Power Reading Zero while riding
I apologize if this is covered somewhere in the wiki or in the webinar (which I am desperately trying to get through). I have had a power tap for about 2 months head unit is my 310XT. I don't seem to have any problems with it. I get on and ride, it recognizes the PM right away and off we go. I calibrate probably once/week.
I noticed on my last test that the WKO+ file showed the power at 0 a few times. This is when I know I was working hard. It is a quick dip and then back up again. I noticed it on my ride yesterday on the 310XT readout as well. I don't have time to download my workouts all of the time to look at the graphs so this may have been happening all along but I don't think so. I know the power #s fluctuate but it is heartbreaking to be pushing hard and for the PM to say 0.
Any suggestions? Is this normal?
Comments
Could there be any other device interfering electronically?
When I rode with Leigh and Dave Boyle, Dave's Quarq really messed with my PT reception.
If the 310XT is closer to the hub, perhaps the issue would change?
I can't remember which PM had issues with the head unit being just centimeters too far away, but I did read about it.
Hope someone else has ideas.
All of this may or may not be the explanation but here is my experience. I had this happen once about a month and a half ago while riding the trainer. I realized my wheel size was set to "auto" instead of custom because up to that point I had been riding outdoors. I assumed that auto meant it was determining my speed from the GPS and that I needed to tell it the wheel size in order for it to calculate cadence (I don't have an external speed/cadence sensor), and in these hub-based power meters cadence is related to power. I changed the wheel size to custom and I didn't have any more zeros.
Then the other day it happened again while riding indoors and I realized I had forgotten to turn off the GPS. I turned it off and the zeros went away.
There are some discussions about this topic in the Garmin forums (google it) and some say it's a firmware problem with the 310, others think it could be interference with the wifi network in your house, and there are still other guesses. Let us know if any of my "solutions" help and maybe we can figure this issue out.
I of course do have wifi in the house. As do all of my other neighbors that I live in very close proximity to. Will check out the garmin forums as well.
I have a few dropout in my rides but I just chalk it up to the unreliability of a wireless device.
Since the ANT+ system works on the 2.4ghz range there can be a lot of interference (wifi, phones, etc.)
If your Garmin is way out on your aerobars it may help to move it closer to your rear wheel, but I can't see this making much of a difference.
If you are having a lot of dropouts I would make sure the batteries in your PT are fresh and if all else fails call Saris.
Just as an aside, if you find you have to have the GPS on to get accurate time/date (i.e. if you do an indoor workout with GPS off and the dates are way in the past), you have a defective 310XT and you should get Garmin to replace it. It's a known hardware issue with some units where it can't maintain time properly without satellite lock, and the only proper solution is to get a different one.
@ Craig, thanks for the heads up. My unit has always worked that way (needing a satellite lock to get time/date) and I assumed that is the way they worked. I am on my way to Disney for Goofy's Challenge but will definitely look into it when I get back.
While in bike mode (not running mode) Go to Settings-Bike Settings-then scroll down to Bike 1 or whichever bike you are using. In Bike 1, go to Bike Details then you'll see the wheel size options.
Garmin has a device discovery "feature" in all of their products, that if you are not aware of can be an issue. For every ant+ add on device you have set to on in the garmin it will try to find that device over and over until it finds it. This is great for use triathletes as you can swim with your 310 and then in t1 it will find your PT on it's own without you having to do anything and then find you footpod in t2, etc.
The downside is each time that this discovery cycle either restarts or thinks that it has found a device (or Satelite if GPS is on and you are inside) the recording of power data seems to drop out for a few seconds.
Before i knew this I often had power drop outs in my files and quarq actually upgrade the electronics pod on my zinqo for free. However I still had a issue, I talked to them again and they explained that to me. Since then every time I have had a drop out it is because I had the HR set to on or the GPS on in the garmin when I was not wearing the stap or inside. This has completely solved the problem for me.
FWIW, I use a quarq, but this issue is the same for PT, SRM, quarq, etc.
I had another issue today. I was warming up and after about 8 minutes I got zeros for power and cadence. I tried to re-scan for the hub, started a new exercise, made sure all the settings were correct, and still zeros. I removed the battery cover, removed the battery assembly, removed the batteries, re-inserted them, reinstalled everything, and it worked fine after that. I think I'll go ahead and replace them though.
I did ride outside for about 30 minutes the other day, 5 of which the power meter worked (it was 35 degrees). I figured it was just cold and sure enough, I came inside for the intervals and it worked fine. In any case, I will replace the batteries ASAP, and thanks for the info.
Ok, I may have some stupid questions here but am having trouble with my garmin 310 and my power meter and am hoping for some help. The garmin people have been zero help. My garmin used to work fine all the time for my power tap inside or out. Recently, it stopped reading my power meter at all and sometimes even said "multiple power meters found" when I was on a computrainer. I didn't even know my power meter had batteries and have no idea how to change those if that is the problem. HELP - any advice would be great. Just don't know if this is a garmin issue or a powertap issue. thank you!! Lisa