I recently bought the FR 45 a couple weeks ago. The heart rate appears to be pretty accurate when at rest so far, I'm not sure about how accurate it is during activity as my HR seems a little high at times in the 190's. I went on a few runs and everything seemed to work just fine in regards to the HR monitor. The last 2 runs I went on, almost immediately at the start of my run and occasionally throughout the run I randomly get "Heart Rate 255" . I assume the 255 is what it thinks my HR is at the time, but when I close out of the alert and look at my HR on the data screen, it's usually around 150-180 or whatever it is at the time. After my run, I look at the HR screen on my phone and it doesn't appear my HR ever went above 200 at any time during the run. I do have the Abnormal HR alert set with a 100 threshold. I know it is supposed to alert you when your HR is above 100 BPM after inactivity, but it should have never spiked, as my HR is usually in the 130's after a warmup before I start my run and never goes above 180-190 during my runs, so there's no way it should have went off. Has anyone else experienced this?
So after reading that the sensors draw more power during an activity, I decided to set it on a run while I'm sitting still. The sensor went off 3 times in 2 minutes and then stopped. I discarded the run and turned it back on again. Again it went off another 3 times with "Heart Rate 255". The whole time I was checking my pulse and it never went above 80. Starting to think my watch is defective.
