ABB Symphony Harmony Series Instructions Manual page 47

Description
is online. Prior to removing a power supply tray, power to that
power supply tray must be switched off at the PEP. Failure to
do so may generate a PFI signal and cause a process upset.
In some cases, one redundant pair of power supply trays may
not provide all the power needs of the cabinet, thus requiring
the installation of two power chassis; however, each voltage
must be provided by only one power chassis. Do not attempt to
connect like voltages from two power chassis, as it will connect like voltages from two power chassis, as it will
connect like voltages from two power chassis, as it will connect like voltages from two power chassis, as it will
result in equipment damage. A typical use for two power chas- result in equipment damage.
result in equipment damage. result in equipment damage.
sis has the lower power chassis providing system voltages
(5 VDC, ±15 VDC) and the upper power chassis providing
power for field I/O (24 VDC, 48 VDC, or 125 VDC). Figure
shows the power chassis with redundant power supply trays
installed.
O U T P U T
T E R M IN A L B L O C K
2 5 .5 V
2 5 .5 V R E T
5 V R E T
5 V
S TAT U S O K
P O W E R S U P P LY
T R AY
Figure 2-3. Power Chassis (Power Supply Trays Installed)
2 - 4
R E A R V IE W
D IN R A IL F O R
M O U N T IN G D C B U S
M O N ITO R IN G A S S E M B LY
S TAT U S O K
FR O N T V IE W
P O W E R S U P P LY
T R AY
Do not attempt to Do not attempt to Do not attempt to
2-3
O U T P U T
T E R M IN A LS
P O W E R
C H A S S IS
T 0 4 4 5 9 A
WBPEEUI210509A1