12V DC wiring for 160 latching LED switches

Thread Starter

Onyx8789

Joined Apr 10, 2019
5
I am trying to figure out how I can wire 160 LED latching switches so they function normally (LED ON when switch ON) but once a year someone can press a master button and that will turn them all on (LED always ON). There are no devices to connect, we just want the latching button to light up when pressed (how it is currently wired) and then somehow incorporate a master button to turn them all on or switch their functionality to LED always ON. This is going on a wall of 160 buttons total so the connection needs to be replicated quite a few times. The attached PDF shows how we have it wired as of right now. Any help would be greatly appreciated!

Button is Ulincos U16F2
Switch Rating: 5A/250VAC, 5A/30VDC
LED Rating: 15mA/12VAC, 15mA/12V DC
 

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Thread Starter

Onyx8789

Joined Apr 10, 2019
5
You just need to run a 12V bus to all + pins, with a switch on that. so one daisy chained wire will do it.
So we tried that and what ends up happening is 1 button turns on all of them but we also need them to function individually. Connecting all the the + pins makes them function as a whole. We need to daisy chain them but also isolate the + connections from each other somehow.
 

Yaakov

Joined Jan 27, 2019
3,328
So we tried that and what ends up happening is 1 button turns on all of them but we also need them to function individually. Connecting all the the + pins makes them function as a whole. We need to daisy chain them but also isolate the + connections from each other somehow.
Then you will need logic, you can't just wire them to power.
 

AnalogKid

Joined Aug 1, 2013
9,290
Spidey beat me while I was feeding the dogs. The least complex method is to add isolation diodes. Note - there is not *any* method that does not involve rewiring all 160 switches in some way.

1. At each switch add a small signal diode (1N914, 1N4148, etc.) or small rectifier (1N400x) from + to the new lamp test bus. Cathode to +, anode to the bus. Depending on the answer to #3, each diode might carry that switch's load current.

2. Lamp test bus goes through the new switch to the 12 V source.

3. Critical question - when the new lamp test button is pressed, is it OK for power to go to all loads, including any of the individual switch loads that are *not* powered by their individual switches (loads with switches in the off position) at that time? If it is ok for all loads to come on during lamp test, skip #4.

4. At each switch, replace the wire between NO and + with a small signal diode (1N914, 1N4148, etc.) or small rectifier (1N400x). Anode to NO, cathode to +. This will decrease the LED voltage by 0.7 V.

ak
 
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