Ground Fault Relays RCD300M2 Differential Current Relay Features/Benefits ƒ Adjustable sensitivity of 10 mA to 3.0 A reduces nuisance trips. ƒ Adjustable time delay of 0-1.5 sec adapts to unique applications. ƒ Metering output with PLC interface for ease of continuous monitoring of system. ƒ Transformer continuity test allows immediate assurance of a safe system The RCD300M2 residual current relay is designed to provide sensitive ground fault ƒ C.T. Loop Monitoring protection without the problems associated with high-sensitivity nuisance tripping. It operates ƒ Harmonic Filtering continuously and has the unique feature of a metering output to drive either a remote meter or ƒ DIN Standard molded case for interface with a PLC. This output signal gives ease of mounting via snap on rail the RCD300M2 both protective and predictive or screw mounting. capabilities. By using it, leakages can be seen as they occur and ground faults can be detected before they become critical. Applications The RCD300M2 operates in conjunction with a Ground fault relays can be used for the protection of Littelfuse WKE Series current transformer. The critical circuits in applications such as panel boards combination of the RCD300M2 measuring signal and switch boards, OEM power distribution panels and the output signal from the WKE provide the and custom controls. Additional applications include required resilience to electrical noise - the main electric vehicle charging systems, wastewater cause of nuisance tripping. treatment plants, marinas, pools and spas. The RCD300M2 can operate on grounded, high- resistance grounded and ungrounded power Maintenance systems. When a ground fault occurs, the RCD300M2 operates the leakage current output The RCD300M2 requires no special maintenance relay after the preset time delay. The procedures. Regular operation of the test features at RCD300M2 also continuously checks the suitable intervals and cleaning of the external parts connection to the C.T. If the C.T. circuit is are sufficient. broken, the RCD300M2 indicates "C.T. Fault" and operates the output relay. Due to its sensitivity, the RCD300M2 provides a high degree of network protection and personnel safety as well as minimizing the risk of fire. Littelfuse, Inc. POWR-GARD Products 1-800-TEC-FUSE | www.littelfuse.com 800 E. Northwest Highway, Des Plaines, IL 60016 Ground Fault Relays Pure ac and pulsed ac/dc Systems Transformer Continuity Test The RCD300M2 will work on both ac and pulsed The RCD300M2 continuously monitors the connection ac/dc systems detecting even dc ground faults on the to the CT. If this loop is broken the output relay is load side of the rectifier. operated and the “C.T. FAULT” LED provides immediate indication of the front panel. The test Construction button S1 is used to electronically interrupt this cycle The RCD300M2 comes in a DIN standard molded as a means of testing the function. case suitable for snap-on rail mounting or for screw A remote test button S5 (single pole, normally- open mounting. spring return) may also be installed in series with the external C.T. wiring. Operation The RCD300M2 operates with a range of current Time Delay Adjustment transformers which come in diameters ranging from 1” The RCD300M2 time response is continuously to 81/4”. The output relay and the alarm indicator on adjustable from 0-1.5 seconds by a potentiometer on the front cover are adjustable internally for hand or the front plate. automatic reset. In the hand reset mode, a remote reset button may be used. Trip/Alarm Output Relay Two sets of changeover trip/alarm contacts are The test facility on the RCD300M2 may be actuated provided, rated at 250V, 5A. This allows one set to locally or remotely. It electronically tests both the be used for tripping and the other set for remote current transformer loop continuity and the output indication. relay operation. Under FAILSAFE operating conditions, the relay coil Mounting and Wiring is energized with Terminals 12-13 and 14-15 closed The RCD300M2 can be either DIN rail mounted or (FAlLSAFE MODE). The action may be reversed fixed to a panel using 2 screw holes at the device (ACTIVE MODE) by adjusting switch S3 located corners. Terminals are clearly marked for connection. behind the front plate. In the ACTIVE mode the relay coil is energized only when a group fault occurs. Switch S3: CLOSED = ACTIVE OPEN = FAILSAFE Metering Output The RCD300M2 has a continuous metering output to drive either a remote meter or interface with a PLC. The output signal is 0 – 1mA and is proportional to 0 – 100% of the relay trip response rating. Leakage Current Response Adjustment Leakage current response adjustment has a 10 position fixed point selector switch adjustable from 10mA to 3.0 Amps Local Alarms In addition to the trip relay there are 3 LED indicators on the front cover. The green LED is for “POWER ON”, the upper red LED indicates “LEAKAGE CURRENT” and the lower red LED indicates a C.T. Auxiliary Supply FAULT The RCD300M2 requires an auxiliary supply voltage of 24V ac/dc or 120V, 50/60 Hz. The unit can also be ordered to operate with other power supplies. Littelfuse, Inc. POWR-GARD Products 1-800-TEC-FUSE | www.littelfuse.com 800 E. Northwest Highway, Des Plaines, IL 60016 Ground Fault Relays Specifications Wiring Diagrams Nominal AC insulation Voltage 500 V AC Insulation Ground t UL 508 Class C VDE 0110 Test voltage 2000 V AC Operation Class Continuous Supply voltage Vs 24V ac/dc or 120V, 50-60 Hz Maximum self consumption 4VA Alarm Relay Contacts 2 volt-free NO/NC Switching capacity 1100VA Rated Contact voltage 250V Continuous Current 5 A Breaking Capacity @240V AC P.F. = 0.4 3 A @ 110VDC, @L/R = 0 0.3 A Relay Function Selection Adjustable Function Failsafe/Active Relay Alarm Memory Hand/Auto Reset Factory Settings Auto Reset Leakage Current Response 10/30/60/80/100/ Range 300/600/800mA, 1.0/3.0A Time Delay 0 - 1.5 secs H1 LED green “POWER ON” Operating Ambient Temp. -10 to +60 deg. C H2 LED red “LEAKAGE CURRENT” Storage Ambient Temp. -40 to +80 deg. C H3 LED red “C.T. FAULT” S1 TEST button Mounting S2 RESET button Terminal Capacity 0.5 to 5 mm⒉ S3 FAILSAFE/ACTIVE Weight .73 lbs Located behind front plate “Closed” = Active “OPEN” = Failsafe CT Type WKE 1” to 8.25” dia. S4 Leakage current selector switch (see Chart) K1 Relay for alarm R Time delay potentiometer S5 External test button (optional) S6 External reset button (optional) WKE Series Current Transformer I External meter for leakage current There are 7 diameters of C.T.s ranging from 1” to 1-2 Input power supply 24V ac/dc or 8 ¼ “. The C.T. is connected across terminals 7 and 120VAC 8. It is essential when installing C.T.s that only the 7-8 C.T connections load cable conductors L and N (1PH) or L1, L2, and L3 5-6 Auto/Hand reset selections with N, if used (3ph, 3 or 4 wire), are passed through the center of the C,T. The ground wire must remain outside the C.T, core. Part Number Internal Diameter WKE 25* 1” WKE 35 1 3/8” WKE 60* 2 1/3” WKE 95* 3 ¾” WKE 130* 5 1/8” WKE 200* 8” WKE 210 8 ¼” * High Current Applications Littelfuse, Inc. POWR-GARD Products 1-800-TEC-FUSE | www.littelfuse.com 800 E. Northwest Highway, Des Plaines, IL 60016 Ground Fault Relays WKE Series Current Transformers Primary Current 2500A Secondary Current 350mA The WKE Series of current transformers is a NSV 600Vac key component of the POWR-GARD ground BIL Rating 2000V fault detection product line. These CTs are Rated Frequency 10 – 1000Hz highly accurate. They convert very small Thermal current rating 70˚ C differential currents to an ac voltage and output this signal to the connected POWR-GARD No Fixed Burden Accuracy 99% ground fault relay. The WKE Series CTs are made from high-density mu metal which has Flux Shielding unique and repeatable output characteristics. Installation Instructions Features When installing the WKE CTs, ensure the The WKE CTs have built-in safety features far following: surpassing those of CTs with a ferrite core. 1. Only the load carrying conductors pass The WKE CT is resistant to open circuit burn through the center of the CT. (This out and will saturate at safe, low-level voltages. means L1 + N for 1 phase and L1+ L2 + The CTs are housed with an insulating L3 for 3 phases.) protection. They have built in brackets to 2. The power conductors pass through the facilitate mounting. Terminal cover may be center of the CT and are preferably wire sealed for further protection bound together to keep the conductors uniformly spaced. 3. The power conductors pass PERPENDICULAR to the CT and, whenever practical, continue perpendicular to the CT on both sides of the CT for 3”. 4. The power conductors should not be installed in a way that allows them to run along the side edges of the CT. 5. Whenever practical, locate the CT away from noise-generating devices such as transformers, frequency converters, etc. Dimensions (in) a b c d e 1 3 3.9 1.63 3.63 WKE 25 2.36 3.9 5.25 2.37 4.50 WKE 60 3.74 5.5 6.9 3.25 6.25 WKE 95 5.12 7.25 8.5 4 7.0 WKE130 8.0 10.4 12.1 6.0 11.4 WKE 200 Littelfuse, Inc. POWR-GARD Products 1-800-TEC-FUSE | www.littelfuse.com 800 E. Northwest Highway, Des Plaines, IL 60016