Questions tagged [poe]
Power over Ethernet, a set of IEEE standards for transmitting electrical power along with data through an Ethernet cable.
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PoE power extractions using RT9400
I want to get power using RT9400. The thing is I have schematics for RT9400 connections diagram in which they used magnetic transformer.
My question is can I directly use RT9400 with PoE connector to ...
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Telecom Lines Conducted emissions noise travel
I am seeking an explanation of how conducted emissions on telecom lines are measured.
The frequencies of interest are at 150kHz to roughly 850kHz.
The size of the unit is 30cm by 30cm by 15cm. The ...
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Is there a way to non-destructively test whether an Ethernet cable is pure copper or copper-clad aluminum (CCA)?
I got an Ethernet cable on Amazon for what was, in hindsight, a suspiciously good price. The description says it's copper but one of the one-star reviews claims it's actually copper-clad aluminum (CCA)...
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Telecom Lines Conducted emissions [closed]
We have rented a Telecom line ISN to conduct some in-house pre-compliance testing. The test setup closely follows the CISPR32 standard. We encountered issues with conducted emissions in the lab, which ...
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ESD knocking out PHY on device with unisolated POE
I inherited this design, one problem I am having is ESD on the chassis knocks out the PHY, sometimes it can't even be reset via software. I am curious if anyone can spot any glaring errors with the ...
- 84.8k
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Is this heat from the PoE module normal?
I have added the Silvertel Ag9205S 5 V PoE module to my design in order to provide 5 V power to the system using Ethernet. I also have USB power that can provide 5 V as well. I have a diode on the USB'...
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Conducted Emissions from a PoE powered equipment according to En55032/CISPR32
I'm seeking clarification on Conducted Emissions measurements for a PoE powered device. I've reviewed both the CISPR32 and CISPR 16-2-3 standards, yet I couldn't find specific guidance on the setup ...
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Power over Ethernet (PoE) power supply requirements clarification, PSE < PD?
IEEE 802.3at-2009 Table 33-7 shows minimum power supply (PSE) levels that seem to be less than the peak power that the powered device (PD) could draw for Class 1 and 2. Can anyone clarify how these ...
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Is using the shield in a CAT cable for return current a bad idea?
Consider a PoE solution that uses shielded CAT cables and where the shield is connected to signal ground on both the PSE and the PD side. In this case, the shield is most probably presenting a lower ...
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Selecting Optoisolator CTR for MPS MP8009 SSR Forward Topology
Do the optoisolator Current Transfer Ratio (CTR) Min and Max matter for this design, and if so, what is the benefit of selecting each ratio?
Here is the MPS MP8009-GV PoE controller datasheet, inside ...
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Raspberry Pi 4B POE Rectifier Circuit recommendation
Am I doing the signal rectification properly for the POE application using the Diodes on the RPI 4B 4 pin header?
I have attached images of my design, as I am trying to use a Raspberry PI 4B with POE (...
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Signal Ground near Earth POE
I have Earth Ground 48V poured around the components before our diode array. I have three seperate ground planes, one for Earth, one for our POE components before the transformer, and our signal 5V ...
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Transformer Schematic Explanation
Why does this design use two winding secondary outputs? I do not understand what is happening here. I know that the device converts for POE 5V 4.8W, but that secondary winding setup, how could I ...
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Help troubleshooting a PoE circuit
After much ado I've designed a simple PoE addon board for a custom ESP32. However, when plugged in, the PoE light on the switch goes on for about half a second, and then goes back off. Seems like its ...
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Conducted emissions testing for POE 802.3 device?
For IoT devices with a Powered Device (PD) for Power Over Ethernet (POE) and not plugged into AC mains; What, if any, standards would a device potentially be subject to at an Nationally Recognized ...
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