SE-K2EN Omron, SE-K2EN Datasheet - Page 11

• Manufacturer Part Number: SE-K2EN
• Description: RELAY MOTOR PROTECT 200/220/240V
• Manufacturer: Omron
• Series: SEr

Specifications of SE-K2EN

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: SEK2EN

■ Checking Operation
Troubleshooting
■ Calculating the Unbalanced
The unbalanced factor can be obtained easily from the following
graph. In the graph, the horizontal axis indicates the phase of the
maximum current, whereas the two vertical axes indicate the remain-
ing two phases. Taking the phase of the maximum current with a ref-
erence value of 1.0, the unbalanced factor is obtained in percentage
from the curves centered in the graph.
When the motor current I
the ratios of the currents, setting the value of the maximum current to
1. In this case the ratios are 1 : 0.6 : 0.7 (I
To find the unbalanced factor, follow the arcs from the ratio values on
the vertical axes, in this case 0.6 and 0.7, to their intersection point.
The unbalanced factor can be estimated from the values on the
graph. Here the unbalanced factor is approx. 36%.
Checklist After Connection and Before Starting Motor
Relay operates before the motor starting time has
elapsed. (OPEN indicator)
Relay operates after the motor starting time has
elapsed. (OC indicator)
Motor circuit is not tripped when the relay oper-
ates following the depression of the test button.
Relay doesn’t operate properly under light loads. 1. Check each phase for an unbalance of more than 35%, and also check for waveform dis-
Check the Current Converter for the proper number of
conductor runs through holes and the proper direction.
Check the Current Converter and Motor Protective Relay
for connection with proper polarity.
Check the phase-sequence of 3-phase voltage (for 3E
relays).
Factor
Trouble
R
= 100 A, I
s
= 60 A, and I
R
: I
S
: I
T
).
T
1. Is there any open-phase trouble in the motor or its circuit (fuses, electromagnetic contac-
2. Does the Current Converter have the correct number of conductor runs through holes?
3. Is the supply voltage or motor current unbalanced (unbalanced factor of more than 35%)?
1. Does the set current match the motor current?
2. Does the set operating time match the motor starting time?
3. Does the Current Converter have the correct number of conductor runs through the holes?
1. Disconnect terminals 4, 5, and 6, (Ta, Tb and Tc with the flush mount type) and check the
2. If the open-phase unbalance sensitivity switch is set to “H”, then switch it to “L”.
3. If the switch is already set to “L”, then the open-phase ON/OFF switch can be set to OFF,
= 70 A, calculate
tors, wiring)?
Does the conductor run in the proper direction?
relay contacts for electrical continuity.
tortion.
but the open-phase function will be disabled.
Test Operation
Corrective action
Press the test button (for
longer than the set time).
Does the relay
operate?
NORMAL
YES
Check Points
Apply control
power supply
to the relay
NO
Relay operates instantaneously
Check for:
1. Loose terminal screw
2. Faulty reset of trip
3. Low voltage at power
Change the phase-
sequence of 3-phase
voltage properly.
indicator
supply
SE
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