Product specifications

Powering from an External Source Section 3 Configuration
176 3BSE036351-510 A
Powering from an External Source
The AC 800M Controller can be powered from an external +24 V DC source. This
source is often common for many different types of plant equipment, resulting in
long power cables to the AC 800M Controller. Furthermore, heavy load changes can
cause variations in controller supply voltage making it necessary to take precautions
against low voltage in order to prevent controller malfunction.
Should there be a risk that the +24 V at the PM8XX power terminals could drop
below 19.2 V for more than 1 ms, then an energy reservoir must be used for
Powering Units.
ABB requires the use of DC/DC converter and extra energy reservoir in case
external DC-supply with longer cables than 10 m is used.
For redundant power supplies to the AC 800M controller and associated units,
always derive connections from the SS8xx voting device. See
Figure 61 on page
177.