

Worst case, once this smoke goes away (can't happen soon enough), I could try a ride with the PP paired to cadence, record on my Edge paired to the PP and cadence sensor, and also record on my Fenix *not* paired to the PP but paired to cadence. Presumably, if the PP isn't a factor, both the Edge and Fenix should have (close enough to) the same values in that case.

[Velocomp]

If I understand your post correctly, you are saying that your Garmin ALSO is recording intermittent cadence data. That would suggest that the problem is in your cadence sensor.

When my PowerPod isn't connected to my cadence sensor, my Edge shows and records a consistent cadence. When my PowerPod *is* connected to my cadence sensor, my Edge shows and records strange cadence data. The same statements are true when using a Fenix 5x. In short, the cadence data looks good when the PowerPod isn't involved.

Just checked: I've done 15 rides since I unpaired cadence on the PowerPod. All have good cadence data on the Edge. Unfortunately I can't merge the cadence data into the iBike files to see PowerStroke data.

I looked at the .gpx file you posted. It does not have cadence data in it. Please post the .fit version of the same file.

Attached.

Your .fit file shows the same cadence problem as the PP file.

So, one of two things is happening:

1) there is a problem with your cadence sensor

2) PP is mis-reading the cadence sensor data, is transmitting that incorrect cadence data by ANT+, and your Garmin is reading the PP cadence data, and not the cadence data directly transmitted by your cadence sensor to your Garmin.

I don't know if PP retransmits cadence data it receives, and I don't know if Garmin will override cadence sensor data it receives directly with cadence data that is retransmitted by a power sensor. Both of these conditions would have to be met in order to have 2) as a possibility.

I will check with our firmware developer.

[droffsite]

Any updates?

[SilasGreenback]

FWIW i have the garmin cadence 2 crank sensor and noticed the same thing when it was paired to my PP. i paired it directly to my edge 1030 and same issue.

I’m fairly sure its something to do with the garmin sensor as i had no such issue with my £10 basic magnet sensor. Switched to a supposed upgrade magnetless and doesnt seem as reliable.

I’ve reset the sensor, tried it with PP left at home and always the same occasional drops to 67 or therabouts.

[Velocomp]

FWIW i have the garmin cadence 2 crank sensor and noticed the same thing when it was paired to my PP. i paired it directly to my edge 1030 and same issue.

I’m fairly sure its something to do with the garmin sensor as i had no such issue with my £10 basic magnet sensor. Switched to a supposed upgrade magnetless and doesnt seem as reliable.

I’ve reset the sensor, tried it with PP left at home and always the same occasional drops to 67 or therabouts.

Are you saying that you see the dropouts even when PP is not paired? If so that is strong evidence that the problem is with Garmin.

It would be very interesting to see if this problem disappears when you return to your magnet sensor. If you can please try this and report back your findings.

[Velocomp]

ALERT: We continue to see this problem with some ride files, and we have confirmed that a Garmin 2 cadence sensor, when paired to PowerPod/AeroPod, does not always provide correct cadence information.

So, this appears to be a bug in our firmware.

We are working on a fix now...

[mir]

ALERT: We continue to see this problem with some ride files, and we have confirmed that a Garmin 2 cadence sensor, when paired to PowerPod/AeroPod, does not always provide correct cadence information.

So, this appears to be a bug in our firmware.

We are working on a fix now...

I have also recently bought a Garmin 2 cadence/speed set for my new bike and can confirm the drop-outs of cadence measures.

[droffsite]

Great news! Finding the issue, not that you gotta fix it.

Thank you for the update.

[lorduintah]

So I finally have an example of this issue.

I have a screen capture of Garmin Connect output from the ride - showing cadence lost at about 36 minutes for ~4 minutes - but power (only coming from PP3) that lasted about 1 minute - so I think there is some evidence that PP3 was seeing cadence ===

However on the Isaac output, at the 36 minute mark, cadence drops to zero for the full ~4 minutes, and power for only about a minute.

Trying to repair the missing cadence in Isaac turns into a mess.

Tom

[SilasGreenback]

Exposed a bug or is the bug?

Not convinced PP is the problem. Here’s my cadence 2 paired directly to my edge 1030. Check out the regular drops. I just think the garmin handles the drops better than PP and hides it better when theres a signal break.

I’m going back to magnets....just as soon as i can find the damn thing in my bike parts stash.

[Velocomp]

This is really interesting information!

This looks like the same problem seen in PP ride files.

Please do a short ride with PP turned off (this way, there is zero chance your Garmin is seeing cadence data from PP). Please post a screen shot showing cadence data from your 1030.

[SilasGreenback]

Will do. Work / childcare so it’ll be a couple of days but will try and get out Thursday for a quick ride.

And just so you know what “process” i did:
1) activate wheel sensor
2) turn on PP and wait for pairing to complete
3) turn on computer
4) turn on HR & Cadence and wait till edge shows “cadence /hr found
5) Go ride!

I havent found a way to deavtivate sensors in isaac and havent done the whole pairing new sensor process to make sure only the speed is paired. Havent given up on Garmin cadence sensor completely. But might do!

[Velocomp]

What we are trying to eliminate is the possibility that your Garmin is displaying cadence data retransmitted by PP. Keeping your PP off during the test ride will accomplish this.

Make sure your Garmin is paired to your cadence sensor!

[colnago1965]

I don't know if PP retransmits cadence data it receives, and I don't know if Garmin will override cadence sensor data it receives directly with cadence data that is retransmitted by a power sensor.

About Garmin ANT+ Sensor Preference (information retrieved from Garmin Edge forum...):
• cadence from the power meter that is sending torque data such as Vector takes priority over cadence from a sensor as the cadence value from the power meter is needed to compute power.
• If the power meter is sending power data (not torque data) then the cadence sensor takes priority as the cadence value from the power meter is not required (by Edge…) to report a power value.

[Velocomp]

I don't know if PP retransmits cadence data it receives, and I don't know if Garmin will override cadence sensor data it receives directly with cadence data that is retransmitted by a power sensor.

About Garmin ANT+ Sensor Preference (information retrieved from Garmin Edge forum...):
• cadence from the power meter that is sending torque data such as Vector takes priority over cadence from a sensor as the cadence value from the power meter is needed to compute power.
• If the power meter is sending power data (not torque data) then the cadence sensor takes priority as the cadence value from the power meter is not required (by Edge…) to report a power value.

This is helpful. It will be important to see some cadence data where PP is "off". But, since PP reports power, not torque, data, if you're correct then the cadence value read by the Garmin is coming straight from the cadence sensor.

We will see...