KCQ333x2 provides both visual speed rotation, phase angle relationship and raise/lower speed relay signals necessary to achieve automatic check synchronising of two different system voltages.
is the standard and it takes the auxiliary voltage from the monitored voltage on terminal 3 & 4.
The synchronising relay will close when the incomer (generator, busbar, etc.) voltage and phase angle have been within the limits during the set retention time.
There is lamp indication for reference source present (BUS PWR, only when generator is powered) and incomer status (GEN PWR).
function can inhibit synchronising. This feature allows the operator to determine the moment to enable synchronising. Open link between terminal 7 & 8 to inhibit. LED "CB CLOSE" flashes during inhibit condition.
KCQ333x2 can be used both for single and three phase systems. Any two phases (or phase-neutral) can be used for synchronising as long as it is the same two phases on both side of the breaker.
The unit is meant for manual and semi-automatic synchronising only since there is no compensation for the breaker closing time.
For automatic synchronising, the KCQ104x2 "SPOT ON" principle should be used to obtain compensation for breaker closing delay.
User settable voltage limits, retention time, phase angle and pulse rate and width on the front of the unit.
The analogue -10/0/+10mA output signal can be used as speed reference to
a generator controller, with polarity and amplitude proportional to
frequency difference between the two systems.
System status:
KCQ333x2 is fitted with a system status relay. As standard the unit is powered from generator side (terminal 3 & 4), when power is ok and unit is working correctly the relay activates. It will release on alarm or when unit is not powered. Separate auxiliary supply is needed for continuously system status.
Normal operation : Closed contact
Alarm condition/unpowered : Open contact
System "S" the sector synchronising principle
The KCQ333x2 is a low differential bi-directional check synchronising relay.
The synchronising relay closes when the incomer (generator, busbar,
etc.) frequency is close enough (diff 0,018 - 0,83Hz) to stay within the
phase angle sector (S) for the set retention period (t).
Sector synchronisation is the classic alternative for applications which
allow synchronisation accuracy and duration of synchronisation process
to be interrelated. There is no compensation for the breaker closing
time.
Approximate synchronisation accuracy relative to 12 o’clock position (Df) can be calculated by the following formula:
Df = (S : 360) / t (secs)
Example: Set phase angle (S) to 10 degrees and retention time (t) to 500mS to obtain an accuracy of Df:
(10/360) / 0,5 = 0,055Hz
If the phase angle limit is set too low and retention time too high for
very low differential synchronising, it can be difficult to achieve
synchronisation. If there is a continuously fluctuating load between the
two systems (for example to synchronise against a shaft generator when a
vessel is in rough weather), the KCQ104x2 "SPOT-ON" principle is more
suitable.
The "phase angle" setting on the front of the unit refers to the total
phase angle sector (S), centred about 0°. Hence a setting of 10° means
the sector spanning from -5° to +5°.
Note: The CB Close LED will flash when unit is ready for synchronising, but inhibit input is open or synchronising mode is not selected.
