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Two power supplies in one line - Printable Version

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Two power supplies in one line - Jayce - 09.07.2018

Hello,

Is there a way to use two power supplies (640mA) in one knx line? Or is there any power supply with higher output than 640mA?

Thank you.

RE: Two power supplies in one line - Daniel - 09.07.2018

Hi
I think 640 is max for KNX line. Add repeater and then new PSU.
BR

RE: Two power supplies in one line - Gadjoken - 09.07.2018

(09.07.2018, 07:52)Jayce Wrote: Hello,

Is there a way to use two power supplies (640mA) in one knx line? Or is there any power supply with higher output than 640mA?

Thank you.

Hello,
It takes at least 200 meters between two power supplies. 
It is therefore necessary to put a coupler and a second power supply (second line).
B.R.

RE: Two power supplies in one line - Erwin van der Zwart - 09.07.2018

Hi,

KNX specifies that you can use a power supply on both ends of the line with a minimal distance of 200m between each PSU (to avoid over-current / burned cables on short circuit)

I have seen this in practice and it's very hard to maintain. When you have a power interruption in one of the PSU's the other one will go into overload error and you can only boot it up again by enabling the PSU's at the same time.

My advice is to never do this, and always use a line coupler with new PSU. 

BR,

Erwin

RE: Two power supplies in one line - AEK - 09.07.2018

you can by PSU 1280 mA (abb has it in their catalog)