Sonix 350-d Technical Manual
3.4.4 Hot Standby Bus and Hot Standby amplifi er
The Hot Standby ports provide a backup 100 V Line that
will be used in the case of an amplifi er failure. It allows
Hot Standby amplifi ers to drive the speaker load of any
connected faulty 350-d unit.
The Hot Standby bus connections are only between the
350-d units. Units are daisy-chained similarly to the Amp
Bus. All connections are top port to bottom port, as per
diagram below:
Hot Standby
Amp Bus
EOL-8 Bus
Fuse
Danger - Hazardous Voltages Present!
COMPLIANT
Amp
Fault
O/P
N/C
com
PSU
Fault
O/P
N/C
com
48 V
DC
I/P
+ -
Sonix 350-d
#3 Hot Stand-by
Hot Standby
Amp Bus
EOL-8 Bus
Fuse
Danger - Hazardous Voltages Present!
COMPLIANT
Amp
Fault
O/P
N/C
com
PSU
Fault
O/P
N/C
com
48 V
DC
I/P
+ -
Sonix 350-d
#2
Hot Standby
Amp Bus
EOL-8 Bus
Fuse
Danger - Hazardous Voltages Present!
COMPLIANT
Amp
Fault
O/P
N/C
com
PSU
Fault
O/P
N/C
com
48 V
DC
I/P
+ -
Sonix 350-d
#1
Hot Standby
Amp Bus
EOL-8 Bus
Fuse
Danger - Hazardous Voltages Present!
COMPLIANT
Amp
Fault
O/P
N/C
com
PSU
Fault
O/P
N/C
com
48 V
DC
I/P
+ -
Sonix 350-d
#6 Hot Stand-by
Hot Standby
Amp Bus
EOL-8 Bus
Fuse
Danger - Hazardous Voltages Present!
COMPLIANT
Amp
Fault
O/P
N/C
com
PSU
Fault
O/P
N/C
com
48 V
DC
I/P
+ -
Sonix 350-d
#5
Hot Standby
Amp Bus
EOL-8 Bus
Fuse
Danger - Hazardous Voltages Present!
COMPLIANT
Amp
Fault
O/P
N/C
com
PSU
Fault
O/P
N/C
com
48 V
DC
I/P
+ -
Sonix 350-d
#4
To Eol-8
To Eol-8
To Eol-8
To Eol-8
To Eol-8
To Eol-8
To Eol-8
To Eol-8
Figure 7. Hot Standby bus connections.
Warning:
Hot Standby cables carry 100 V audio
power line; Electrical Shock Risk warning labels
need to be fi tted on both ends.
Any unit in a chain can be confi gured to be the Hot
Standby amplifi er (see 5.5). The recommended location
for placing the hot standby amplifi er is either above or
below the bank of associated amplifi ers.
The Hot Standby amplifi er is not connected to the Eol-8
unit, its top and bottom EOL-8 ports must be linked
together instead, as per Figure 7 above. This connection
is mandatory to enable 100 V output onto the Hot
Standby bus and maintain the Healthy status of the
system and is referred to as EOL loopback.
While there is no technical limit on how many amplifi ers
a single Hot Standby amplifi er should support, practical
considerations should be taken into account. Eaton
suggests that a minimum of 1 and maximum of 8
amplifi ers is a sensible starting point for a system.
ote:
N
There can be more than one Hot Standby amplifier, each with its
own chain of amplifiers connected in a Hot Standby loop.
Warning:
Only confi gure one 350-d amplifi er as
a Hot Standby per Hot Standby Bus loop.
13
SONIX 350-D TECHNICAL MANUAL
TM367 / A May 2022 www.eaton.com
