TP-Link RX-7-248 - Manual (Page 31)

*Air Monitor (Ceiling Microphones)
In some cases the mixer control room is independent from the hall requiring sound
reinforcement, but the mixer operator must monitor the sound in the hall for mixer operation.
For this purpose, air monitor (ceiling microphones) inputs are provided on the phones module
and incorporate 48V DC phantom powering circuit for condenser microphones (e.g. TOA RD-
15C microphone).
* Power Supply Module
The power supply module (PSM-7) accepts DC power from the power supply unit (RPS-7) and
distributes it to each module. The PSM-7 is connected to the RPS-7 by an accessory umbilical
cable whose power switch will not turn "on" unless this connection is secure.
* Phantom Power Master Switch
A phantom power master switch is provided on the rear of the PSM-7. Phantom power is not
supplied to the IPM-7 and PHM-7, even at "on" positions of the phantom power switches on
these modules, unless the master switch is "on". In case condenser microphones are not being
used, the phantom master switch should be "off" to avoid potential problems which might be
caused by inadvertently turning a phantom power switch "on" on an IPM-7 or PHM-7.
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