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#1 16-10-2009 14:36:34
- Visitor
- visitor
- Registered: 01-06-2007
- Posts: 37
H4531 - jumper function
Hello,
We have H4531. I observe that near the ethernet connector is a jumper.
What is the function of this jumper.
I ask that because I want to know if is possible to use it without POE receiver. We have a switch which is POE, but deliver the power on to the same wires with data. Also this switch you can manually select voltage(5-45V DC). H4531 has a voltage/data separator(filter) built in or the ethernet port will be damage if receive DC current on to the data wires?
Best regards.
Thank you.
Marin Constantin
Last edited by Visitor (18-10-2009 07:51:06)
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#2 19-10-2009 07:10:43
- HonzaD
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- Registered: 11-08-2008
- Posts: 294
Re: H4531 - jumper function
Hi,
We have H4531. I observe that near the ethernet connector is a jumper.
What is the function of this jumper.
Jumper near the Ethenret RJ45 is for a "hardware" factory default. Please see instruction manual (http://cometsystem.cz/english/manuals/i … xx-apx.pdf) on site 29.
I ask that because I want to know if is possible to use it without POE receiver. We have a switch which is POE, but deliver the power on to the same wires with data. Also this switch you can manually select voltage(5-45V DC).
No, for PoE support you MUST use PoE splitter (like a D-link DWLP50 - http://www.dlink.com/products/?sec=0&pid=368).
Your switch is probably IEEE802.3af compatible and automatically detect if connected device is PoE ready or not (switch not allow DC power supply if PoE is not supported).
IH4531 has a voltage/data separator(filter) built in or the ethernet port will be damage if receive DC current on to the data wires?
There is isolating transformer, but I think is not a good ideas connect directly DC power supply to the data line.
John
Last edited by HonzaD (19-10-2009 07:13:57)
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#3 19-10-2009 09:51:35
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- Registered: 01-06-2007
- Posts: 37
Re: H4531 - jumper function
Hello,
Thank you for your quick reply.
Yes you are right, but by mounting a 25K-ohms between data pin 1-2, you can have POE, on nonPOE devices.
Best regards,
Marin Constantin
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#4 19-10-2009 11:02:52
- HonzaD
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- Registered: 11-08-2008
- Posts: 294
Re: H4531 - jumper function
Hi,
That is right. But why this ... ?
John
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#5 20-10-2009 06:07:03
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- Registered: 01-06-2007
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Re: H4531 - jumper function
Hello,
Is called "cost reduction".
Why to spent 15euro/PoE receiver, when you just simply can use resistors - 5 euro/all.
We have a system with 21xH4531 and 2xT050. Using a Linksys-PoE 24 ports switch. And we still need 6xH4531 - plans for future.
And the costs for PoE receivers are around 300 euro - I know is not much, but with this money we can buy another H4531.
Best regards.
Marin Constantin
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#6 20-10-2009 06:44:13
- HonzaD
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- Registered: 11-08-2008
- Posts: 294
Re: H4531 - jumper function
Hi,
That makes sense.
Regards,
John
Last edited by HonzaD (20-10-2009 06:57:12)
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