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Option11C and 11C Mini TechnicalReference Guide
•Differential mode and common mode EMI filtering of input.
•Input power (-52VDC) for the Meridian Mail power supply (NTAK13).
DC power supply features
The DC power supply has the following features:
•Power (± 15V) for one attendant console.
•Generation of a system line transfer signal and power (-52V) for the
Power Fail Transfer Unit (250 MA maximum).
Voltage
The AC/DC power supply and the DC power supply provide +5.1, +8.5, +15,
-15V, -150V, -52V power supplies and filtered -48V.
There is a 1.0 second start-up delay on the +5V rail.
Ringing Generator
The AC/DC power supply and the DC power supply provide the ringing
generator for telephones:
•Ringing voltage: 70, 75, 80, 86V.
•Ringing frequency: 20, 25, 50 Hz, switch selectable.
•Ring sync: A pulse 500 us wide, 6 or 11 ms (±3 ms) before the positive
going zero crossing of the ringing waveform (11 ms for 20/25 Hz).
•Power: The output capability is 8VA which is capable of ringing 8CA4
ringers.
Power supply LED
The LED on the power supply faceplate labelled “DC” will be turned off
whenever there is a problem with the power supply.