Maximum of VMB8PB and VMB4PD modules on 1 bus

English
1

Am I right when I suppose that the maximum number of VMB8PB (30mA max consumption) and VMB4PD (27mA max consumption) modules is limited to +/- 33? (1000mA / 30mA consumption per module)?

When you need more than 33 modules, do you have to use a second bus? And how do you link the 2 busses than?

Thanks in advance
Klaas

2

This is the max. number of such modules per output of the power supply module.
As the power supply module outputs have the ground in common, you can continue with a second or third output if necessary.
Bus signals are separated from supply, so no problems there.

3

Indeed, I was confused.
thanks for the quick reply.

Klaas

4

Hello again,

still one little question: are 2 little cables of a UTP cat5e cable sufficient to power 18 VMB8PB + 3 VMB4PD modules that are present on my bus? Can such a cable deliver enough current?

And which is the best best cable to power all the velbus modules after a VMB3PS power module?

Thanks in advance
Klaas

5

[quote=“VEL417”]This is the max. number of such modules per output of the power supply module.
As the power supply module outputs have the ground in common, you can continue with a second or third output if necessary.
Bus signals are separated from supply, so no problems there.[/quote]

Maybe a small scheme is better than long words :wink:
ups.imagup.com/ano1/1286542696.jpg

6

Yes, I understand this perfectly, but my question was: can a UTP cable deliver sufficient current in order to feed all those 33 modules, are 2 wires of the UTP cable thick enough?

7

Sorry, my message wouldn’t hurt you but I think that lot of beginners in domotic (and without knowledge in electronic) would appreciate to have a clear view for this :slight_smile:

8

The best you can do is connecting 2 or 3 pairs of the UTP in parallel for the power supply.

9

That’s exactly what I did. Works like a charm…
Thanks !!