To order, specify : Types Protection functions Current surge Asymmetry and loss of phase. Operating principle

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1 otor protection relays - T - FWIT Since % of -phase motor failures are due to load problems or loss of phase, the CROUZET range of motor protection relays is indispensable! models give motor protection over a range of to 60 (. kw to kw). current transformer is not required between and.7. bove this, a CT/ can be used up to 60. FWIT Operating principle Current surge The output relay trips when there is a current surge which is at least 0% higher than the nominal motor current. The control relay adjusts its trip time depending on whether the motor is warm or cold. symmetry and phase fault When the asymmetry between the different phase currents is greater than 0%, and when there is a phase fault, the relay trips after a time delay which depends on the fault conditions, whatever the motor load (including no-load). Overtemperature The relay trips immediately if the PTC probe in the motor reaches the reaction value. Phase sequence In the case of phase inversion, the relay trips in less than 00ms. Types Protection functions Current surge symmetry and loss of phase Overtemperature Phase order Part numbers (and voltages) 0 V T FWIT Characteristics Types T FWIT otor nominal current setting range (IB) Supply voltage - 0 V - 0 V - 0 V Frequency /60 Hz /60 Hz /60 Hz Via -phase motor Kw Hp Cold trip time - 0s - 0s - 0s at 6 x IB Contact output O O O C C C ax. power consumption V V V O contact V C V C V C C contact V C V C V C Contact electrical life (number of operations) Contact mechanical life (number of operations) aximum conductor cross-section.mm.mm.mm ax. terminal tightening torque.cm.cm.cm Temperature Use - c +60 c - c +60 c - c +60 c Stored -0 c +70 c -0 c +70 c -0 c +70 c Weight 0.kg 0.kg 0.kg Degree of protection : Terminals IP IP IP Device IP0 IP0 IP0 PTC probes ax. cold resistance 0Ω in. cold resistance Ω Tripping resistance 000Ω CE marking To protect output contacts against short-circuits, use a 0 miniature circuit-breaker Conforming to low voltage and electromagnetic compatibility directives Other information For connections, see page /8 For conformity, common characteristics, see page / For dimensions, see page / Standard products To order, specify : Part number Example : otor protection relays /0

2 Technical user guide The, T and FWIT relays are designed solely to protect - phase motors. The basic model has functions for protecting against current surge as well as protecting against asymmetry and phase faults. The T model possesses an additional thermal protection function via PTC probe. The FWIT model is the most complete in the range, integrating a protection function against phase inversion. L - T - FWIT L L Display Indication of trip caused by phase inversion Indication of trip caused by overtemperature Indication of trips caused by asymmetry or loss of phase Indication of overloads (flashing), or disconnection due to overload (steady light) Thermal relay on/off indication -position micro-switch for adjusting the trip time to 6xIB. Instantaneous overload test from.0xib icroswitch 8 positions for adjusting the motor nominal current Reset button K PTC connection terminals. If this protection is not used, T and T must be shortcircuited, otherwise the relay trips and it is impossible to reset. The relay is supplied with a strap on T and T Contact connection terminals : O (97-98) - C (9-96) Supply voltage connection terminals Phase fault test button Output relay and state indication (O) Relay on not tripped O (97-98) Closed C (9-96) Open Relay tripped by symmetrical current surge +t Relay tripped by asymmetry or loss of phase Relay tripped by overtemperature Relay tripped by phase inversion a Relay not tripped but in current surge state Imotor >.0 x IB O (97-98) Closed C (9-96) Open If before the end of the time delay Imotor <.0 x IB, the state changes to "Relay on not tripped". Otherwise, the state changes to "Relay tripped by symmetrical current surge". /7

3 Technical user guide Reset When the relay is tripped, it must be reset in order to return to the previous state. There are two reset options : anual reset by pressing the RESET button. Remote reset by cutting the relay power supply for at least seconds. Test function - T - FWIT phase loss fault can be simulated by pressing the TEST button for seconds, with the motor running. Setting the nominal current (IB) The nominal motor current (IB) is set via 8 microswitches. Each microswitch enables a value to be added to the base value defined for each relay. By pressing the microswitch, the rated value for this microswitch is added to the base value. The maximum value that can be set for each type of relay is : Base values 8 T FWIT =.7 for the.7 = 7.7 for the T 7.7 = 9.7 for the FWIT When the nominal motor current is not known Using the current surge indication : Led flashing. When all microswitches have been activated and the motor is at full load, gradually reduce the current setting until the red LED flashes. The LED begins to flash at.0xib, IB can therefore be easily calculated by adding 0 % to the preset value. Examples If the various microswitch combinations do not allow the nominal motor current to be set precisely, the current should be set to the next highest value. Important : The current which should be set on the device is not the trip threshold but the nominal motor current. In the case of Star/Delta starting In all cases, whatever the motor connection, the protection relay must be installed on the line conductors between the contactor and the fuses (see wiring diagram page 6). Using a relay with a star-delta connection is identical to operation with D.O.L. starting. It is not necessary to apply the typical correction factor for the delta connection (0.8 x IB). When the nominal motor current is greater than the maximum relay measurement current In this case, use an external current transformer with standard output at the bottom of the scale : IB = I motor I transformer x x o. of loops When the nominal motor current is less than the minimum relay measurement current To protect motors whose nominal current is less than : 8 for the for the T 7 for the FWIT, loop the motor supply cables several times through the relay orifices : IB = I motor x number of loops. /8

4 Setting the trip time () The trip time is set via microswitches situated on the right of the front face. The time set corresponds to the relay trip time when the motor is cold and the current = 6 x IB. Examples + 6 = 0 S + 6 = 6 S + 6 = 0 S Trip curves When the motor is warm, the trip time decreases considerably. The cold and warm trip curves show the time variation in the various cases of current surge. = + 6 S t6 x I + 6 = S B + 6 = 0 S Recommendation for setting the trip time cold The trip time to be set is linked to the motor starting time. To avoid the relay tripping when the motor starts, the following settings are recommended : T FWIT starting quick (0. -.s) normal (. - s) long ( - 0s) setting s < < 8s 8s < < 6s 6s < < 0s When star-delta starting is used, the time should be modified according to the starting time in star connection (X ) CURVE - =.7 ; t 6 x = 0 CURVE - = 8.0 ; t 6 x = 0 CURVE - =.7 ; t 6 x = CURVE - = 8.7 ; t 6 x = hot (X I ) B CURVE - = 7.7 ; t 6 x = 0 CURVE - =.0 ; t 6 x = 0 CURVE - = 7.7 ; t 6 x = CURVE - =.0 ; t 6 x = (X I ) B CURVE - = 9.7 ; t 6 x = 0 CURVE - = 7.0 ; t 6 x = 0 CURVE - = 9.7 ; t 6 x = 0 CURVE - = 7.0 ; t 6 x = 0 otor star connection starting time (s) Time to set on the relay (t6xib) , (X ) CURVE - =.7 ; t 6 x = 0 CURVE - = 8.0 ; t 6 x = 0 CURVE - =.7 ; t 6 x = CURVE - = 8.7 ; t 6 x = T , (X ) CURVE - = 7.7 ; t 6 x = 0 CURVE - =.0 ; t 6 x = 0 CURVE - = 7.7 ; t 6 x = CURVE - =.0 ; t 6 x = FWIT (X I ) B CURVE - = 9.7 ; t 6 x = 0 CURVE - = 7.0 ; t 6 x = 0 CURVE - = 9.7 ; t 6 x = 0 CURVE - = 7.0 ; t 6 x = 0 /9

5 Wiring diagrams and applications DWR / LWR R S T DPR / LPR () R ST D Y R S T () R T T r > c R Y Y R d U V W ~ S0 S h c c S ~ 6 PTC DI 08 For a 60 Hz supply, short-circuit terminals Y and R ( and ) together. DWR R S T Y LWR 6 7 () - Isolating switch () - Contactor C - Contactor S - O button S0 - OFF button S - Remote reset contact h - Fault indicator DPR T T Y Y LPR T FWIT L L L T T starting T T starting () () K K () contactor CPT PTC a +t D.O.L. starting a +t PTC CPT Connected to transformers with external current /8

6 pprovals and conformity pprovals : UL CS Conforming to : VDE 0 VDE 0609 VDE 00 VBG IEC 8- IEC -0- IEC - & 6 IEC -8 & 7 IEC -- IEC -- IEC - Generic standard for electrical relays Screw terminal connection Creepage distance Protection against accidental contact with terminals Standard covering low voltage control equipment (contactors) - C Generic standard for electrical relays Generic standard for measurement and protection relays Generic standard for measurement and protection relays & thermal protection of motors Protection against HF interference - hz Protection against electrostatic discharges 8 Kv Protection against./ µs impulse voltages and insulation resistance Protection against pulse-string interference Pluggable into -pin base Fitting to DI rail IEC 80- IEC 67.. & 8 DI 677 IEC 9 Class of protection IP 0 unit and IP terminals DI 00 Class of protection IP 0 unit and IP terminals FC 0 Class of protection IP 0 unit and IP terminals Common technical characteristics Self-extinguishing housing Output circuit... Rated power... gcdo changeover 0 V a 90 W c ax. breaking current... 8 ~ 0 c inimum breaking current m a 00 m c ax. breaking voltage V a ominal breaking voltage... V a Electrical life... 0 operations at 0 V resistive echanical life operations Contact/coil isolation... kv /

7 Dimensions CI EI - EUL / EUH - EUS / EUSF, 7, 8 Ø, , 78, 89,7 99, 6,8,7, 7, 8, 00 ET / ET T 7 77, 79, , , 89,7 99, 9 00 Y Y, ,7, TIDR - TD-TDC ccessory 9 8 7, 7 Ø 8 Transformer part number /