One of the arguments I’ve seen is about whether people should really trust the electronics. For better or worse, that ship has already sailed. We already know that we put our lives on the line every time we hop in a car. Although our safety is largely dependent on our own actions as drivers and the actions of other people, modern safety systems such as anti-lock brakes and electronic stability control improve your chances of avoiding or surviving an accident. In the ideal situation, you’ll have multiple safety systems in place, and each of those will be redundant. For example, the safety-critical systems on commercial airplanes are triple-redundant. If the plane needs a sensor to do something, it actually has three. The downside is that all the redundancy comes at an enormous cost, so by the time you get down to the level of consumer products, you’re lucky to have any safety system. You still need to practice some care in order for the safety system to do any good. In the worst-case scenario, if the safety system fails, you’re probably no worse off than you were without it in the first place.
So what about when it does fail? After all, it’s not uncommon for electronics to just fizzle out. If the capacitors on my computer’s motherboard start leaking after a few years of service, what’s to stop the same thing from happening in a table saw’s electronic braking system? Fortunately, the SawStop safety system runs diagnostics every time you power on the saw. You would expect with so much on the line, these diagnostics should be very thorough, and that the parts of the system most likely to fail would be easily replaceable. But that still leaves so many open questions. Is there a certain useful life for a SawStop saw and/or brake cartridge? And if so, is it possible that SawStop might program their cartridges so you have to replace them every few years, even if the safety system has not been triggered? One Friday afternoon, I decided to ask SawStop:
Hi, I’m planning to buy a SawStop PCS this spring but have a few questions.
1. I know a lot of electronics deteriorate over time, and other safety devices such as smoke detectors and CO detectors need to be replaced every
5-10 years. If the brake is never triggered, how frequently will I need to replace the brake cartridge (or some other part of the braking system) just because it’s old?
2. Is it based on number of hours the safety device is enabled, or a more general guideline such as every 5 years?
3. From the FAQ on your website I understand that the saw will run diagnostics on startup and will indicate whether the system is working correctly or not. If the brake cartridges have a recommended service life, is this artificially enforced? For example, if the service life is 1000 hours, does the brake effectively report to the saw that it no longer works after 1000 hours, or does it continue to work fine until the electronics are actually somehow compromised?
4. I’ve read that newer revisions of the saws get improved flesh-sensing technology. Do you only get this if you buy a new saw, or are these “upgrades” included in the brake cartridges themselves?
On the following Monday, I received this reply:
Thank you for contacting SawStop. In response to your request, there is no specific life span or recommended shelf life of our cartridges at this time. As you noted, the saw does a self check and should anything be wrong, the saw will exhibit a pattern of lights to make this known. We program the cartridges with the most up to date software as they ship, so it is not dependent on the saw. Thanks!
Don’t wait for an accident, buy SawStop today
Sales Support Specialist
Although the response is somewhat generic, it does suggest that most of the electronics for the safety system are housed in the replaceable brake cartridge itself, and that the saw may only have the minimal amount of electronics to display the results of the power-on diagnostics. If you still don’t trust the diagnostics and want to be really proactive, or if you just want the most up-to-date programming in your saw, I suppose you could just get into the habit of replacing your brake cartridge every 3-5 years. But the important thing to remember is that you are the primary safety system, and the saw’s electronic safety system is just a backup.
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