sundance-communications.com/forum Forums TDM Business Telephone Systems Nortel Telephones & Systems BCM400 Media Bay Module DIP Switches

Any easy way to understand the switch settings on Media Bay Modules? I'm installing a 4X16 mod on a new expansion cab. I've looked at nortels book and came out more confused. I'm on a 6/2 split.
I believe that means I can use buses 2 through 6 for media mods. Do I have to use of these buses for the 4X16 mod? Hope someone can explain this to me in a way I understand. Thanks for any help.

A 2/6 split means that you have buses 2-7 available unless a module requires two buses. Then 6 is the last usable buss for that module.
Just like your 4x16. That uses two buses so the last bus avail for dip switch settings will be 6.

The NORMAL way the BCM buses works are: You NORMALLY set your stations low bus first working upward. Trunks you set at the higher bus and work your way down.
But then along came the COMBO module.
The 4x6 has both trunks & stations.
You set the dips for the first bus which is for the TRUNKS. Then it Automatically uses the next bus for the stations. Example: if you set the dips for bus 4, that is the Trunk bus. Then it grabs bus 5 for the stations.

I normally put 32+ modules first - at buss 2. If I have a second one, then it goes to buss 3. If I have a DTM it goes in buss 7. Then if more Analog Trunks they go in 6.
The 4x16 would go to the first open lower bus.
It does not really matter which bus for which module as long as you don't put the dips the same for two modules.
But if you use this method, it keeps the DN's in better order and the same for trunk Line numbering.

That is it in simple terms. You can get deeper if you use offsets.

Thanks, i'm thinkin its them offsets I don't quite understand despite reading the Nortel book on setting them. Nortel's Docs on this are not easy to understand. I'm figuring to just go do it and make notes on what works.

I'm not getting a warm and fuzzy feeling. It may work now, but what happens if you need to expand again. You need to understand what you are doing or you may unintentionally block resources.

It's best to know what you are doing or pass the job to someone who does. Clients both deserve and expect they are hiring someone who knows what they are doing and paying for expertise, not someone willing to trial and error their system.

The easiest way to remember dip switch settings is by using the binary code.

And yes offsetting can be upsetting if you are not sure, like Marv said.