Galvanic USB isolator: verschil tussen versies

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(4 tussenliggende versies door een andere gebruiker niet weergegeven)
Regel 1: Regel 1:
[[Bestand:Usb-condom.jpg|150px|USB Galvanic Isolator/Separator]]
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[[Bestand:Usb-condom-av.jpg|150px|USB Galvanic Isolator/Separator]]
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[[Bestand:Usb-condom.jpg|miniatuur|USB Galvanic Isolator/Separator]]
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[[Bestand:Usb-condom-av.jpg|miniatuur|USB Galvanic Isolator/Separator]]
  
 
Most of our nodes are POE powered; but are not galvanically isolated from the LAN (power).
 
Most of our nodes are POE powered; but are not galvanically isolated from the LAN (power).
Regel 6: Regel 8:
 
It is common (to prevent rust) to run POE at negative voltages; so the 'plus' is somewhat near 0 Volt/earth; and the 'minus' is 40-60Volt below earth. But laptops and other USB devices tend to be wired the other way round.  
 
It is common (to prevent rust) to run POE at negative voltages; so the 'plus' is somewhat near 0 Volt/earth; and the 'minus' is 40-60Volt below earth. But laptops and other USB devices tend to be wired the other way round.  
  
So it is essential to use a [[Galvanic USB isolator|USB condom/galvenic separator]] when it is connected both to Ethernet and USB.  
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So it is essential to use a [[Galvanic USB isolator|USB condom/galvanic separator]] when it is connected both to Ethernet and USB.  
  
 
As otherwise there is a voltage delta of 48 or 2x72V between your devices and earth.
 
As otherwise there is a voltage delta of 48 or 2x72V between your devices and earth.
Regel 14: Regel 16:
 
They are relatively expensive; and as they are sometimes mandatory safety equipment when high (kilo) voltages are in use (220V is actually still [https://nl.wikipedia.org/wiki/Laagspanning classed as a low voltage]). These easily go vor 150 Euro's and more.  
 
They are relatively expensive; and as they are sometimes mandatory safety equipment when high (kilo) voltages are in use (220V is actually still [https://nl.wikipedia.org/wiki/Laagspanning classed as a low voltage]). These easily go vor 150 Euro's and more.  
  
However there is no need for that level of safety in our case; and as it happens - audiofiles worry about a similar issue; in their case the ground loops cause audio quality issues. So using these USB galvanic isolators (which can be had well under 15 euro) is a [https://www.amazon.nl/Huerous-Adum3160-Digital-Isolator-Digitale/dp/B0CLMBZTCG/ref=sr_1_5?__mk_nl_NL=%C3%85M%C3%85%C5%BD%C3%95%C3%91&crid=18RIQPEZYGYYF&keywords=usb+isolator+audio&qid=1704282532&sprefix=usb+isolator+audio%2Caps%2C76&sr=8-5 perfectly good solution].
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However there is no need for that level of safety in our case; and as it happens - audiophiles worry about a similar issue; in their case the ground loops cause audio quality issues. So using these USB galvanic isolators (which can be had well under 15 euro) is a [https://www.amazon.nl/Huerous-Adum3160-Digital-Isolator-Digitale/dp/B0CLMBZTCG/ref=sr_1_5?__mk_nl_NL=%C3%85M%C3%85%C5%BD%C3%95%C3%91&crid=18RIQPEZYGYYF&keywords=usb+isolator+audio&qid=1704282532&sprefix=usb+isolator+audio%2Caps%2C76&sr=8-5 perfectly good solution].

Huidige versie van 11 jan 2024 om 21:47


USB Galvanic Isolator/Separator
USB Galvanic Isolator/Separator

Most of our nodes are POE powered; but are not galvanically isolated from the LAN (power).

It is common (to prevent rust) to run POE at negative voltages; so the 'plus' is somewhat near 0 Volt/earth; and the 'minus' is 40-60Volt below earth. But laptops and other USB devices tend to be wired the other way round.

So it is essential to use a USB condom/galvanic separator when it is connected both to Ethernet and USB.

As otherwise there is a voltage delta of 48 or 2x72V between your devices and earth.

No need for expensive ones

They are relatively expensive; and as they are sometimes mandatory safety equipment when high (kilo) voltages are in use (220V is actually still classed as a low voltage). These easily go vor 150 Euro's and more.

However there is no need for that level of safety in our case; and as it happens - audiophiles worry about a similar issue; in their case the ground loops cause audio quality issues. So using these USB galvanic isolators (which can be had well under 15 euro) is a perfectly good solution.