Furman Sound PS-PRO II - Manual (Page 3)

P S - P R O I I - P O W E R C O N D I T I O N E R / S E q u E N C E R
lIFT (
l i n e a r f i lt e r i n g
t e c h n o l o g y
)
Unfortunately, traditional AC filter - conditioners
have been designed for unrealistic laboratory
conditions. Prior technologies, whether multiple
pole filter or conventional series mode, could
actually harm audio and video performance
more than they help, due to the resonant peaking
of their antiquated, non-linear designs. Under
certain conditions, these designs can actually
add more than 10 dB of noise to the incoming
AC line! Worse still, lost digital data, the need
to re-boot digital pre-sets, or destroyed digital
converters are frequently caused by excessive
voltage spikes and AC noise contaminating the
equipment ground. Furman’s SMP+ with LiFT
takes another approach, ensuring optimal per-
formance through linear filtering and no leakage
to ground.
D ESCRIPTION
The PS-PRO II is a power sequencer, meaning it
is capable of powering a rack full of equipment in
three steps separated by timed delays. It is use-
ful whenever various kinds of equipment must
be powered up or down in groups, rather than
simultaneously. In audio systems, sequenced
powering is often necessary to allow turn-on
transients from low level amplifiers and pro-
cessors to settle down before any power amps
are turned on, because simultaneous powering
would result in a loud, annoying, and potentially
destructive “pop” reaching the speakers. And in
any large system whose components present an
inductive load to the AC line (including electric
motors, power supplies, and power amplifiers
of all kinds), sequenced powering can avoid
excessive inrush currents that can cause circuit
breakers to trip, even though the steady-state
currents are not excessive. Power sequencing
is particularly suited to applications where large
installations must be switched by inexperienced
personnel.
The PS-PRO II is controlled by a front panel
key-operated switch to provide security from
non-authorized users tampering with the sys-
tem. The switch has three positions: OFF, ON,
and REM, allowing for local or remote control.
With remote control, one or more PS-PRO II’s
may be installed in remote locations with on/off
control and LED monitoring via low-voltage
control wires.
Besides its power sequencing capabilities, the
PS-PRO II contains many other conditioning and
protection features. Each aspect of its functioning
will be discussed in the next sections.
INSTallaTION
RECOmmENDaTIONS
In audio/video installations, we recommend that
power amps receive power last — plug them all
into Delay 3 or divide them into two groups and
plug one group through Delay 2 and the other
through Delay 3. Low level equipment such as
mixers and signal processors should use Delay
1. Equipment incorporating clocks or timers such
as VCR’s, or equipment that must respond to
wireless remote actuation, should use the un-
switched outlets. We suggest keeping the front
panel's unswitched outlet free for equipment that
is only in use temporarily.
The overall capacity of the PS-PRO II is 20 amps.
This refers to the combined steady-state current
drawn by all devices plugged into all of its nine
outlets. If this combined current level exceeds
20 amps at any time, the circuit breaker will trip,
cutting off power to your rack. If this occurs, you
must reduce the load by unplugging one or more
units from the PS-PRO II. Then push the black
button on the circuit breaker (on the front panel)
to reset it.
2