15
KUSAM-MECO Feb 2018
®
Note :
This function is not intended to identify the
effectiveness (trip current and trip time etc as
specified by the breaker manufacturers) of breakers.
Effectiveness of RCD circuit breakers should be
checked by RCD testing, measuring or monitoring
equipment under the scope of IEC61557-1 &
IEC61557-6.
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KUSAM-MECO Feb 2018
®
RST Phase Rotation Detection KM 69
As illustrated, connect test probes to voltage source
and observe indication. The tester should indicate
proper operating voltage level for good connections.
The Black probe (L1) connection is always
considered as the Reference-Phase* R.
—
If, however, annunciator
L
turns on, it indicates
that a “Left” phase-rotation is being detected.
rd
The Red probe
(L2)
connection is then the 3 Phase
nd
T.
The remaining unconnected connection is the 2
Phase
S.
Swap the two probe connections to get
reversed annunciator
R
, as for proper functioning
verification.
—
If annunciator
R
turns on, it indicates that a
“Right” phase-rotation is being detected. The Red
nd
probe
(L2)
connection is then the 2 Phase
S
. The
rd
remaining unconnected connection is the 3 Phase
T.
Swap the two probe connections to get reversed
annunciator
L
, as for proper functioning verification
Note :
This function works only on Y-connection
3P4W systems. It does not work on
Δ
-connection
3P3W systems that do not have an earth-ground
neutral. It, however, can work on High-leg
Δ
-connection 3P3W systems by using the high-leg
as the Reference-Phase
R
for Black probe
(L1)
connections. That is, simply test and find out the
high-leg which has the highest voltage (
Ö
3 times to
that of the other legs) with respect to earth-ground,
and use it as the Reference-Phase
R
for Black
probe
(L1)
connections. High-leg
Δ
-connection
systems have a center-tapped neutral connected to
earth-ground.
EF
RCD 30mA
230V
EF
EF
ELV
690
1000
400
230
120
50
24
12
RCD
+V
-V
-V
AUTO
V
12.6
ON
DCV-
+
EF
RCD 30mA
230V
EF
EF
ELV
690
1000
400
230
120
50
24
12
RCD
+V
-V
-V
AUTO
V
230
R
ON
ON
ACV
EF
RCD 30mA
230V
EF
EF
ELV
690
1000
400
230
120
50
24
12
RCD
+V
-V
-V
AUTO
V
230
R
ON
1
RCD
