High-speed power contacts are part of the card BIO0007 with eight binary inputs
and three HSOs. They are optional alternatives to conventional BIO cards of the
protection relay.
3.12.2
Signal output contacts
Signal output contacts are single-pole, single (normally open/form A or change-
over/form C) signal output contacts (SO1, SO2,...) or parallel connected dual
contacts.
The signal output contacts are used for energizing, for example, external low
burden trip relays, auxiliary relays, annunciators and LEDs.
A single signal contact is rated for a continuous current of 5 A. It has a make and
carry for 0.5 seconds at 15 A.
When two contacts are connected in parallel, the relay is of a different design. It has
the make and carry rating of 30 A for 0.5 seconds. This can be applied for energizing
breaker close coil and tripping coil. Due to the limited breaking capacity, a breaker
auxiliary contact can be required to break the circuit.
When the application requires high making and breaking duty, it is
possible to use HSO contacts in the protection relay or an external
interposing auxiliary relay.
3.12.2.1
Internal fault signal output IRF
The internal fault signal output (change-over/form C) IRF is a single contact
included in the power supply module of the protection relay.
3
4
5
X100
IRF
Figure 40: Internal fault signal output IRF
3.12.2.2
Signal outputs SO1 and SO2 in power supply module
Signal outputs (normally open/form A or change-over/form C) SO1 (dual parallel
form C) and SO2 (single contact/form A) are part of the power supply module of the
protection relay.
1MRS757644 H
Basic functions
620 series
Technical Manual
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