Basic question, MOD-POE-V2

technoholic · January 26, 2016, 04:40:23 PM

If i\m reading the page for this product correctly, it seems that I can supply it with a maximum of 36v. How then can it work with a POE switch following 802.3af which it says that it complies with?

I must have read it wrong, so does it actually work with 48v from a standard POE switch? I want to use this for an in wall project and this is the missing part that I need.

MBR · January 26, 2016, 08:03:36 PM

It's probably just an ambiguity wording in the in the descrition/documentation, the circuitry seems to be capable handling 36V without problems (the Si3402-A-GM itself shoud handle up to 57V, see http://eu.mouser.com/ProductDetail/Silicon-Labs/Si3402-A-GM/?qs=rwDsHg%2F73nI6yTyK3hqp2Q%3D%3D). IMHO, the 36V is the maximal minimal voltage required for POE-V2 to work, so you must supply at least 36V to work reliably all the times, but it can work with lower voltages too (but without guarantee).

technoholic · January 26, 2016, 09:39:00 PM

If that's true then that's great, I've ordered one now anyway, but be good to hear from anyone who has actually used it in this way. I've seen the data sheet you linked and like you say it certainly says it can handle voltage up to 57v so hopefully it will be fine

LubOlimex · January 27, 2016, 10:21:51 AM

Hey there,

MOD-POE-V2 complies with the 802.3af-2003 standard. We test each board at 50V.

The FAQ section of the product's page says that it will not work with less than 30V and the maximum start-up threshold is 36V.

Best regards,
Lub/OLIMEX

technoholic · January 27, 2016, 12:00:36 PM

That's great, good news it will work with a standard 802.3af switch.

Can you tell me what size the DC barrel connector is? And if it is tip-positive or tip-negative?

Thanks

technoholic · January 27, 2016, 03:05:06 PM

Actually not to worry, it seems that its a 2mm pin size and tip is negative if I'm reading the schematic right.

I've looked but cannot find this - can you tell me if there is a part that would be suitable to replace the DC jack with a vertical mount version, as well as the RJ45 socket?

JohnS · January 27, 2016, 04:31:34 PM

I think you may be wrong about the polarity (if I've understood you).

The size may well be 2.1mm but do check carefully.

John

technoholic · January 27, 2016, 05:27:09 PM

i think you're right, i think i was looking at it wrong! Anyway i'll double check with a meter when it arrives

LubOlimex · January 28, 2016, 08:37:37 AM

The power jack is described here: https://www.olimex.com/wiki/PWRJACK

Best regards,
Lub/OLIMEX

technoholic · January 28, 2016, 03:52:06 PM

Thanks, received the board today, works great so will be ordering a few more.

Thanks

gregoryvaughn · August 11, 2016, 08:58:54 AM

Quote from: technoholic on January 26, 2016, 04:40:23 PM
If i\m reading the page for this product correctly, it seems that I can supply it with a maximum of 36v. How then can it work with a POE switch following 802.3af which it says that it complies with?

I must have read it wrong, so does it actually phenq reviews work with 48v from a standard POE switch? I want to use this for an in wall project and this is the missing part that I need.

good to see it is working okay for you.
I provide 24V to the input of MOD-POE-V2 but there is no output. What can be the problem?

LubOlimex · August 24, 2016, 09:32:41 AM

Hey,

QuoteI provide 24V to the input of MOD-POE-V2 but there is no output. What can be the problem?

The problem is that it will not start at all with less than 30V DC...

As the FAQ section at the bottom of the product page says:

Si3402 has a minimum of 30V start-up threshold (36V maximum start-up threshold). Please provide 36V to LAN+POE_IN and check again.

You can find more about the voltage requirements of the equipment that complies with IEEE 802.3af-2003 here: https://en.wikipedia.org/wiki/Power_over_Ethernet

Best regards,
Lub/OLIMEX