Entes MKC-06 Phase failure relay MKC-06 MKC-06 Data Sheet

The voltage asymmetry causes the rise in motor temperature and a reduction of the

rated motor power.

Voltage asymmetry limit values can be adjusted between 5%-15% by the user or can

be disabled. Hysteresis is 30% of the adjusted asymmetry value.

Example: Given 3x380 V supply with 10% asymmetry,

Relay switches OFF at: 380-(10x400/100)=340 V

Relay switches ON at: 380-((10-(10x%30))x400/100)=353,2 V

When the phase sequence is correct

(L1, L2, L3 in clockwise direction) the

output relay is activated; however, if

the sequence is changed by any

reason, the output relay switches OFF

immediately. Relay LED is OFF, Phase

Sequence error LED turns ON.

If the value for any of the phases drop

d o w n   t h e   l o s t   p h a s e   l i m i t

value(Unx0.5), Phs.Seq. - Asm. LEDs

turn on simultaneously and the relay

breaks contact wthout delay.

In devices which are supplied from a 3 phase capacitive source(MKC-05/06), the

supply voltage is the mean value of voltages from all three phases. If this mean value

(L3 phase for MKC-05P/06P devices) is less than half the supply voltage, the relay

gives an insufficient supply voltage warning(asm. and Phs. Seq. LEDs flash alternately)

and the relay breaks contact without delay.
MKC-05 and FR-02 with Neutral => (VL1+VL2+VL3)/3 < 115 VAC (P-N)
MKC-05P => VL3< 110 VAC (P-N)
MKC-06 without Neutral => (VL12+VL23+VL31)/3 < 200 VAC (P-P)
MKC-06P => VL31< 190 VAC (P-P)

Phase

Failure

}

Phase Sequence
Fault

One of the common faults encountered in

industrial plants is the overheating and the

resulting damaging of the 3-phase motors

due to the phase failure. “Thermal-magnetic

relay” which is an essential element in motor

protection is generally too slow to assure

demurrage without tripping due to both its

Unbalanced voltage(asymmetry) may occur when;

    The mains are loaded with unbalanced distribution,

    One of the 3 phases of the motor has lost. In this case, some amount of voltage

which is produced by other phases will be induced on the lost phase. Amount of this

voltage depends on both the motor type and amount of load.

    Output relay is making contact when a phase has been lost or an unbalanced Phase-

Phase voltage value, which is occured for any reason, is smaller than the user defined

asymetrical value. If this unbalanced voltage value exceeds the adjusted asymetrical

value(5-15%); output relay will break contact and switch off the motor at the end

of adjusted time delay(0.1-20 sec.); relays LED on the front panel is turned off. Asymmetry

error LED is turned ON. If the fault disappears within the delay time, the output relay

will not break contact and will not switch off the motor.

    In applications; a proper asymetrical value should be adjusted considering the

induced voltage value in two-phase which are remained after the other one has

lost.

electromechanical structure and the use of high current setting range.MKC-05-05P,

MKC-06-06P  and FR-02 Motor Protection Relays which are designed to protect the

desired equipment against phase failure, asymmetry and phase sequence failure on

3 phase systems with or without neutral connection, are manufactured to serve the

following purposes.

By using the asymmetry adjustment knob(%asm.) on the front panel, the upper

asymmetry limit of the system which will be protected is determined. If the unbalance

on the system(asymmetry) exceeds the adjusted value, the device waits as long as

the Delay-OFF time(Delay) and if the unbalance is still over the adjusted value, the

relay of the device breaks contact(OUT LED turns off and Asm. LED turns on). If the

unbalance on the system(asymmetry) falls under the adjusted value, the device waits

as long as the Delay-ON time(Reset Delay) and if the unbalance is still under the

adjusted value, the relay of the device makes contact(OUT LED turns on and Asm.

LED turns off).

Without Neutral

With Neutral

On Out

:Flashing

:LED OFF

:LED ON

Phs. Seq.

Asm.

PTC fault

Phase Fault Warning

Phase Sequence Fault Warning

Unsufficient Supply Warning

3

2

1

Voltage(s) is(are) within adjusted limits

Voltage(s) is(are) out of adjusted limits

Voltage(s) is(are) out of adjusted limits

(Delay time waiting)

W

If motor coil temperature exceeds the

temperature limit of PTC, the motor is

disconnected immediately. The output relay

is opened and Relay LED turns off.

This feature is only available for MKC-05P

and MKC-06P. Resistance-Temperature

values for three PTC with different temperature

limit values (110 

o

C, 120 

o

C, 130 

o

C )

are shown on the figure on the right.

If you want to cancel PTC protection on a

device with PTC protection feature, the PTC

terminals on the device should be short-

circuited.

 (MKC-05/05P/FR-02):
In devices with neutral, Phase-Neutral measurements are taken. If the

neutral cable breaks, the neutral point of the system shifts because of

the asymmetrical phase loading. The device continues the take

measurements according to the shifted neutral system point. MKC-05P

is supplied from Neutral and L3 Phase. Break of neutral cable causes

the device to lose supply and the relay to open.

: 48 ... 63 Hz. MKC-05 / 06, FR-02
: 50/60 Hz. MKC-05P / 06P
: 30 VA / 2 W (50 Hz.)
: True RMS

: 5%...15% (With/Without Neutral) Can be disabled.
: 30% of the adjusted asymmetry value
: 0.1 ... 20 sec.
: 0.1 ... 20 sec.
: ± 3%
: ± 0.5%
: ± 5% + 100 msec.
: ± 3%

: 1 Change-over(CO) Contact, 8A, 250V, 2000VA (Cosj=1)
: 10

5

: 10

7

: -5°C ... +55°C
: <%90 (without condensation)

: 4mm² (12AWG) 

stranded rigid cable

: 6mm² (10AWG) 

solid conductor cable

: 2x2.5mm² (

14AWG

) 

solid conductor cable

: 0.5 Nm (4.5in.lbs)

: 230V AC MKC-05 / 05P, FR-02
: 400V AC MKC-06 / 06P
: 150...300V AC MKC-05 / 05P, FR-02
: 270...510V AC MKC-06 / 06P

: Inside the panel vertically or on to the rail
: Plastic Compliant with UL 94 VO
: IP 20 (Terminals), IP 40 (Front Panel)
: Type PK 28
: 100 gr. Only MKC-05P / 06P 200gr

: 400 V
: Exceeding Voltage Category III,
  Pollution Degree 3
: 4 kV 1.2 / 50 uS
: 2 kV AC 50 Hz. 1  minute.
: >500 MOHM / 500 V DC

: Product Standard
: Immunity
: Emission

LVD
EMC

Vertrieb durch TDE Instruments GmbH