ABB AC 800M

Appendix A Hardware Units SS822 Voting Unit – (for Redundant Power Supply)
3BSE 027 941 R301 189
SS822 Voting Unit – (for Redundant Power Supply)
Redundant Power Supply Configurations
The SS822 Voting Unit has been specifically designed for utilization as a control
unit within a redundant power supply configuration. The output connections from
two identical Power Supply Units (PSUs) are connected to the SS822, see Figure 31
on page 106 and Figure 32 on page 107.
The SS822 Voting Unit separates the redundant PSUs, supervises the voltage
supplied and generates supervision signals to be connected to the computer system.
Green LEDs, mounted on the SS822 front panel, provide a visual indication that the
correct output voltage is being delivered. Immediately the green LED lights up, a
voltage-free contact closes the path to the corresponding "OK connector". The
SS822 trip levels (2 off), are factory preset. For details see Table 56 on page 190
SS822 Voting Unit – Supervision Data.
Figure 47. SS822 Voting Unit Connections
OK F
OK
A+B+L+
SS822
F
+
+
AB
L+L–
44 mm
97 mm (3.8 in)
110 mm (4.3 in )
103 mm (4.1 in)
(1.7
in
)
125 mm
(4.9
in
)
50 mm (2.0 in)