K8AB-PH1 Omron, K8AB-PH1 Datasheet - Page 6

• Manufacturer Part Number: K8AB-PH1
• Description: 3-phase Seq Loss Ry.200-500
• Manufacturer: Omron
• Series: K8ABr

Specifications of K8AB-PH1

• Contact Form: SPDT
• Coil Voltage: 200 VAC to 500 VAC
• Contact Rating: 6 A at 250 VAC
• Mounting Style: DIN Rail
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: K8ABPH1; Z2806

Connection Diagram
6
Q
Q
Checking Operation
Phase Sequence
Phase Loss
Can phase loss be detected on the load side?
In principle, phase loss cannot be detected on the load side
because the K8AB-PH1 measures three-phase voltage to
determine phase loss.
Switch the wiring, as shown by the dotted lines in the
connection diagram, to reverse the phase sequence and
check that the K8AB operates.
Create a phase loss for any input phase and check that the
K8AB operates.
Questions and Answers
L1
L2
L3
Phase-sequence Phase-loss Relay
3 ,
200 VAC
L1
L2
L3
K8AB-PH
Characteristic Curve Diagram
Note: For phase loss of phase R. V
Q
terminal voltage at phase loss.
Motor Load Phase Loss during Operation
Motor load phase loss cannot be detected during operation.
It can be used to detect phase loss at startup.
Normally, three-phase motors will continue to rotate even if
one phase is open. The three-phase voltage will be induced
at the motor terminals. The diagram shows voltage induction
at the motor terminals when phase R has been lost with a
load applied to a three-phase motor. The horizontal axis
shows the motor load as a percentage of the rated load, and
the vertical axis shows voltage as a percentage of the rated
voltage. The lines in the graph show the voltage induced at
the motor terminals for each load when phase loss occurs
during operation. As the graph shows, voltage is induced at
the motor terminals even if there is phase loss for a motor
load, so the K8AB-PH1 cannot detect phase loss for motor
loads during operation. Use the K8AB-PH1 to detect phase
loss at startup.
100
Note: This characteristic curve shows the approximate
95
90
85
80
75
70
65
60
55
50
45
0
values only.
10
20 30 40 50 60 70 80 90 100 110
Motor load (as a percentage of rated load)
ST
, V
TR
, and V
Cat. No. N145-E1-02
RS
indicate the motor
V
V
V
ST
TR
RS