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KM50-E

Smart Power Monitor

KM50-E

Power and current can be measured simultaneously. Measurement of generated power (regenerative power), leading reactive power, lagging reactive power, and consumed power. High-performance Power Monitor.

about this Product Family

Ratings

Model KM50-E
Applicable circuit Single-phase two-wire, single-phase three-wire, three-phase three-wire, and
three-phase four-wire power
Rated power supply voltage 100 to 240 VAC, 50/60 Hz
Allowable supply voltage range 85% to 110% of rated power supply voltage
Allowable frequency range 45 to 65 Hz
Power consumption 7 VA max.
Rated
input
Rated input voltage 100 to 480 VAC (single-phase, 2-wire): Line voltage
100/200 VAC (single-phase, 3-wire): Phase voltage/line voltage
100 to 480 VAC (3-phase, 3-wire): Line voltage
58 to 277 VAC (3-phase, 4-wire): Phase voltage
Rated input current 5 A, 50 A, 100 A, 200 A, 400 A, or 600 A (primary current of Special CT) *
Rated frequency 50/60 Hz
Rated input power With 5-A CT: 4 kW
With 50-A CT: 40 kW
With 100-A CT: 80 kW
With 200-A CT: 160 kW
With 400-A CT: 320 kW
With 600-A CT: 480 kW
Allowable input voltage 110% of rated input voltage (continuous)
Allowable input current 120% of rated input current (continuous)
Rated input load Voltage input: 0.5 VA max. (excluding power supply)
Current input: 0.5 VA max. (for each input)
Time 2010 to 2099 (Adjusted for leap year.)
Accuracy: ± 1.5 min/month (at 23 °C)
Time backup period 7 days (without power supply, at 23 °C)
Ambient operating temperature -10 to +55 °C (with no condensation or icing)
Storage temperature -25 to +65 °C (with no condensation or icing)
Ambient operating humidity 25% to 85%
Storage humidity 25% to 85%
Altitude 2,000 m max.
Installation environment Overvoltage category and measurement category: 2, Pollution level: 2

* A special output signal is output as the secondary current from the Special CT.

Performance

Smart Power Monitor

Model KM50-E
Accuracy
*1
Voltage ± 1.0% FS ± 1 digit (at ambient temperature of 23 °C, rated input, and rated
frequency).
However, the accuracy is ± 2.0% FS ± 1 digit for the Vtr line voltage for
three-phase, three-wire power and the Vrs line voltage for single-phase,
three-wire power under the same conditions.
Current ± 1.0% FS ± 1 digit (at ambient temperature of 23 °C, rated input, and rated
frequency).
However, the accuracy is ± 2.0% FS ± 1 digit for the phase-S current for
three-phase, three-wire power and the phase-N current for single-phase,
three-wire power under the same conditions.
Active power Reactive
power
± 2.0% FS ± 1 digit (at ambient temperature of 23 °C, rated input, rated
frequency, and a power factor of 1)
Reactive power formula: Reactive power = v × i × sin θ
* "v" is the instantaneous voltage and "i" is the instantaneous current.
θ is the phase difference between the voltage and current.
Frequency ± 0.3 Hz ± 1 digit (at ambient temperature of 23 °C, rated input, and rated
frequency)
Power factor ± 5.0% FS ± 1 digit (at ambient temperature of 23 °C, rated input, rated
frequency, and power factor = 0.5 to 1 to 0.5)
Power factor formula: Power factor = Active power/Apparent power
* Apparent power = √ (Active power)2 + (Reactive power)2
Temperature ± 5 °C two hours after the power is turned ON (after setting the offset to match
the ambient environment)
Low-cut current set value 0.1% to 19.9% of rated current input (in 0.1% increments)
Sampling cycle 100 ms for measurement voltage at 50 Hz and 83.3 ms for measurement
voltage at 60 Hz
Temperature influence *1 ± 1.0% FS ± 1 digit (percentage of power within operating temperature range,
at ambient temperature of 23 °C, rated input, rated frequency, and power
factor of 1)
Frequency influence *1 ± 1.0% FS ± 1 digit (percentage of power within rated frequency ± 5 Hz, at
ambient temperature of 23 °C, rated input and power factor of 1)
Influence of harmonics *1 ± 0.5% FS ± 1 digit (at ambient temperature of 23 °C, error for superimposed
2nd, 3rd, 5th, 7th, 9th, 11th, and 13th harmonics for a content percentage of 30%
for current and 5% for voltage of the basic wave)
Insulation resistance 1) Between all power circuits and all of the RS-485 terminals, OUT1, OUT2,
event inputs, I/O commons, and transistor outputs: 20 MΩ max. (at 500 VDC)
2) Between all current and voltage inputs and all of the RS-485 terminals,
OUT1, OUT2, event inputs, I/O commons, and transistor outputs: 20 MΩ max.
(at 500 VDC)
3) Between all current and voltage inputs and the front case: 20 MΩ max. (at
500 VDC)
4) Between all power circuits and the front case: 20 MΩ max. (at 500 VDC)
Dielectric strength 1) Between all power circuits and all of the RS-485 terminals, OUT1, OUT2,
event inputs, I/O commons, and transistor outputs: 2,800 VAC for 1 min
2) Between all current and voltage inputs and all of the RS-485 terminals,
OUT1, OUT2, event inputs, I/O commons, and transistor outputs: 3,600 VAC
for 1 min
3) Between all current and voltage inputs and the front case: 3,600 VAC for 1 min
4) Between all power circuits and the front case: 2,800 VAC for 1 min
Vibration resistance Single amplitude: 0.35 mm, Acceleration: 50 m/s2, Frequency: 10 to 15 Hz, 10
sweeps for 8 min each along three axes
Shock resistance 150 m/s2, 3 times each in 6 directions (up/down, left/right, forward/backward)
Weight Approx. 250 g (Power Monitor only)
Degree of protection Front panel: IP66 (when mounted to a panel), Rear case: IP20, Terminal
section: IP00
Memory backup EEPROM (non-volatile memory), No. of writes: 1,000,000 times
Compliant standards EN61010-1 (IEC61010-1), EN61326-1 (IEC61326-1), UL61010-1, CAN/CSA-
C22.2 No.61010-1
Event
inputs
Number of inputs Two event inputs
The two event inputs use the same common terminal
Voltage input High level: 4.75 to 30 VDC
Low level: 0 to 2 VDC
Input impedance: Approx. 2 kΩ
No-voltage input ON resistance: 1 kΩ max.
OFF resistance: 100 kΩ min.
ON residual voltage: 8 V max.
ON current (at 0 Ω ): 10 mA max.
Minimum input time 5 ms
Transistor
outputs
Number of outputs 5 open-collector outputs (two total power consumption pulse output or alarm
output, and three, 3-state outputs)
The total power consumption pulse output and alarm output use the same
common terminal.
The three, 3-state outputs use the same common terminal.
Output capacity 30 VDC, 30 mA max.
ON residual voltage: 12 V max.
OFF leakage current: 100 μ A max.
Alarm output delay *2 OFF delay: 0.0 to 99.9 s, ON delay: 0.0 to 99.9 s
Characteristic
operating time *3
±200 ms
Communi-
cations
Communications
method
RS-485 (2-wire half-duplex)
Sync method Start-stop
Unit number setting CompoWay/F: 0 to 99, Modbus: 1 to 99
Baud rate 1.2, 2.4, 4.8, 9.6, 19.2, 38.4 kbps
Transmission code CompoWay/F: ASCII, Modbus: Binary
Data length 7, 8 bits
Stop bit length 1, 2 bits
Vertical parity Even, odd, or none
Maximum transmission
distance
500 m
Maximum number of
connected Power
Monitors
CompoWay/F: 31, Modbus: 99
EMC
(Industrial electromagnetic
environment)
EMI
EN61326-1
Radiated RF Electromagnetic Field: CISPR 11 class A
Conducted Emission: CISPR 11 class A
EMS
EN61326-1
Electrostatic Discharge Immunity: EN61000-4-2
Electromagnetic Field Immunity: EN61000-4-3
Fast Transient/Burst Noise Immunity: EN61000-4-4
Surge Immunity: EN61000-4-5
Conducted Disturbance Immunity: EN61000-4-6
Power Frequency Magnetic Field Immunity: EN61000-4-8
Voltage Dip and Interruption Immunity: EN61000-4-11

*1 The error of the Special CT is not included.
*2 There may be error in the alarm output OFF delay and ON delay due to the measurement sampling cycle.
*3 This is the error in the operating time of the alarm output (including the error in the alarm output ON/OFF delays and
      output terminal switch operating time).

CTs

Model KM20-
CTF-
5A
KM20-
CTF-
50A
KM20-
CTF-
100A
KM20-
CTF-
200A
KM20-
CTF-
400A
KM20-
CTF-
600A
Rated primary current 5 A 50 A 100 A 200 A 400 A 600 A
Secondary winding 3,000 turns 6,000 turns 9,000 turns
Application frequency 10 Hz to 5 kHz
Insulation resistance Between output terminal and external case: 50 MΩ min. (at 500 VDC)
Dielectric strength Between output terminal and external case: 2,000 VAC for 1 min
Protective element 7.5 V clamp element
Allowable number of
connections/disconnections
100 times
Inner diameter 10 dia. 16 dia. 24 dia. 37 dia.
Operating temperature and
humidity range
- 20 to + 60 °C 85% (with no condensation)
Storage temperature and
humidity range
- 30 to + 65 °C 85% (with no condensation)

* If you use a flat cable, select the cable based on the dimensions of the CT.

CT Cable

Model KM20-CTF-CB3
Cable length 3 m

Note: Either use the CT Cable specified by OMRON or use 1.25-B3A crimp terminals and AWG22 wire from J.S.T. Mfg.
          Co., Ltd.