Electrical engineers...what is this?

11thHour

Senior member
Feb 20, 2004
796
1
0
Below is a housing that contains a 12v 'massage' vibration motor from an office chair. The red wire leads connect to the two terminals on the motor, and these terminals are bridged by a yellow wire with an orange clamshell piece soldered in the middle of it.

GoefMQB.jpg


What is the orange piece bridging the terminals, and what does it benefit? I am replacing the motor inside the housing and am wondering if I should use one of these for the new motor (and if so, how would I go about getting one rated appropriately?)
 

Matthiasa

Diamond Member
May 4, 2009
5,755
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If you are just replacing the motor you should be able to reuse it. As stated it appears to be a capacitor and it is likely being used smooth out the voltage being input in the motor.
 

z1ggy

Lifer
May 17, 2008
10,010
66
91
Thanks. Indeed, underneath, I found:

.1
25v
AEC

?

.1 probably refers to the capacitance, but I find it weird there's no unit. But if it's pretty small, it's safe to assume that its prob not .1F... It's probably .1 microfarad

AEC could = Alternating Electric Current.. but.. meh that seems like a weird thing label on a capacitor.
 

VashHT

Diamond Member
Feb 1, 2007
3,355
1,435
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I'd be surprised if the new motor didn't come with it on there already, I would definitely use it though. Like people said it's probably a filter cap, but it may be used to filter noise from the motor getting back onto the line rather than the other way around. I'd say it's definitely .1uF, .1F would be huge and it's usually labeled as pF if it's that small. if you have a good DMM you can measure it when you take if off the motor, don't measure it in circuit as that won't give you an accurate reading.
 

11thHour

Senior member
Feb 20, 2004
796
1
0
If you are just replacing the motor you should be able to reuse it. As stated it appears to be a capacitor and it is likely being used smooth out the voltage being input in the motor.

Great to know. Thanks everyone for the feedback.
 

Jeff7

Lifer
Jan 4, 2001
41,596
20
81
I'd be surprised if the new motor didn't come with it on there already, I would definitely use it though. Like people said it's probably a filter cap, but it may be used to filter noise from the motor getting back onto the line rather than the other way around. I'd say it's definitely .1uF, .1F would be huge and it's usually labeled as pF if it's that small. if you have a good DMM you can measure it when you take if off the motor, don't measure it in circuit as that won't give you an accurate reading.
A bunch of 0.1F ceramic capacitors in parallel could be fun to play with though.:D
I'd hate to think how much it'd cost to get a ceramic cap with that much capacitance though.:eek: Or how big it would be. Digikey has stock of some 470uF 4V caps. $2 each if you buy two full 500pc reels.
 
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werepossum

Elite Member
Jul 10, 2006
29,873
463
126
.1 probably refers to the capacitance, but I find it weird there's no unit. But if it's pretty small, it's safe to assume that its prob not .1F... It's probably .1 microfarad

AEC could = Alternating Electric Current.. but.. meh that seems like a weird thing label on a capacitor.
AEC designates Aritec Electronics CO., a popular manufacturer of capacitors. (Oops, LTC8K6 beat me to it.) And there is no unit designated because all consumer capacitors are rated in microfarads. Or at least, as far as I know; I've never seen one designated in any other unit, from several hundred to one thousandth of a microfarad.

There are three common uses for capacitors in motor circuits - filters, starting torque, and running torque. From the size relative to the motor I'm assuming that those people saying filter are correct; start or run capacitors in my experience are a LOT bigger and are potted. I'm also guessing it is a ceramic disc capacitor by the rating and shape. Personally I'd probably replace it, as ceramic disc capacitors are relatively cheap, aren't all that robust or long-lived, and as filters typically work in conjunction with a specifically sized inductor as a simple LC circuit. (Although maybe the motor wiring is the inductance, I dunno.)
 

Rubycon

Madame President
Aug 10, 2005
17,768
485
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.1 would be picofarads for sure on a ceramic.
.1 microfarad is more in the polyester/tantalum range depending on volts.
Larger caps used for start/run windings on induction motors are electrolytic.

That cap could be part of a filter for regulatory compliance.

More interesting, a vibrator for a chair? Doesn't look like it would be a hawaii chair so what is it?

Oh for reference: https://www.youtube.com/watch?v=E9_amg-Aos4
 

Jeff7

Lifer
Jan 4, 2001
41,596
20
81
.1 would be picofarads for sure on a ceramic.
.1 microfarad is more in the polyester/tantalum range depending on volts.
Larger caps used for start/run windings on induction motors are electrolytic.

That cap could be part of a filter for regulatory compliance.

More interesting, a vibrator for a chair? Doesn't look like it would be a hawaii chair so what is it?

Oh for reference: https://www.youtube.com/watch?v=E9_amg-Aos4
Oh god not that commercial. :eek:
The people on the chairs, behind the smiles: "This is it. This is my life now. It's over. I'll never know dignity again."
 
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freeskier93

Senior member
Apr 17, 2015
487
19
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.1 would be picofarads for sure on a ceramic.
.1 microfarad is more in the polyester/tantalum range depending on volts.
Larger caps used for start/run windings on induction motors are electrolytic.

That cap could be part of a filter for regulatory compliance.

More interesting, a vibrator for a chair? Doesn't look like it would be a hawaii chair so what is it?

Oh for reference: https://www.youtube.com/watch?v=E9_amg-Aos4

Not sure where you came up with that, 0.1uF is an extremely common value for ceramic caps. I'm using a whole bunch of 0.1 uF ceramic caps for decoupling the Vdd lines on PIC microcontrollers, as required from the datasheet.

0.1 uF ceramics are pretty much the defacto value for decoupling.

Also, 0.1 puff is incredibly small... It would be totally useless in this application because it would only be able to filter extremely high frequencies.
 
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Rubycon

Madame President
Aug 10, 2005
17,768
485
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Not sure where you came up with that, 0.1uF is an extremely common value for ceramic caps. I'm using a whole bunch of 0.1 uF ceramic caps for decoupling the Vdd lines on PIC microcontrollers, as required from the datasheet.

0.1 uF ceramics are pretty much the defacto value for decoupling.

Also, 0.1 puff is incredibly small... It would be totally useless in this application because it would only be able to filter extremely high frequencies.

:oops:

This is practically a necro, but yes you are correct. I was a bit distracted at the vibrator concept and was thinking of the higher voltage Spragues used in EACs.