The power supply/amplifier shall be Alpha Communications® / Elvox™ model 931, or approved equal. Amplifier shall operate from a standard 120VAC power source. All other wiring to power supply/amplifier shall be low-voltage Class II wiring, installed as per all federal, state, and local electrical codes. Power supply/amplifier shall surface mount right to the finished wall and shall be installed in a suitable environment that is free from excessive dirt, dust, temperature, humidity, grease and water. Power supply/amplifier shall provide the intercom amplification and signaling power for proper system operation. For most secure installation, power supply should be installed into a lockable equipment cabinet / housing. The 931 is designed to be used with the 870W, 8870 and 902 series apartment handset intercom units (or equivalent).
Power supply/amplifier shall be installed a safe distance from any source of electrical interference.
Contractor shall observe all local and national electrical and building codes.
The Alpha Communications® 931 amplifier/power supplies are used with the 870W, 8870 and 902 series handset intercom stations (or equivalent), to provide intercom amplification, power to operate the electric door opener(s) etc., and power to signal the handsets from the lobby entrance station.
The 931 units each require a standard 120VAC power source.
These 931 amplifier/power supplies are designed to easily surface mount right onto the finished wall by means of customer supplied screws. Connections are positive screw terminal type.
Only one (1) 931 is required for each system, regardless of the number of handsets in the building.
Height: 2.55" (65mm)
||Adjustable potentiometer built-in.
||Positive Screw Terminal Connectors.|
Basic intercom riser wiring shall be 4-common #22AWG, 2-common and 1 selective wire #22AWG, for each handset station on the riser. Add one (or more) additional common wires if other handset functions will be used. See system wiring diagram(s) for more complete wiring information.