ABB Relion REG670, Applications Manual

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Pole discordance protection CCPDSC will detect situation with deviating positions of
the poles of the protected circuit breaker. The protection has two different options to
make this detection:
• By connecting the auxiliary contacts in the circuit breaker so that logic is created,
a signal can be sent to the protection, indicating pole discordance. This logic can
also be realized within the protection itself, by using opened and close signals for
each circuit breaker pole, connected to the protection.
• Each phase current through the circuit breaker is measured. If the difference
between the phase currents is larger than a
CurrUnsymLevel this is an indication
of pole discordance, and the protection will operate.
9.9.3 Setting guidelines
The parameters for the Pole discordance protection CCPDSC are set via the local HMI
or PCM600.
The following settings can be done for the pole discordance protection.
GlobalBaseSel : Selects the global base value group used by the function to define
IBase , UBase and SBase as applicable.
Operation : Off or On
tTrip : Time delay of the operation.
ContSel : Operation of the contact based pole discordance protection. Can be set:
Off / PD signal from CB . If PD signal from CB is chosen the logic to detect pole
discordance is made in the vicinity to the breaker auxiliary contacts and only one
signal is connected to the pole discordance function. If the
Pole pos aux cont.
alternative is chosen each open close signal is connected to the IED and the logic to
detect pole discordance is realized within the function itself.
CurrSel : Operation of the current based pole discordance protection. Can be set:
Off / CB oper monitor / Continuous monitor . In the alternative CB oper monitor the
function is activated only directly in connection to breaker open or close command
(during 200 ms). In the alternative
Continuous monitor function is continuously
activated.
CurrUnsymLevel : Unsymmetrical magnitude of lowest phase current compared to the
highest, set in % of the highest phase current. Natural difference between phase
currents in 1 1/2 breaker installations must be considered. For circuit breakers in 1 1/2
breaker configured switch yards there might be natural unbalance currents through the
breaker. This is due to the existence of low impedance current paths in the switch yard.
This phenomenon must be considered in the setting of the parameter.
CurrRelLevel : Current magnitude for release of the function in % of IBase .
1MRK 502 071-UEN -
Section 9
Current protection
Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062 375
Application manual