led on when it should be off.

Thread Starter

Bappi

Joined Oct 19, 2023
7
  1. ok anyone here with some knowledge of switches as im getting an odd thing happening.

    I built a 3d printer and wired it up according to the manual and everything works as intended but due to my disability wanted a power switch at the front of the machine to power on and off instead of reaching around to the back as its against a wall.
    I bought a 240v 5amp current Push Button Switch with led. I have wired it as per the first diagram mode 1. the 2nd pic shows the 5 pins.

  2. Screenshot 2023-10-19 210013.jpgScreenshot 2023-10-19 210516.jpg
    I have taken the Live and negative from the rear switch to the front so when power at the back is on its still off until I turn it on at the front. I have wired the switch as per the diagram but when the printer is switched off at the front with power on at the rear the switch led is a dim glow. When I press the button to turn the power on its bright and everything powers up as intended.
    ScreenShot_20231019015005.png

    fig 3


This is currently how its wired up from the kettle plug it goes to the rear switch with 4 wires 2 in 2 out, I have taken the 2 from the on side of the switch to the front of the printer. this is then wired as per fig3

when i turn rear switch on the front led glows dim but when i push the switch on all the internal electronics light up as intended.
 

DC_Kid

Joined Feb 25, 2008
1,072
You have a bridge rectifier on 240vac?
Is the light an actual LED?
When you power off this new setup, using a volt meter, is there voltage on the Wago wires?

I not sure why you would feed the Common terminal, because when the switch goes "off" to NC then you place voltage on a terminal you do not intend to use. If NO is all you need, then move your feed voltage to NO and move the LED+ wires over to Common.
 

Thread Starter

Bappi

Joined Oct 19, 2023
7
You have a bridge rectifier on 240vac?
Is the light an actual LED?
When you power off this new setup, using a volt meter, is there voltage on the Wago wires?

I not sure why you would feed the Common terminal, because when the switch goes "off" to NC then you place voltage on a terminal you do not intend to use. If NO is all you need, then move your feed voltage to NO and move the LED+ wires over to Common.
https://www.aliexpress.com/item/100....order_list.order_list_main.24.34de1802mFfIpV this is the switch I have its 110 - 240v, with 5v current for led. It does say the light is an led but I wouldnt know for sure without taking it apart. As yet vi havent tested with a metre but i did disconnect the wagos to the internal electrics and led was still showing a glow. the sole purpose for adding this switch was to make my life easier with an indicator power was on. Common im guessing is the middle pin ?

No idea about a bridge rectifier whatever that is
 

DC_Kid

Joined Feb 25, 2008
1,072
It is rather easy o accidentally put the power-on indicator across the contacts instead of between the switched side and the neutral.
The diagram shows what looks like AC to bridge recitifier. I could be wrong, maybe the "-" means Neutral and the "+" means mains hot ?
It also shows a 3-prong plug but only two 2 wires connecting. Is that L1-L2 (240) or a (L1-N) (120) connection?

I suspect it's a DC rated switch, but specs don't say.

My guess is, when switch is in NO position there's some leakage voltage making it to the NC pin (LED current) leakage. Only way to know is to measure the volts. If it's really AC, then the LED staying dim when the switch is off is likely some LED bias (leakage), which the ckt could be completed through the device connected to the Wago connectors.

As for LED, not really sure how they have the LED wired inside. I assume they handle LED current based on switch voltage rating, so with a 110-240v rating would it be more bright if the switch was on 240v vs 110v?
 
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Alec_t

Joined Sep 17, 2013
14,218
when i turn rear switch on the front led glows dim but when i push the switch on all the internal electronics light up as intended.
I guess the dim glow is because of slight leakage current between the common (C) and normally off (NO) contacts of the switch. Bright glow when you close the front switch would suggest you have the wiring correct.
 
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DC_Kid

Joined Feb 25, 2008
1,072
I guess the dim glow is because of slight leakage current between the common (C) and normally off (NO) contacts of the switch. Bright glow when you close the front switch would suggest you have the wiring correct.
It might go away by not using C connection as the feed, like I mentioned earlier.

electrons can still move without wire.

 

djsfantasi

Joined Apr 11, 2010
9,151
The diagram shows what looks like AC to bridge recitifier. I could be wrong, maybe the "-" means Neutral and the "+" means mains hot ?
Usually the + and - terminals of a bridge rectifier are the DC output. The AC input, hot and neutral, are indicated with ~ (tilde).

Does that make sense to you?
 

Thread Starter

Bappi

Joined Oct 19, 2023
7
+ and - are my way of putting positive and negative live and common i guess i should have put ? So would it still be safe to use with the dim glow being there or does it need something else like maybe a diode or such like. Bridge rectifier ive no idea what that is all thats connected that side is the plug socket, the switch with 13amp fuse and then the new switch im adding to the front. It then goes off to a 5 block wago which supplies a raspberry pi, 2 power packs 24v an octopus 1.1 motherboard a u2c board an rs200 think thats it. You can see the wago bank on the right hand side. IMG_20230616_222343.jpg
 
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Thread Starter

Bappi

Joined Oct 19, 2023
7
I have just checked the manual and its a Filtered Mains Inlet that i put the plus and minus on the square block right at the back by the opening and next to that is the switch.1697830390592.png
 

MisterBill2

Joined Jan 23, 2018
17,794
I have a suggestion that should reduce confusion a bit. DO NOT USE + and - for identities of AC wires. L and N, standing for Line and Neutral will avoid much confusion. Even HOT and Ground will be a bit less confusion, and can be understood rather well.
Consider that if the switch is wired correctly, and the indicator is wired correctly, then the indicator is in parallel with the imput of what looks like a fair sized switching mode power supply. The mains input to that supply should be a much lower resistance than any possible leakage resistance of a switch.So it does not seem reasonable to think it is switch leakage current lighting the indicator.
Does the TS have access to a meter capable of measuring resistance? I suggest measuring the resistance of the indicator, because I doubt that it is an LED. I suspect it is a neon indicator that will indicate an open circuit when an ohm meter check is made..
 

LesJones

Joined Jan 8, 2017
4,172
Are we sure that the item that has been called a bridge rectifier is not a solid state relay ?
Can you post the wiring diagram that shows you how to connect all the parts together ?
I would expect this to be in the manual that you mention in your first post.

Les.
 

tonyStewart

Joined May 8, 2012
127
when i turn rear switch on the front led glows dim.
This is due to E-field coupling of line voltage to the LED by stray capacitance and closeness of wires or due to unknown leakage if the rear switch controls a Triac or SSR.

Assuming the LED is drawing 1 mA dim at 1.5V, this is equivalent to 1.5 kOhm.

You can suppress this with either a Cap or a resistor across. I would use a cap across the LED. A small ceramic axial or radial part should work. 0.1uF is pretty common and is equivalent to about 3 kohm at line freq. That should be enough to drop the voltage 50% and be below the LED threshold.

If the rear switch controls a Triac, the leakage will be conducted and could be much more than radiated. This may require both a resistor and a bigger Cap.
 
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Thread Starter

Bappi

Joined Oct 19, 2023
7
Just looked at the bom and found the link to the power inlet so heres the data sheet on that part.
I have also found specs for the same push button switch altho not exactly the same design as the lit part has a different pattern on it.
Specifications:
Thread depth: 5/8 (16mm)
Head diameter: 3/4" ( 18mm )
Button diameter: 0.36" ( 9mm )
Mounting hole size: 5/8" ( 16mm )
Depth inc contacts: 1.3" ( 35mm )
Switch combination: 1NO1NC
Operation types: Latching
Switch rating: 5A/250VAC, 5A/30VDC
LED rating: 15mA, AC/DC 12V
LED color : Blue
Head shape : High flush
Enclosure material : Aluminium alloy
Protection level: IP67,IK10

"I have a suggestion that should reduce confusion a bit. DO NOT USE + and - for identities of AC wires. L and N, standing for Line and Neutral will avoid much confusion. Even HOT and Ground will be a bit less confusion, and can be understood rather well."
on the manual it has the plus and minus signs which is why they were used. Sorry for the confusion. (im not an electrician)
I do have a multi metre but wasnt sure if testing ac was a good idea.
 

DC_Kid

Joined Feb 25, 2008
1,072
Usually the + and - terminals of a bridge rectifier are the DC output. The AC input, hot and neutral, are indicated with ~ (tilde).

Does that make sense to you?
I know how bridges are marked. It's just not clear what that block is in initial post. Is it a junction block? Is it SSR?

Are we sure that the item that has been called a bridge rectifier is not a solid state relay ?
Post #10 sure looks like an SSR. Just not clear to me how this new switch is wired in. The diagram posted early on just shows Wago connectors,a plug, and a switch. Not very common to drive a SSR gate side with 240ac. Also in that same pic, one screw of the "SSR" is not even connected to a wire?

****************
Even with the leakage, try swapping the wires of NO and C. That may change the coupling in the switch, enough so to eliminate leakage current.
 

k1ng 1337

Joined Sep 11, 2020
910
Just looked at the bom and found the link to the power inlet so heres the data sheet on that part.
I have also found specs for the same push button switch altho not exactly the same design as the lit part has a different pattern on it.
Specifications:
Thread depth: 5/8 (16mm)
Head diameter: 3/4" ( 18mm )
Button diameter: 0.36" ( 9mm )
Mounting hole size: 5/8" ( 16mm )
Depth inc contacts: 1.3" ( 35mm )
Switch combination: 1NO1NC
Operation types: Latching
Switch rating: 5A/250VAC, 5A/30VDC
LED rating: 15mA, AC/DC 12V
LED color : Blue
Head shape : High flush
Enclosure material : Aluminium alloy
Protection level: IP67,IK10

"I have a suggestion that should reduce confusion a bit. DO NOT USE + and - for identities of AC wires. L and N, standing for Line and Neutral will avoid much confusion. Even HOT and Ground will be a bi
A t less confusion, and can be understood rather well."
on the manual it has the plus and minus signs which is why they were used. Sorry for the confusion. (im not an electrician)
I do have a multi metre but wasnt sure if testing ac was a good idea.
Just looked at the bom and found the link to the power inlet so heres the data sheet on that part.
I have also found specs for the same push button switch altho not exactly the same design as the lit part has a different pattern on it.
Specifications:
Thread depth: 5/8 (16mm)
Head diameter: 3/4" ( 18mm )
Button diameter: 0.36" ( 9mm )
Mounting hole size: 5/8" ( 16mm )
Depth inc contacts: 1.3" ( 35mm )
Switch combination: 1NO1NC
Operation types: Latching
Switch rating: 5A/250VAC, 5A/30VDC
LED rating: 15mA, AC/DC 12V
LED color : Blue
Head shape : High flush
Enclosure material : Aluminium alloy
Protection level: IP67,IK10

"I have a suggestion that should reduce confusion a bit. DO NOT USE + and - for identities of AC wires. L and N, standing for Line and Neutral will avoid much confusion. Even HOT and Ground will be a bit less confusion, and can be understood rather well."
on the manual it has the plus and minus signs which is why they were used. Sorry for the confusion. (im not an electrician)
I do have a multi metre but wasnt sure if testing ac was a good idea.
A high quality multimeter will have its rating listed on the unit. To find which is Live or Neutral, put one probe into a known ground socket. There will be a mains high voltage between Live and Ground but not Neutral and Ground.

If there is a voltage greater than 10V on the Neutral wire to Ground wires, I think you have a coupling problem but having a voltage on Neutral to Ground doesn't necessarily mean a large current will flow. This is just a way to see if your system is behaving normally.
 

DC_Kid

Joined Feb 25, 2008
1,072
Ahh, that block in 1st post is a IEC-320 filtered panel power connector.

The power cord has a ground, and so does the connector. That ground should carry through to the chassis of the "machine".

From the shape of the outlet used in post #1, euro 230vac with "ground" pin? Euro 50Hz is L1-N-Gnd.
 
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eetech00

Joined Jun 8, 2013
3,820
Is there a small on-board battery anywhere?
The LED is still connected across the power supply input even when the switch is open. Maybe lit due to charged power supply filter caps? Does the LED remain dim or does it eventually go dark after time?
 

MisterBill2

Joined Jan 23, 2018
17,794
Based on the BOM, (Bill Of Materials), the illumination is a BLUE LED powered by 12 volts DC. Based on the circuits presented in post #1, the indicator is getting 240 volts AC applied across it. My conclusion is that the switch in the conversation is not the switch in the BOM.

And now we know, from post #10, it is actually an inline filter, mislabeld as a bridge rectifier. THIS is why we NEVER tag AC lines as + and -.
 

DC_Kid

Joined Feb 25, 2008
1,072
The BOM itself may be right on LED being a 12v LED, so maybe they insert an inline resistor and just let it run half-wave from the AC ?
 
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