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Technical Reference Manual, General
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The status of digital inputs can be inverted with parameters accessible through the
HMI or the Relay Setting Tool (Configuration\Digital inputs\Input
inversion). When inverted, the status of a digital input is TRUE (1) when no
control voltage is applied to the terminals, and FALSE (0) when the control voltage
is applied.
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The outputs are categorized as follows:
• HSPO: High speed power output, single or double pole contact, for example for
tripping purposes
• PO: Power output, single pole contact
• SO: Signal output, NO/NC (Normally open/Normally closed) contact
For detailed information about terminal connections, refer to the terminal diagrams.
Technical data of the outputs is found in the section "Technical data" on page 37.
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The high-speed power output HSPO1 can be connected as a double-pole output
where the object to be controlled (for example a circuit breaker) is electrically
connected between the two relay contacts, see the Figure 4.1.8.1.-1 below. The high-
speed double-pole power output is recommended to be used for tripping purposes.
HSPO1
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The high-speed power output HSPO1 can also be connected as a single-pole power
output where the object to be controlled (for example a circuit breaker) is electrically
connected in series with the two relay contacts, see the Figure 4.1.8.1.-2 below.
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