One of the common faults faced in industrial plants is over-heating and burning of 3 phase motors due to the phase failure. "Thermicmagnetic device" which is an essential element in motor protection is generally too slow due to both its electro-mechanical structure and the use of high current setting range to assure demarrage without tripping. Being designed to eliminate the above disadvantages, MK-01, MK-01P and MKC-01, MKC-01P Phase Failure Devices react within 0.2 sec. (fixed) against the following faults and take the motor out of service.
1. PTC Protection (Available only in MK-01P and MKC-01P)
When the coil temperature in motors exceeds Tc, the limit temperature of PTC, the output relay switches OFF immediately.
This feature is included MK-01P and MKC-01P. See Fig.1 for typical resistance of PTC vs temperature characteristics for three different switching temperatures (110 0C, 120 0C, 130 0 C) normally, PT-110 is used and it can be changed upon request. See Fig. 1.
2. Voltage Unbalance (Not adjustable)
When the neutral-phase voltage unbalance is greater than 20% (fixed),the output relay is switched off within 0.2 seconds. See Fig.2.
Rated Voltage (Un): 3 Phase and Neutral 230 VAC; 4 Wires, Star Connection
Operating Range: (0.9-1.1) x Un
Rated Frequency: 50/60 Hz.
Output Contacts: 1 C/O with, 5A, 1250 VA, Cosj=1 (for MK-01P, type PK10); 1 C/O with, 8A, 2000 VA, Cosj=1
Warning Led: LED Output : Normally ON (turns OFF on Faults)
Tripping Time: 0.2 s
Ambient Temperature: -5 °C ; +50 °C
Protection Class: IP 20
Dimensions: Type PK 10 (MK-01P); Type PK 21 (MK-01); Type PK 25 (MKC-01 / MKC-01P)
Installation: Surface mounting or on the mounting rails.
Weight: 0.1 kg. (for MK-01 and MKC-01), 0.25 kg. (for MK-01P and MKC-01P)
* : PTC output terminals are available in MK-01P and MKC-01P. If PTC is not used in MK-01P and MKC-01P, by any reason, PTC terminals should be short circuited.
Failure to follow those instructions will result in death or serious injury.
● Disconnect all power before working on equipment.
● When the device is connected to the network, do not remove the front panel.
● Do not try to clean the device with solvent or the like. Only clean the device with a dried cloth.
● Verify correct terminal connections when wiring.
● Electrical equipment should be serviced only by your compedent seller.
● Mount device to the panel.