Removing the Old System

Figure 1 – Transformer location

dmc3-4

Prior to removing the existing intercom system make sure all power is turned off at the intercom location. Remove the screws from the intercom master and while removing the intercom, make sure to carefully label each wire with its corresponding room location. Disconnect all the room station and door station wires from the master. Then carefully remove the existing wall housing and transformers.

If the existing system was not working prior to replacement, check each wire run between the room stations and master for shorts and wiring integrity. If one of these room station to master wire runs has a short, re-run that wire prior to installing the dmc3-4. When replacing wire runs use M&S Systems MS4XSC shielded wire. This wire will work for both 3 and 4-wire installations. On 4-wire installations use the wire as is and on 3-wire runs do not use the white wire.

Note: if you encounter 120VAC running through the existing wall housing, have a qualified electrician reroute the 120VAC around the wall housing.

If you encounter a remote transformer, an additional electrical run may have to be made by a qualified electrician to power the dmc master and/or optional CD player. Also check to make sure that the area around the housing is clear of any additional 120VAC runs or other obstructions.

Installing the Wall

Housing

The dmc1H and dmc1HC housings are designed for 16” on center studs. You may encounter stud spacings that vary from this standard. Use the dmc1H housing when you are replacing an existing system

with an intercom only system. The dmc1HC housing is used for

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