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Comment by samwillis | Hacker News Reader

> you could hire a janitor's assistant to keep an eye out that the lights are off in the evening and turned on in the morning

This is ultimately the biggest failing, and what makes this so sad. For a fraction of the cost of this system you could employee someone and have this as part of their responsibility.

For automation to make sense, it can't just replace at the same cost (and certainly not cost more), it needs to be an order of magnitude saving. They may have done the math on this over say a 30 year period, but these systems never last that long.

I imaging the "half life" of a IOT system is about five years.

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Control systems often last decades, longer than most employees.

I've recently worked on a control system that is at least 30 years old. While you can't get the exact part any more - you can still get compatible replacements that drop in. There are still staff that are competent working with the platform.

They should be upgrading over the years, unless you think working with a MS-DOS computer would be advisable today.

Most education sectors use a large vendors control system with either vendor engineers, or local contractors.

Honestly, even today I would trust a system running MS-DOS far further than anything running Windows. The number of gas pumps I’ve seen blue screened and kiosks running Windows Update…

The only thing a more modern computer buys you is added complexity and more to go wrong. More RAM than your process needs? More to corrupt. What percentage of crud/resident processes on a “modern” is even related to the task we are assigning this machine? Less than 1%? It’s absurd. It’s like buying a Swiss Army knife with a million attachments to build a house. You can, but you shouldn’t.

> unless you think working with a MS-DOS computer would be advisable today

MS-DOS doesn't even have a networking stack by default, so it's air gapped out of the box. That in case you're worried about security.

Other than that, if you can control some relays from an esp32 with 4k ram, why wouldn't you be able to do it from an 8088 box with 64?

> Control systems often last decades, longer than most employees. ... > I've recently worked on a control system that is at least 30 years old.

I've met many people who are much more than 30 years old :) And I've worked in places where people retired only after ~40+ years. And replacements are relatively easy to find, depending on the nature of the work.

I think there is a reasonable debate to be had about what should be automated and what should be kept in human hands. I think we as a civilization need to sort out what the costs and opportunities are in light of the failure modes of both alternatives.

This was obviously not a good system design, but a box full of relays and PLC controller cost a whole lot less than the all-in employer cost of an extra employee.

They really should also be able to turn off the lights at the breakers unless they did something exceptionally stupid like put the fire control panels on the lighting breakers.

> but a box full of relays and PLC controller cost a whole lot less than the all-in employer cost of an extra employee.

Why would you need an extra employee just to turn on/off the lights? I think janitors or teachers always did that as part of the job before smart switches came around, no need to hire some "light manager".

Exactly: the person who checks the windows are shut, taps are closed, and locks the doors every evening can also switch the lights off.

BRB starting a smart cloud faucets for schools startup.

(Any teachers that want to use a toilet after 5pm will need a smartphone app installed.)

Having read most of the comments debating the pros and cons of the system this is an astonishingly simple solution! Sometimes I think those of us in technology look for problems to solve.

> you could employee someone and have this as part of their responsibility

Someone that calls in sick. Forms a union. Demands high wages for menial tasks. We need far fewer government employees.

Why not literally just ask the first one in and the last one out to handle the lights? This isn’t complicated. Someone locks the doors right? Can they not turn off the lights?

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