Low Auxiliary Voltage Indication - ABB RET 54 Series Technical Reference Manual, General

RET 54_
5.1.5.2.
36
Transformer Terminal
Technical Reference Manual, General
version is 18 V DC, medium version 80 V DC and high version 155 V DC. The
module PS1/48 V is a low version power supply and PS1/240 V is a medium or high
version. The type PS2/_ does not have binary inputs.
The auxiliary voltages of power supply modules and the corresponding rated input
voltages of digital inputs are:
Rated input voltage
Power supply module
of power supply
PS1/240 V (High) 110/120/220/240 V AC
or 110/125/220 V DC
PS1/240 V (Medium) 110/120/220/240 V AC
or 110/125/220 V DC
PS1/48 V (Low) 24/48/60 V DC
PS2/240 V 110/120/220/240 V AC
or 110/125/220 V DC
PS2/48 24/48/60 V DC
External display module 110/120/220/240 V AC
or 110/125/220 V DC
When RET 54_ is delivered with a fixed display module, the input voltage range of
the power supply module is marked on the front panel of the transformer terminal.
When the transformer terminal is provided with an external display module, the
input voltage of the display module is marked on the front panel of the module and
the input voltage of the main unit is marked on the side of the unit.
The external display module is only available together with a main unit equipped
with the PS_/240 power supply module.
The power supply version is specified by the first letter in the order number of RET
54_ (refer to Section "Ordering Information" on page 103). The voltage range of the
digital inputs is tied to the selected power supply. If a power supply version with the
higher rated input voltage is selected, the transformer terminals will be delivered
with digital inputs that also have the higher rated input voltage.
For further technical data of the power supply, refer to Table 5.2.1-2 on page 90.

Low auxiliary voltage indication

The RET 54_ transformer terminal is provided with a low auxiliary voltage
indication feature. The power supply module issues an internal alarm signal when a
drop in the power supply voltage is detected (ACFail, active low). The alarm signal
is activated if the power supply voltage falls about 10% below the lowest rated DC
input voltage of the power supply module, see the table below:
Rated input voltage
PS_/240
• Rated input voltage 110/125/ 220 V DC
• Rated input voltage 110/120/220/ 240 V AC
PS_/48
• Rated input voltage 24/48/60 V DC
1MRS755225
Rated input voltage
of digital inputs
220 V DC
110/125/220 V DC
24/48/60/110/125/220 V DC
-
-
-
Low indication level
99 V DC
88 V AC
21.6 V DC