My wife’s Swizzix machine’s On/Off lighted push button switch has failed. I have the failed switch out of the machine and this info I gathered from it. LA160-12A, 250v 3A, and written lightly on the body of the switch is 24v which I’m guessing is the voltage to energize the light. I believe the mfr is Switech in China. Can you help me find a cross @ DK?
Thank you for contacting DigiKey , from what I am finding with the info you gave take a look at the link below and see if any of these will work for you . Part number 108-PLP16-24SQ6-SE4-ND
Thanks Craig
Thank you for this info, Craig. I’m ordering qty 2 - an extra one in case I blow up the first. Two questions as I look at the contact arrangement for SPDT illuminated in the PLP16 spec. 1. For powering the LED, will I blow it if I get the power and ground backwards? or, will it just not come on? 2. In the contact arrangement illustration, I see pins 1 and 3 are for switching power on. Pin 2: is this a ground? I’m not sure In understand what the line/circle leading from that means. Or, does this indicate it is not used?
To quote the old National Enquirer at the grocery checkout: Inquiring minds want to know!
Thanks, bill
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Hi billmfifty,
To answer your questions:
Answer:
According to the schematic shown on page 3 of the datasheet, there are two LEDs installed back-to-back, which means that it can handle AC or DC voltage, and you can connect it either way for DC without a problem, despite the fact that there is a “+” and “-” indication on the plastic next to the two contacts.
Answer:
The line and circles in the schematic are internal switch arm and contact points. The pins can be wired multiple ways, depending on your specific needs.
This is a “single pole, double throw” (SPDT) switch, which has three contacts - a common contact (pin 1), referred to as a “Pole” and two “Throws”, which are the two positions the switch arm will pivot between, depending on the position of the button actuator. These are labeled on the switch as “C” for the common contact, “NC” for the normally closed contact, and “NO” for the normally open contact.
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The common contact “C” is always connected to the pivoting internal arm mechanism.
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The normally closed contact “NC” is connected to the pole when the switch is in its initial unactuated state, and opened when the switch is actuated.
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The normally open contact “NO” is open when the switch is in its unactuated state, and closed when the switch is actuated.
If you intend to use this switch to turn on a device, you would typically wire power to the common pin (pin 1, labeled “C” on the switch body) and then connect your load to the normally open pin (pin 2, labeled “NO” on the switch body).
Howdy, David. I finally found time to install the switch I purchased a couple weeks ago. I’m betting I got something backwards. I identified the wires attached to the old, failed switch, +, -, NO, C. I though I had installed them properly on the new switch, but when I add power, the switch never turns off. The only way for the system to go inoperable is for me to unplug the power. Does this sound to you that I got the NO and C wires backwards?
Another possible clue: the LED in the switch goes on when I apply power, and doesn’t go off even when I return the push button to the off position. Is the LED supposed to stay on as long as there is power, or is it supposed to go off when the switch is off?
I’ve been sourcing and costing in this industry for 30 years, but have little experience actually doing anything inside a box, so your help is very appreciated. I’ve mentioned the help you have been to our DK rep, Melissa Rux, and will amplify my appreciation next time I speak to her.
Regards, bm
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Hi billmfifty,
I’m not quite sure what the issue is right now.
A couple of questions:
- Do the switches physically look the same?
- On your original switch, was it a “momentary” or “alternating action” type? A momentary switch will return to the initial state via the internal spring mechanism as soon as released. An alternating action type like the one you ordered (PLP16-24SQ6-SE4) will remain in the pushed state until pushed again to return to the original state.
What I don’t know at this point is how your product’s power function actually works. Some devices use the power switch to directly pass or interrupt the current flow to the rest of the system. An alternating action switch would be used for this type.
Other devices use the power switch just as a momentary signal to tell some smart part inside the “standby section” to power up the rest of the system. This product design architecture will always provide power to the standby section of the internal system, and will use a momentary type switch to send the signal to power up or down the main system.
Based on what your describing, you may have the latter type.
The switches don’t look much alike because I’m replacing a faulty one made in China and the mfr of my wife’s machine refuses to tell me anything about it. The p/n I purchased is PLP16-24-SQ-6SE4. I found the location designations on the old switch, +, -, C and NO and thought I had terminated the wires going to the old switch to the same designations on the new switch. The board receives 24v from an external power supply and sends it via two red wires to the switch, + and -. The other to wires, black, go to NO and C.
As I recall from looking at the machine before it went south, it would idle with power on, but the press motor not running, when the on/off switch was ON. If I turned pushed that switch to turn it off, the light in the switch would go dark and the system would shut off. Now, however, the system stays live and ready to go regardless of whether or not the new switch is depressed for ON, or released for OFF.
It’s still hard to tell from your description which type of switch was used originally. When you pushed the switch button, did it pop back up to full height when released, or did it only come up part way?
An alternating action type would typically only come part way up when released, whereas a momentary type would return to full height each time after being pressed.
I think I figured it out, while fixing my wife’s breakfast. I believe I mixed up the two, 2-pin, JST plugs and put the incoming power on the header going directly to the switch. That could explain why it never turns off…(right…?..maybe?..)
Possibly. Hopefully. I’m afraid it’s hard to diagnose without seeing it and being able to check voltages, test circuit paths, etc.
I swapped the two 2-Pin JSTs’ locations and got nothing. Then I decided to check the switch, itself, and shazam!..it was bad. In both the button depressed and button released positions my beeper kept going. So it was a bad switch all along. Fortunately, I have so little faith in my ability to get things right that I purchased two of the switches. The 2nd one works fine and my wife now has her press back and I can, FINALLY, return to the salt mine that is sourcing and quoting RFQ’s.
Thank you for your feedback. It kept me thinking about the next place to look.
Ciao,
bill
Congratulations!
It’s always great when an appliance can be kept in service.
I’d guess the mistaken wiring on the first switch put current limited power directly across the contacts burning its contacts closed.
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