Operating Voltage; Grounding (Earthing) - Zenith 10K4 User Manual

5.4 Operating voltage

The label placed to the right of the mains
cable on the rear of the amplifier indicates
The AC mains voltage for which the amplifier is wired
and approved: 230V. Connect the power cable only
to the AC source type referred to on the label. The
warranty will not cover damage caused by
connecting to an incorrect type of AC mains.
10K4 switch mode amplifiers use primary switching.
Because the mains power is rectified directly before
the transformer, the amplifier is insensitive to mains
frequency. It may be connected to 50 or 60Hz
sources, and actually will operate on line
frequencies from DC to 400Hz.
10K4 amplifiers use PowerCON mains input
connections. If the power plug mounted at the
factory is not appropriate for your country, it can be
removed and the proper connector wired in its place
as follows:
Wire distribution:
Brown
Blue
Green and yellow
LIVE
NEUTRAL
EARTH (GROUND)
If you are not 100% confident of your
competence to replace the mains plug,
engage qualified personnel to do the job.
Once a suitable AC supply is connected, the
amplifier can be turned on using the front panel
power switch. The amplifier then goes through a
soft-start. The fans will blow at high speed before
dropping to idle, and the power, LED will illuminate.
Inrush power is controlled and limited during soft-
start, enabling multiple amplifiers to be powered up
simultaneously.

5.5 Grounding (earthing)

There is no ground lift switch or terminal on the
10K4 amplifiers. The signal ground is always
floating, via a resistor, to chassis and therefore the
grounding system is automatic.
In the interests of safety, never disconnect the earth
(ground) pin on the AC power cord.
Use balanced input connections to avoid hum and
interference.
Zenith 10K4 Amplifier Manual 10