Does switch's Utilization Category AC-15 include a desktop?

In summary, Dave is trying to find a limit switch to control the power to a desktop PC. He is looking for a switch with an AC-15 rating, which would include a desktop PC. However, he is not sure if relays would be a good option because the switch would form the mains isolation switch. He has two plans, one of which is to use a rotary switch and the other is to use a toggle switch isolator. He is also considering using a microwave oven's door interlock switch.
  • #1
Paul Uszak
84
7
For reasons beyond understanding, I'm trying to source an industrial limit switch to control the power to a desktop PC. It's run on a switch mode standard computer PSU.

Most of the limit switches I've looked at are rated 5 amps @ 220 VAC. But they also have an AC-15 rating usually much, much lower, perhaps as low as 0.2 amps. I think that AC-15 applies to electromagnetic loads. Does this include PCs? They don't have much in the way of transformers...

Otherwise, how can I use a limit switch for controlling my PC?
 
Last edited:
Engineering news on Phys.org
  • #2
Limit Switch ??

limit switches are used for controlling a motor and other mechanical items connected to it

you have better more clearly explain your use of the term Limit Switch

Dave
 
  • #3
Something like (but not limited to) one of these:-
limit-switch.jpg
 
  • #4
Relays are used for higher power applications of limit switches.
Why you'd use one for a computer boggles the mind..
 
  • Like
Likes davenn
  • #5
billy_joule said:
power applications of limit switches

The nub of the question. Does power category AC-15 include a desktop PC?
 
  • #6
I have to rule out relays as this switch will form the mains isolation switch, so there's no power to drive a solenoid... :frown:
 
  • #7
some guidancehttp://www.nkkswitches.com/pdf/electricalratings.pdf

Inductive load stresses the contact on opening. The arc is difficult to extinguish.
Capacitive load stresses the contact on closing. Huge inrush current flows while the contact is still bouncing..
Paul Uszak said:
They don't have much in the way of transformers...
The SMPS has huge capacitors. Some limit inrush current , some don't.

Do you hear a "pop" when you plug it into an outlet ? Do touch-lamps switch off ? That's symptoms of big inrush.
 
  • Like
Likes Paul Uszak
  • #8
What exactly are you trying to accomplish here? We might have some alternate suggestions for you to try if we knew why you needed to isolate the power.

BoB
 
  • #9
jim hardy said:

Thanks Jim, just read this. Looks like I'd be better off using a relay somewhere. This means I'll have to rethink my isolation layout.

Thought: Why then do domestic socket switches not have usage categories? In the UK, they're all rated 13 amps. Doesn't matter if you're switching a welding machine, most powerful vacuum cleaner in the world or fairy lights.
 
Last edited:
  • #10
I'm building a pc in the Steampunk style. It will have a large lever on the side to turn it on, based on :-

indexd.jpg


There will be two power supplies and other mains equipment inside the computer case, so I'd like an isolation switch upstream of all of this. It would be really cool if the lever switch actually worked for real as the isolator. Just like in those mad scientist films. The limit switch would be the switch operated by the lever's shaft. As it's the isolator, there's no other power available for relays, mosfets etc.

My plan B is to connect the lever at it's fulcrum to an industrial 16 or 20 amp rotary switch such as:-

images?q=tbn:ANd9GcRxPhUTVGTu4L-p6pq5vaTB1MctYZ5xvsWw0APJv20FxcKbifHb.jpg


If I can't reliably attach the lever to this switch, I'll have to fall back to plan C and go with a normal toggle switch isolator,, and a relay /limit switch combo to get the lever operational somewhat. This is the least preferred option.
 
  • #11
They do make relays that are mains voltage rated coils. You could drive one of those with the limit switch or a microswitch which are generally much cheaper.
http://download.siliconexpert.com/pdfs/2012/2/4/13/2/21/73/hnw_/manual/v7-2b17d8-207.pdf

Then you don't need any extra voltages.

The microswitch type snap action switches come in many different lever styles.

Another option is to arrange for your steampunk lever to flip a standard light switch internally.

BoB
 
  • #12
rbelli1 said:
Another option is to arrange for your steampunk lever to flip a standard light switch internally.
not a bad idea. Cheap and easily replaced.

Microwave ovens have an interesting switch in their door interlock system. Usually it's the middle one.
Two of the microswitches close when the door is closed. They allow current to the relay that powers the big magnetron.

A third switch, usually a different color, closes whenever the door is NOT fully closed.
That one is connected directly across power to the magnetron supply.
That's so that should the other two switches somehow let the magnetron get power with door not fully closed,
maybe because the door is warped or a relay has stuck shut and somebody opens the door, ,
it'll blow the power fuse to protect the folks nearby. .
So that different switch is built to take a large gulp of current.

Doubtless you'll scrounge around junkpiles for switches.
If you pillage a microwave oven door switch be sure to get that fuse-blowing one, not one of the little guys for they only switch relays ..
The numbers on the switch should lead you to its ratings
http://sensing.honeywell.com/honeywell-sensing-micro-switch-v7-basic-product-sheet-004987-1-en.pdf

I like steam and understand completely. . Good luck. Be careful
 
Last edited:

FAQ: Does switch's Utilization Category AC-15 include a desktop?

1. What is Utilization Category AC-15?

Utilization Category AC-15 is a standardized rating system used to determine the application and capability of electrical switches in different operating conditions. It describes the type of load (AC or DC), the current rating, and the switching frequency that a switch can handle.

2. Does AC-15 include desktop usage?

No, AC-15 does not specifically include or exclude desktop usage. It is a rating system that applies to all types of switches, including those used in desktop applications. The rating is based on the switch's ability to handle the specified current and switching frequency, regardless of the application.

3. What is the difference between AC-15 and other Utilization Categories?

Each Utilization Category is designed for a specific type of electrical load and application. AC-15 is primarily used for switches that control circuits with moderate inductive loads, such as solenoids and contactors. It differs from other categories in terms of the current and switching frequency ratings.

4. How is AC-15 calculated for a switch?

The AC-15 rating is calculated based on the switch's ability to handle a specific current and switching frequency. This is typically determined by testing the switch under controlled conditions and measuring its performance. The rating is then assigned according to the standardized categories set by organizations such as UL and IEC.

5. Can a switch with AC-15 rating be used in other applications?

Yes, a switch with an AC-15 rating can be used in various applications as long as the current and switching frequency requirements are within the rating's specifications. However, it is always recommended to consult with the manufacturer or an expert to ensure the switch is suitable for the specific application.

Back
Top