Friday, September 9, 2011

Not user serviceable hell!! Or as Oldfool says: If you can't open it, you don't own it!

I have been lent a rather nice Polar CS200 heart rate monitor to aid in my training for the Desert Dash (thanks Jan)
Anyway, it turned out that the speed sensor was not working well, giving intermittent readings and getting distance and speed rather wrong. After some investigation I worked out that the sensor's battery was probably nearly flat, problem is the sensor is not "user serviceable". In other words you throw it away and pay through the nose for a new one. That's bullshit, particularly from a company like Polar.
A quick call to the agents confirmed this. Send it up to us and we'll replace the unit for $$$. Don't they get it? Downtime, the cost of sending the thing backwards and forwards across the country? I'm guessing that they simply use an RFID unit to scan the frequency of your old one, programme a new one and send the new one to you once you shelled out. Bin the old one when all that's wrong is a flat battery.

One of the most useful tools in my workshop is Google. In no time at all I found that these specific sensors are problematic and that you CAN open them and replace the batteries. Admittedly, one needs to use some delicate brute force and a Stanley knife, but voila and it's open. Replace battery (R15.00), increase tension of contact springs (i.e. bend them up a bit). Apply a small amount of Pratley epoxy to re-seal the unit and Josephine's your Uncle. Seal it properly.

That's it. Battery under the clip on the left. It's a CR 2035. The chest strap uses a CR2025, the CS200 unit  uses another CR2035.

The lesson? Just like the external BB bearings that say "Do Not Disassemble". Stuff 'em.

To be entirely fair to Polar, the rest of the CS200 is a dream. Easy to use, large display, downloads a treat. Even the mounting bracket is cleverly thought out.


  1. If you can't open it, you don't own it.

  2. Got some serious frustrations with my unit but no solutions forthcoming yet. Seeing one of the RASA guys works for them, I'm working my contacts but with holding final judgement.

    I like your approach - you had nothing to lose!

  3. The power of Google clearly illustrated. I was able to find out more about the product and it's problems than the SA agents were willing to acknowledge. It should be a core part of their product training to Google "Polar xyz problems" and then hear what people in the real world experience. Simply being able to regurgitate what is on the Polar website is not good enough. Now I get intermittent erratic heart rate readings (off the scale. Let's see what Google has to say....;)