Tips for updating older intercom system with a M&S DMC3-4 System


Step 1
Determine the model number of your current system. Model numbers are sometimes located on the front of the master station, on a swing open door covering room selector switches, on the bottom edge of the master panel, or on the back of the master station, requiring removal of the master from the wall.


Step 2
Determine the type of wiring currently installed. This could be a flat 4 or 3-conductor, 3-pair twisted or a variety of other configurations. Try and determine if an individual cable comes from each room station directly to the master station. Most systems require this configuration. Some Rittenhouse and Nutone systems use a daisy chain configuration. Systems using a daisy chain wiring scheme are not compatible with most intercom systems.


Step 3
Determine if your system includes ceiling speakers. If yes, determine if a separate volume control, or if the individual room station controls the speaker. Some M&S and Nutone system use a room station that can operate a ceiling, or separate wall speaker. A room station with this feature is not available with the DMC3-4 system. A separate volume control would be required for this situation.


Step 4
Measure your current room stations, patio and door stations if applicable. Adapter frames are available for most retrofits.


Step 5
Determine if your master station is connected directly to a 120-volt power source, and is not using a remote transformer. Most M&S systems have 120-volts right at the master. Some Nutone masters use remote transformer(s). If your system does not have 120-volts located at the master, 120-volt wiring will be required to update your system.


Step 6
If you are upgrading your master station and adding a CD changer, be sure to measure your vertical clearance. Some units are located between a counter-top and wall cabinet, limiting the vertical space available.


Note
The room stations used with the MC602 are compatible with the DMC3-4 system. All other systems require new room stations


Parts List
A typical parts list to replace most M&S intercom systems assuming 6 room stations, 1 patio station and door speaker are to be replaced would be as follows:

  • 1 ea. DMC3-4 Master station;
  • 1 ea. DMC1H Wall housing;
  • 1 ea. DMCFM Retro-fit frame for master station;
  • 1 ea. MC3 Chime module;
  • 6 ea. DMC4RS Room station;
  • 6 ea. DMCFR Adapter frame;
  • 1 ea. DMC4RW Patio station;
  • 1 ea. DMCFRW Retro-fit frame for patio station;
  • 1 ea. BD3BN Door station with button