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The type CCP13E relay is a very sensitive induction-cylinder power-directional relay
for three-phase alternating-current circuits.
The relay consists of three single-phase directional units with the three rotors
mounted on a single shaft.
separate contacts, one normally open and one normally closed.
contacts are held closed by two spiral springs that also complete the control
circuits to the moving contacts.
the normally-open contact.
The CCP13E relay is functionally equivalent to the CCP13D relay, but the two relays
are not electrically interchangeable.
arrangement s.
Because of its sensitivity and its real power-directional characteristics,
CCP13E relay finds application where it is important to detect extremely small
reverse power flow.
direction of power flow is always in the same direction.
such an application is illustrated in Figure 1.
Consider the section of a system shown in Figure 1 with normal load flow from the
system to the load.
be cleared at source
#2.
transformer
However, it is desirable to open circuit breaker
ground fault completely.
with circuit breaker
real component of the exciting current (this is the core-loss component) taken by
the transformer through circuit breaker
Since the CCP13E is very fast and very sensitive, it might operate for system
disturbances that result in momentary reversals of power through one or the other of
the two banks.
For this reason, the CCP13E should be used in conjunction with some
time delay when applied as discussed above.
Before the CCP13E is applied, certain calculations should be made to check the
sensitivity
of
the
assoc iated transformer,
illustrated in the section titled
transformers (CT•s) that supply the CCP13E relay should be selected with the lowest
possible ratio without exceeding the
GEK-65525
THREE-PHASE POWER-DIRECTIONAL RELAY
TYPE CCP13E
DESCRIPTION
The contact assembly consists of two electrically
There is a target and seal-in coil in series with
APPLICATION
This application is restricted to cases where the normal
If a single-phase-to-ground fault were to occur at F, it would
#2,
but not necessarily at breaker
This can be accomplished by the CCP13E relay associated
#2.
The CCP13E is generally sensitive enough to operate on the
relay,
against
the
to ensure proper operation.
SAMPLE CALCULATIONS.
5.0
There are differences in the output circuit
#2
#2
when sou r ce
is removed.
2
shows how this can be done.
Figure
available
core-loss
ampere continuous rating of the relay.
3
The normally-closed
The classical example of
#2
because of delta-wye
#2
to clear the
component
A sample calculation is
In general, the current
the
of
the
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