CSM_K2CU_DS_E_3_2
1
Heater Element Burnout Detector
K2CU
Accurate Detection of Heater Element
Burnout Regardless of Heater Capacities
• Accurately detects a burned heater element or elements incor-
porated by a molding machine or packing machine and outputs
an alarm signal.
• Precisely singles out the burned element even if one heater el-
ement among several heater elements has been burned out.
• Applicable to small- to large-capacity heater elements.
• All K2CU-F large-capacity, built-in current transformer models
work with both single-phase and three-phase heaters.
• Voltage fluctuation compensation function eliminates false
alarms due to variations in the supply voltage.
Model Number Structure
■Model Number Legend
1. Heater Element Burnout Detector
2. Operation
F: Large-capacity, built-in Current Transformer model
P: Small-capacity plug-in model
3. Operating Current Range
0.5: 0.25 to 0.5 A
1: 0.5 to 1 A
2: 1 to 2 A
4: 2 to 4 A
10: 4 to 10 A
20: 8 to 20 A
40: 16 to 40 A
80: 32 to 80 A
4. Voltage Compensation
None: Not provided
A: Provided
5. Control Power Supply Voltage
A: 100/200 VAC
B: 110/220 VAC
C: 100 VAC
D: 110 VAC
E: 200 VAC
F: 220 VAC
6. Gate Input
None: Not provided
GS: Provided
Ordering Information
K2CU-F@@A-@GS Model with Gate Input Terminals
Note: A model with a gate input terminal is required to combine the K2CU with a temperature controller that uses PID control for temperature control of a heater. To do
so, use a temperature controller with a voltage output.
123 4 5 6
K2CU-@@@-@@
Control supply voltage Operating current
4 to 10 A 8 to 20 A 16 to 40 A 32 to 80 A
100 VAC With voltage fluctuation compensation K2CU-F10A-CGS K2CU-F20A-CGS K2CU-F40A-CGS K2CU-F80A-CGS
110 VAC K2CU-F10A-DGS K2CU-F20A-DGS K2CU-F40A-DGS K2CU-F80A-DGS
200 VAC K2CU-F10A-EGS K2CU-F20A-EGS K2CU-F40A-EGS K2CU-F80A-EGS
220 VAC K2CU-F10A-FGS K2CU-F20A-FGS K2CU-F40A-FGS K2CU-F80A-FGS
K2CU
2
K2CU-F Large-capacity, Built-in Current Transformer Models
K2CU-P Small-capacity, Plug-in Models
Specifications
■Ratings
■Characteristics
Note: The logical value is an operating value within a range of 0.85 to 1.1 with a voltage fluctuation of 85% to 110%, based on the value at the control supply voltage
measured as 1.
Control supply voltage Operating current
4 to 10 A 8 to 20 A 16 to 40 A 32 to 80 A
100 VAC With voltage fluctuation compensation K2CU-F10A-C K2CU-F20A-C K2CU-F40A-C K2CU-F80A-C
110 VAC K2CU-F10A-D K2CU-F20A-D K2CU-F40A-D K2CU-F80A-D
200 VAC K2CU-F10A-E K2CU-F20A-E K2CU-F40A-E K2CU-F80A-E
220 VAC K2CU-F10A-F K2CU-F20A-F K2CU-F40A-F K2CU-F80A-F
Control supply voltage Operating current
0.25 to 0.5 A 0.5 to 1 A 1 to 2 A 2 to 4 A
100/
200 VAC
With voltage fluctuation compensation K2CU-P0.5A-A K2CU-P1A-A K2CU-P2A-A K2CU-P4A-A
Without voltage fluctuation compensation --- K2CU-P1-A K2CU-P2-A K2CU-P4-A
110/
220 VAC
With voltage fluctuation compensation K2CU-P0.5A-B K2CU-P1A-B K2CU-P2A-B K2CU-P4A-B
Without voltage fluctuation compensation --- K2CU-P1-B K2CU-P2-B K2CU-P4-B
Item K2CU-F K2CU-P
Control supply voltage 100, 110, 200, 220 VAC 100/200, 110/220 VAC
Rated frequency 50/60 Hz
Carry current 1.25 times as large as each model’s maximum operating cur-
rent
2.5 A for K2CU-P0.5A-A/-B;
5 A
Operating voltage range 85% to 110% of control supply voltage
Voltage fluctuation compensation
range
85% to 110% of control supply voltage 85% to 110% of control supply voltage (applicable only on
models with voltage fluctuation compensation)
Operating current 4 to 10 A, 8 to 20 A, 16 to 40 A, 32 to 80 A (continuously vari-
able)
0.25 to 0.5 A, 0.5 to 1 A, 1 to 2 A, 2 to 4 A (continuously vari-
able)
Releasing current 105% max. of operating current 110% max. of operating current
Operate time 0.5 s max. (when current changes from 150% to 0%)
Gate input voltage range (for models
with gate input terminals)
5 to 30 VDC ---
Control output 2 A at 220 VAC, SPDT (cosφ = 0.4)
Power consumption Input: 0.5 VA max.
Power supply: 5 VA max.
Input: 1 VA max.
Power supply: 4 VA max.
Setting accuracy ±7% max.
Repeat accuracy ±3% max.
Influence of temperature ±10% max. (at 20°C±30°C)
Influence of voltage Models without voltage fluctuation compensation:
±3% max. of the value measured at the control supply voltage, on condition that the voltage fluctuation is 85% to 110% of
the control supply voltage
Models with voltage fluctuation compensation:
±5% max. of the logical value, on condition that the voltage fluctuation is 85% to 110% of the control supply voltage. (see
note)
Influence of frequency ±3% max. (at ±5% of rated frequency)
Insulation resistance 10 MΩ min. (at 500 VDC) between electric circuits and mounting panel
Dielectric strength 2,000 VAC, 50/60 Hz for 1 min between electric circuits and mounting panel
Overcurrent 20 times of max. set value of operating current for 2 s
Vibration resistance Destruction: 16.7 Hz, 1-mm double amplitude for 10 min each in X, Y, and Z directions
Shock resistance Destruction: 98 m/s2 (approx. 10G)
Ambient temperature Operating: –10°C to 55°C (with no icing)
Ambient humidity Operating: 45% to 85%
Weight K2CU-F: approx. 390 g; K2CU-P: approx. 300 g
K2CU
3
Operation
K2CU-F@@A-@GS Series
When power is supplied to the heater (when the SSR is ON), a cur-
rent flows through the wires to the heater elements. At the same
time, a voltage is imposed on the gate circuit and the K2CU-
F@@A@GS begins monitoring the current flowing through the heater
wires.
The current flowing to the heater wires is detected by the detector
sections through each Current Transformer (CT) incorporated by the
K2CU-F@@A-@GS.
The current signals transmitted by the two CTs are sent to the cur-
rent-voltage converters, smoothing circuits, and comparators as
shown in the diagram.
The signal generated by the reference voltage generator is sent to
the setting circuit to provide a reference value. The reference value is
sent to the comparators. Each comparator compares its heater ele-
ment current input and the reference value. If the input is lower than
the reference value, a signal is sent to the output circuit.
There are two detector sections operating independently. If either of
the input signals from the CTs is lower than the reference value, the
output relay and alarm indicator will be activated.
The K2CU-F@@A-@GS incorporates a voltage fluctuation compen-
sation function which automatically corrects the reference value if the
supply voltage fluctuates.
Temperature
controller
Heater elements
Power supply
To each circuit
Note: 1. The dotted lines indicate the line conductors passing through the windows of the current transformers.
G+ G−S1S2
b1
a1
CM
1
SSR DC
X/c
Output relay
Alarm indicator
BZ
X
Buzzer
CT1
CT2
Current voltage
converter
Smoothing
circuit
Smoothing
circuit
Current voltage
converter
Gate circuit
ComparatorComparator
Setting circuit
Output circuit
Reference voltage
generator
Power circuit
2. The current flowing into the gate circuit (between G+ and G−) is as follows:
Approximately 1.4 mA at 5 VDC
Approximately 3.4 mA at 12 VDC
Approximately 6.7 mA at 24 VDC
3. When using a K2CU which has the model number suffix "GS" (a model that incorporates gate
input terminals), the control output of the temperature controller must be a voltage output type.
+
−
K2CU
4
K2CU-F Series
When power is supplied to the heater (when the contactor is ON), a
current flows through the wires to the heater elements. At the same
time, a voltage is imposed on the power circuit of the K2CU-F.
The current flowing to the heater wires is detected by the detector
sections through each Current Transformer (CT) incorporated by the
K2CU-F.
The current signals transmitted by the two CTs are sent to the cur-
rent-voltage converters, smoothing circuits, and comparators as
shown in the diagram.
The signal generated by the reference voltage generator is sent to
the setting circuit to provide a reference value. The reference value is
sent to the comparators. Each comparator compares its heater ele-
ment current input and the reference value. If the input is lower than
the reference value, a signal is sent to the output circuit.
There are two detector sections operating independently. If either of
the input signals from the CTs is lower than the reference value, the
output relay and alarm indicator will be activated.
The K2CU-F incorporates a voltage fluctuation compensation func-
tion which automatically corrects the reference value if the supply
voltage fluctuates.
K2CU-P Series
The K2CU-P operates basically in the same way as the K2CU-F.
The comparator compares external current signals and the reference
value and outputs the result of the comparison to the output circuit.
Note: The dotted lines indicate the line conductors passing through the windows of the current transformers.
S1S2
b1
a1
CM
1
X/c
BZ
X
CT
1
CT
2
Contactor
Heater elements
Power supply
To each circuit
Output relay
Alarm indicator
Buzzer
Current voltage
converter
Smoothing
circuit
Smoothing
circuit
Current voltage
converter
ComparatorComparator
Setting circuit
Output circuit
Reference voltage
generator
Power circuit
X/c
BZ
1
678
5
4
3
2
X
CT
200/220 V100/110 V0 V
Contactor
Heater elements
Power supply
To each circuit
Output relay
Alarm indicator
Buzzer
Current voltage
converter
Smoothing
circuit
Comparator
Setting circuit
Output circuit
Reference voltage
generator
Power circuit
Note: The heater and the operating power supply
connected via terminals 6 and 8 or terminals
7 and 8 must be turned ON at the same time.
K2CU
5
■Setting of Operating Current
Use the potentiometer on the front panel to set the operating current.
Rotate the knob to set the desired current value at which the Heater
Burnout Detector should operate. Do not exceed the maximum and
minimum positions.
The K2CU-F’s scale is divided into 12 graduations including sub-
graduations and the K2CU-P’s scale is divided into 5 graduations.
The knobs of the K2CU-F and K2CU-P as shown in the illustrations
are set to 32 A and 0.7 A respectively.
The set operating current is defined as the mean value of the heater
current under normal operating conditions and the heater current
under a burnout or abnormal condition.
■Heater Connection and Current
The following table shows the different connections possible. The formula under each illustration indicates the electrical current value of the heater
elements under normal and abnormal conditions.
Note: Values in this table are correct when a 200 VAC, 1 kW heater is used on a single-phase or three-phase current.
Set value = Normal current + abnormal current
2
Red point
(indicates the set value)
Knob
HEATER FAULT DETECTOR
ALARM 7
6
5
4
8
9
10
K2CU-F40A-C
A4
S1
S2
×
MADE IN JAPAN
OMRON Corporation
0.5
100/200 VAC
50/60Hz
SOURCE
CURRINT 5A/AC/Max.
A
×
10
12
14 16
18
20
K2CU-P1A-A
HEATER FAULT DETECTOR
ALARM
100/200VAC
Phase Normal condition Abnormal condition
Single phase
Three phase Delta network
Star network
V network
200 V
5 A
5 A
1 kW
200 V
0 A
0 A
7.5 A
7.5 A
(5 A × × )
2
√3√3
5 A
5 A
8.7 A
(5 A × × )
1
√
3
√
3
200 V
200 V
1 kW
1 kW
1 kW
2.9 A
2.9 A
2.9 A
200 V
(5 A × )
1
√
3
2.5 A
2.5 A
(5 A × × )
1
2
√
3
√
3
2.5 A
2.5 A
(5 A × × )
1
2
√
3
√
3
200 V
200 V
1 kW
1 kW
5 A
8.7 A
5 A
200 V
(5 A × = 8.7 A)
√
3
2.5 A
2.5 A
(5 A × )
1
2
(5 A × 1)
5 A
5 A
K2CU
6
■Operation Check
K2CU-F@@A-@GS
The operation of the heater burnout detector can be easily checked as follows:
In a Single-phase Circuit
Set the operating current to be 0.6 to 0.55 times the heater current.
Close the SW2 with switch SW
1 turned on. Confirm that the alarm
indicator remains off.
Turn off SW1 and confirm that the alarm indicator comes on, and that
the output relay operates.
In a Three-phase, Delta Network
Set the operating current to be 0.6 times the heater current.
Close the SW3 with switches SW1 and SW2 turned on. Confirm that
the alarm indicator remains off.
Turn off SW2 and confirm that the alarm indicator comes on, and that
the output relay operates.
Turn on SW1 set the operating current to be 0.9 times the heater cur-
rent, and confirm that the alarm indicator goes off and the output
relay releases.
Turn off SW1 and confirm that the alarm indicator comes on, and that
the output relay operates.
In a Three-phase, Star Network
Set the operating current to be 0.9 times the heater current.
Close the SW2 with switch SW
1 turned on. Confirm that the alarm
indicator remains off.
Turn off SW1 and confirm that the alarm indicator comes on, and that
the output relay operates.
Heater
K2CU-F
SSR
SW1
SW2
S
1
S
2
Heater
K2CU-F
S
1
S
2
SW
3
SSR
SW
2
SW
1
K2CU-F
S
1
S
2
SW
2
SSR
SW
1
Heater
K2CU
7
In a Three-phase, V Network 1
Set the operating current to be 0.3 to 0.35 times the heater current.
Close the SW2 with switch SW
1 turned on. Confirm that the alarm
indicator remains off.
Turn off SW1 and confirm that the alarm indicator comes on, and that
the output relay operates.
In a Three-phase, V Network 2
Set the operating current to be 0.6 times the heater current (of the
phase connected between terminals 1 and 2, or the one passed
through the window of the window-type Current Transformer of the
heater burnout detector).
Close the SW2 with switch SW1 turned on. Confirm that the alarm
indicator remains off.
Turn off SW1 and confirm that the alarm indicator comes on, and that
the output relay operates.
K2CU-F, K2CU-P
The operation of the heater burnout detector can be easily checked as follows:
In a Single-phase Circuit
Set the operating current to be 0.55 to 0.6 times the heater current.
Close the contactor with switch SW1 turned on. Confirm that the
alarm indicator remains off.
Turn off SW1 and confirm that the alarm indicator comes on, and that
the output relay operates.
Heater
K2CU-F
S
1
S
2
SW2
SSR
SW1
K2CU-F
S
1
S
2
SW2
SSR
SW1
Heater
Heater
Contactor
Heater
Contactor
K2CU-F
SW
1
S
1
S
2
K2CU-P
SW
1
1
8
6
2
K2CU
8
In a Three-phase, Delta Network
Set the operating current to be 0.6 times the heater current.
Close the contactor with switches SW1 and SW2 turned on. Confirm
that the alarm indicator remains off.
Turn off SW2 and confirm that the alarm indicator comes on, and that
the output relay operates.
Turn on SW1 set the operating current to be 0.9 times the heater cur-
rent, and confirm that the alarm indicator goes off and the output
relay releases.
Turn off SW1 and confirm that the alarm indicator comes on, and that
the output relay operates.
In a Three-phase, Star Network
Set the operating current to be 0.9 times the heater current.
Close the contactor with switch SW1 turned on. Confirm that the
alarm indicator remains off.
Turn off SW1 and confirm that the alarm indicator comes on, and that
the output relay operates.
In a Three-phase, V Network 1
Set the operating current to be 0.3 to 0.35 times the heater current.
Close the contactor with switch SW1 turned on. Confirm that the
alarm indicator remains off.
Turn off SW1 and confirm that the alarm indicator comes on, and that
the output relay operates.
In a Three-phase, V Network 2
Set the operating current to be 0.6 times the heater current (of the
phase connected between terminals 1 and 2, or the one passed
through the window of the window-type Current Transformer of the
heater burnout detector).
Close the contactor with switch SW1 turned on. Confirm that the
alarm indicator remains off.
Turn off SW1 and confirm that the alarm indicator comes on, and that
the output relay operates.
Heater
Contactor
SW1
SW2
K2CU-F
S
1
S
2
Heater
Contactor
K2CU-F
S
1
S
2
SW
1
Heater
Contactor
K2CU-F
S
1
S
2
SW1
Contactor
Heater
K2CU-P
SW
1
1
2
8
6
K2CU-F
S
1
S
2
SW
1
Heater
Contactor
K2CU-P K2CU-F
K2CU
9
■Test Circuit
To check the operation in detail, use the following circuit.
Dimensions
Note: All units are in millimeters unless otherwise indicated.
Slidac
Switch
Slidac
Switch
The dotted lines indicate the line con-
ductor passing through the round
window of the current transformer.
Note: Determine the value of R according to the specifications
of the K2CU to be used. The dotted line indicates the
connection at a supply voltage of 100 or 110 VAC.
2
1
8
7
3
4
5
6
K2CU-P
R
S
1
S
2
CM1
a
1
b
1
K2CU-F
R
K2CU-F K2CU-P
K2CU-F Eight, M3.5
terminal
screwsTwo, 20-dia.
holes
6-dia. mounting
hole
Alarm
indicator
Potentiometer
knob
6
(90)102111
60
108
95
20
33
102
Mounting Holes
6.5 mm max.
6.5 mm max.
Two, 6-dia. or M5
mounting holes
Note: 1. Install the K2CU-F on
a flat surface.
2. When solderless terminal
lugs are desired, use
ones having an outer
diameter of 6.5 mm
maximum.
K2CU-P
Connecting Socket
3.5
5
60
7291
78.5
89
8PFA1 (order separately)
K2CU-P
108
K2CU
10
Installation
■External Connections
K2CU-F@@A-@GS
Single-phase Heater Three-phase Heater
K2CU-F
Single-phase Heater Three-phase Heater
Note: 1. The dotted lines which pass through the heater burnout detector indicate the line conductor passing through the round “window” of the
window-type Current Transformer.
2. Y: External relay for self-holding circuit
BZ: Alarm buzzer
L: Alarm indicator
3. To use a 100 (110) VAC control power supply with K2CU-P, connect it to terminal 7 instead of 6.
Temperature
sensor
Heater
Temperature
controller
Power
supply
Control
voltage
SSR
Y/a
LY
K2CU-F
S
1
CM1
S
2
a1
b1
BZ
Heater
Temperature
controller
Power
supply
Control
voltage
Temperature
sensor
SSR
Y/a
LY
K2CU-F
S
1
CM1
S
2
a1
b1
BZ
Heater
Power
supply
Contactor
Temperature
sensor
Tempera-
ture
controller
Control
contact
Y/a
LY
K2CU-F
S
1
CM1
S
2
a1
b1
BZ
Heater
Power
supply
Contactor
Temperature
sensor
Tempera-
ture
controller Control
contact
Y/a
LY
K2CU-F
S
1
CM1
S
2
a1
b1
BZ
K2CU
11
Three-phase, V-connected Heater
Note: The dotted lines which pass through the heater burnout detec-
tor indicate the line conductor passing through the round “win-
dow” of the window-type Current Transformer.
With External Current Transformer
K2CU-P Small-capacity, Plug-in Models
Small-capacity Heater With External Current Transformer
Note: 1. The dotted lines which pass through the heater burnout detector indicate the line conductor passing through the round “window” of the
window-type Current Transformer.
2. Y: External relay for self-holding circuit
BZ: Alarm buzzer
L: Alarm indicator
3. To use a 100 (110) VAC control power supply with K2CU-P, connect it to terminal 7 instead of 6.
Heater
K2CU-F
S
1
CM1
S
2
a1
b1
Heater
Power
supply
Note: Pass two out of the three line conductors
through the current transformers of the
heater burnout detector twice as shown.
K2CU-F10A-@
S
1
CM1
S
2
a1
b1
CT
CT
@A/5A
@A/5A
Temperature
sensor
Heater
Temperature
controller
Power
supply
Control
contact
K2CU-P
1
8
7
2
4
5
6
3Y/a
LY
BZ
Temperature
sensor
Heater
Power
supply
Control
contact
Contactor
CT
@A/5A
Y/a
LY
K2CU-P
1
8
7
2
4
5
6
3
BZ
Tempera-
ture
controller
K2CU
12
Safety Precautions
K2CU-F@@A-@GS
Use the K2CU-F@@A-@GS (with gate input terminals) in combina-
tion with a temperature controller that has PID with feed-forward cir-
cuitry to control the heater temperature, in which case, the heater
element(s) must be turned ON or OFF for 0.1 s or longer.
K2CU-F
When a single-phase heater is used, pass the two lines through the
openings of the heater burnout detector. When a three-phase heater
is used, pass two (phases) of the three lines through the openings. In
either case, if only one line passes through, an alarm signal will
always be produced.
Pass the lines through the openings only once. If they are passed
more than once, the actual operating current will be less than the set
current. The lines can be passed in either direction.
To use the heater burnout detector at a current less than the current
range that can be set, the lines must be passed more than once.
Determine the number of times the lines should be passed by the fol-
lowing equation:
(Operating current) x n = Current setting range
where,
n: number of times the lines loop through the window
All K2CU-F models incorporate a voltage fluctuation compensation
function.
K2CU-P
The K2CU-P can be used only in single-phase circuits.
Do not pull out the K2CU-P from the socket when the K2CU-P is
energized. Especially when using it in combination with a Current
Transformer commercially available, this practice causes the second-
ary circuit of the transformer to open, which is very dangerous.
General
Refer to External Connections before using the K2CU with external
CTs.
When a temperature controller is used in combination with the K2CU
(except for the K2CU-F@@A-@GS), the heater element(s) must be
turned ON or OFF for 1 s or longer (although the heater element(s)
can be turned ON for 0.5 s according to the specifications).
The K2CU cannot be used with a phase-control circuit, inverter cir-
cuit, frequency-count circuit, cycle-control unit, or a motor load.
Mounting
Securely mount the K2CU as horizontally as possible although there
is no particular limitation of mounting directions.
Connection
Solderless-type terminal must be connected to the terminals
securely.
Wire the terminals correctly by referring to the external connections.
The terminals have no polarity. Be sure to connect 100 (or 110) V to
the 100-V (or 110-V) terminals and 200 (or 220) V to the 200-V (or
220-V) terminals of the K2CU-P or the K2CU-P may malfunction.
The control power source for the K2CU (except for the K2CU-F@@A-
@GS) must be supplied from the load side via a contactor.
Be sure to impose a voltage between the 0-V terminal and 100-V (or
110-V) terminal or the 0-V terminal and 200-V (or 220-V) terminal of
the K2CU-P, otherwise the K2CU-P will not operate.
With single-phase
power supply
With three-phase
power supply
Heater
Heater
K2CU
13
What settings are required to connect more than one heater in parallel?
The following table shows relative changes in the current when any one of several elements connected in parallel has burned out. Use this
table as a guideline in determining the current setting. The degree of change in the current when an element burns out may be too small
to detect if more than five elements are connected in parallel. As a rule, do not connect more than 5 elements in parallel.
Note: 1. This table shows the respective change rates in current when any one of several elements connected in parallel has burned out.
2. The values in the table are current ratios after one element burns out in comparison to a normal current of “1” (i.e., the current before the
element burns out).
3. The values in this table are logical values. These values may vary slightly because of influence of unbalanced loads (heaters). It is there-
fore recommended to test the actual current values and the load condition before determining the operating current, especially when the
current under the normal condition and that under an abnormal condition do not significantly differ.
Can the K2CU be used for heaters with a voltage of 400/
440?
Yes. It can be used if a power transformer is used to drop the
voltage applied to the control power supply voltage terminals
of the K2CU to 100 to 220 V.
Can the K2CU be used for three-phase circuits with
unbalanced currents?
Unbalanced currents can exist because of different heater
capacities or because different numbers of elements are
connected to each phase, causing the current for each phase
to be different even during normal operation.
There is only one setting provided for the two holes on the
K2CU, so the setting must be made below the current value
for the phase with the lowest current. This could prevent the
current from dropping below the set value depending on the
element that burns out. It is thus not possible to detect heater
burnouts for all elements connected with unbalanced
currents. Either balanced circuits must be used, or a separate
K2CU must be installed for each phase.
Can the control power supply for the K2CU be connected
from a separate circuit from the one used for the heater
circuit?
With a model with a large-capacity, built-in current
transformer, changes in the control power supply voltage are
used in compensating the reference value for the internal
setting circuit. A large error may occur in the operating value
if power is supplied from a separate circuit.
Connection n = 1 n = 2 n = 3 n = 4 n = 5
Single-
phase
I is 0 when one
element burns
out
0.5 0.67 0.75 0.8
Star Current in burned-out phase I is 0 when one
element burns
out
0.6 0.75 0.82 0.86
Current in other phases 0.87 0.92 0.95 0.96 0.97
Delta Current in burned-out phase 0.58 0.77 0.84 0.88 0.91
Current in other phases 1 1 1 1 1
Q&A
Q
INo. of heater = n
No. of heater
per phase = n
I
No. of heater
per phase = n
I
Q
Q
Q
In the interest of product improvement, specifications are subject to change without notice.
ALL DIMENSIONS SHOWN ARE IN MILLIMETERS.
To convert millimeters into inches, multiply by 0.03937. To convert grams into ounces, multiply by 0.03527.
Terms and Conditions Agreement
Read and understand this catalog.
Please read and understand this catalog before purchasing the products. Please consult your OMRON representative if you
have any questions or comments.
Warranties.
(a) Exclusive Warranty. Omron’s exclusive warranty is that the Products will be free from defects in materials and workmanship
for a period of twelve months from the date of sale by Omron (or such other period expressed in writing by Omron). Omron
disclaims all other warranties, express or implied.
(b) Limitations. OMRON MAKES NO WARRANTY OR REPRESENTATION, EXPRESS OR IMPLIED, ABOUT
NON-INFRINGEMENT, MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE OF THE PRODUCTS. BUYER
ACKNOWLEDGES THAT IT ALONE HAS DETERMINED THAT THE
PRODUCTS WILL SUITABLY MEET THE REQUIREMENTS OF THEIR INTENDED USE.
Omron further disclaims all warranties and responsibility of any type for claims or expenses based on infringement by the
Products or otherwise of any intellectual property right. (c) Buyer Remedy. Omron’s sole obligation hereunder shall be, at
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equal to the purchase price of the non-complying Product; provided that in no event shall Omron be responsible for warranty,
repair, indemnity or any other claims or expenses regarding the Products unless Omron’s analysis confirms that the Products
were properly handled, stored, installed and maintained and not subject to contamination, abuse, misuse or inappropriate
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not be liable for the suitability or unsuitability or the results from the use of Products in combination with any electrical or
electronic components, circuits, system assemblies or any other materials or substances or environments. Any advice,
recommendations or information given orally or in writing, are not to be construed as an amendment or addition to the above
warranty.
See http://www.omron.com/global/ or contact your Omron representative for published information.
Limitation on Liability; Etc.
OMRON COMPANIES SHALL NOT BE LIABLE FOR SPECIAL, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL DAMAGES,
LOSS OF PROFITS OR PRODUCTION OR COMMERCIAL LOSS IN ANY WAY CONNECTED WITH THE PRODUCTS,
WHETHER SUCH CLAIM IS BASED IN CONTRACT, WARRANTY, NEGLIGENCE OR STRICT LIABILITY.
Further, in no event shall liability of Omron Companies exceed the individual price of the Product on which liability is asserted.
Suitability of Use.
Omron Companies shall not be responsible for conformity with any standards, codes or regulations which apply to the
combination of the Product in the Buyer’s application or use of the Product. At Buyer’s request, Omron will provide applicable
third party certification documents identifying ratings and limitations of use which apply to the Product. This information by itself
is not sufficient for a complete determination of the suitability of the Product in combination with the end product, machine,
system, or other application or use. Buyer shall be solely responsible for determining appropriateness of the particular Product
with respect to Buyer’s application, product or system. Buyer shall take application responsibility in all cases.
NEVER USE THE PRODUCT FOR AN APPLICATION INVOLVING SERIOUS RISK TO LIFE OR PROPERTY OR IN LARGE
QUANTITIES WITHOUT ENSURING THAT THE SYSTEM AS A WHOLE HAS BEEN DESIGNED TO ADDRESS THE RISKS,
AND THAT THE OMRON PRODUCT(S) IS PROPERLY RATED AND INSTALLED FOR THE INTENDED USE WITHIN THE
OVERALL EQUIPMENT OR SYSTEM.
Programmable Products.
Omron Companies shall not be responsible for the user’s programming of a programmable Product, or any consequence
thereof.
Performance Data.
Data presented in Omron Company websites, catalogs and other materials is provided as a guide for the user in determining
suitability and does not constitute a warranty. It may represent the result of Omron’s test conditions, and the user must correlate
it to actual application requirements. Actual performance is subject to the Omron’s Warranty and Limitations of Liability.
Change in Specifications.
Product specifications and accessories may be changed at any time based on improvements and other reasons. It is our
practice to change part numbers when published ratings or features are changed, or when significant construction changes are
made. However, some specifications of the Product may be changed without any notice. When in doubt, special part numbers
may be assigned to fix or establish key specifications for your application. Please consult with your Omron’s representative at
any time to confirm actual specifications of purchased Product.
Errors and Omissions.
Information presented by Omron Companies has been checked and is believed to be accurate; however, no responsibility is
assumed for clerical, typographical or proofreading errors or omissions.
2015.10
In the interest of product improvement, specifications are subject to change without notice.
OMRON Corporation
Industrial Automation Company
http://www.ia.omron.com/
(c)Copyright OMRON Corporation 2015 All Right Reserved.