Visonic MCR-308 and MCX-8 Expander

[caravanboy]

Hi,

I\'ve nearly finished commissioning my Comfort system. I have used a Visonic MCR-308 receiver for wireless elements - I used Visonic kit years ago, they\'re very reliable and great.

Anyway, I have a Comfort panel and a SEP panel but they\'re not located near to each other and I can\'t easily run extra cables between them and I only have a few spare wires.

The main wireless receiver is connected to the SEP but I\'ve changed plans and need to add more wireless zones. So, I\'ve got a Visonic MCX-8 expander on order. I need to connect the MCR-308 and MCX-8 to each other with 4 wires (for Visonic\'s own bus - 0v, 12v and 2 x data lines). I don\'t have enough spare zones on the SEP so the expander\'s outputs will have to connect to the main Comfort panel.

My query is... am I okay connecting the Open Collector outputs of the expander direct to Comfort zones when the 12v supply on that expander unit is coming from a different power supply?  The MCX-8 is powered by the SEP but it\'s outputs will be connected to the zones on the main Comfort panel. All units have the same common/0v so I think I\'m okay, but can anyone confirm?

The attached diagram should make it really clear.

Thanks

[slychiu]

I beleive this should work since the grounds are common

[caravanboy]

Great, thanks for the speedy reply.