Safety Relays Back EMF Monitors CU3 Specifications Description The CU3 is a control unit which detects stopped motion and is ideal for use with guard locking interlock switches. It is designed to interface with single or three-phase induction motors by measuring the drive voltage and the back electro-magnetic field (emf) of the motor. The front window of the CU3 can be popped off to reveal a replaceable fuse and a potentiometer. The potentiometer sets the threshold voltage measured at terminals Z1/Z2. The maximum threshold voltage is approximately 2.5V peak (potentiometer turned fully CCW). When the voltage at Z1/Z2 exceeds the threshold voltage, the safety outputs de-energize, and the safety contacts at terminals 13/14 and 23/24 open. When the supply to a motor is disconnected, motor speed will reduce to zero. During the run down period the back emf generated by the motor is monitored by the CU3. When the level of the back emf dips below the threshold voltage, the safety outputs close. This enables the output device (e.g., solenoid locking or unlocking switch) to be activated. Standards EN 954-1, ISO 13849-1, IEC/EN 60204-1, IEC 60947-5-1, ANSI B11.19, AS4024.1 Category Cat. 1 per EN 954-1 (ISO13849-1) Approvals C-Tick, CE marked for all applicable directives, cULus & TÜV Power Supply 24V AC/DC or 110/230V AC Power Consumption < 4VA Inputs Z1- Z2 Motor voltage Maximum Motor Voltage 500 V Reset Automatic/manual Outputs 2 N.O. Safety; 1 N.C. Auxiliary ➊ Output Utilization per IEC 60947-5-1 (Inductive) B300 AC-15 5A/250V AC, 5A/125V AC N300 DC-13 3A/24V DC Fuses Power (internal, replace.) Motor Input (external) Output (external) 500mA time lag 500mA quick acting 5A quick acting Max. Switched Current/Voltage 10mA/10V Indication LED Red = Power on Red/Green = Timing/Output on Yellow = Fault Red = Motor running Impulse Withstand Voltage 2500V Operating Temperature -10°C to +55°C (+14°F to +131°F) Humidity 90% RH Enclosure Protection IP40 DIN 0470 Terminal Protection IP20 DIN 0470 Conductor Size If the Z1/Z2 circuit opens, the CU3 goes into a fault state, indicated by the fault led. The fault must be corrected and the power to the CU3 cycled to clear the fault state. 1 x 2.5mm2 (14AWG) stranded 1 x 4mm2 (12AWG) solid Installation Group C in accordance with VDE 0110 Pollution Degree 3 The 24V DC version must be operated with an isolated supply. The CU3 is not intended for use with variable frequency drives. Torque Settings—terminal screws 1N⋅m (8lb⋅in) Case Material Red Polycarbonate Features Mounting 35mm DIN rail • • • • Weight 510g (1.12lbs) Electrical Life 220V AC/4A/880VA/cosϕ=3.5 220V AC/1.7A/375VA/cosϕ=0.6 30V DC/2A/60W 10V DC/0.01/0.1W 100,000 operations 500,000 operations 1,000,000 operations 2,000,000 operations Category 1 per EN 954-1 Stop category 1 2 N.O. safety outputs 1 N.C. auxiliary output Application Details Adjust to suit machine rundown and motor sensitivity. Replaceable Fuse Mechanical Life 2,000,000 operations Vibration 0.75mm (0.30in) peak, 10-55Hz Shock 30g, 11ms half-sine ➊ See Output Ratings on page 1-29 for details. Consult factory for ratings not shown. 4-70 Safety Relays Back EMF Monitors CU3 Product Selection Safety Outputs Auxiliary Outputs 2 N.O. 1 N.C. CU3 Power Supply Catalogue Number 24V AC/DC ➊ 440R-S35001 110V AC 440R-S35002 230V AC 440R-S35003 ➊ The 440R-S35001 requires an isolated supply when operating on 24V DC. Accessories Description Page Number Catalogue Number 500mA Fuse 14-6 440R-A31562 Dimensions—mm (inches) Block Diagram 45 (1.77) 120 (4.72) A1 A2 X2 X1 13 23 31 F1 73 (2.87) Stop 24VDC ~ K1 K3 K2 K3 K2 K2 K1 K1 K1 K1 Sensitivity Power 35mm DIN Rail Mounting Run K3 Fault K2 Logic Z1 Z2 Q1 K2 14 24 32 Typical Wiring Diagrams 24V DC K1 (aux) Start K2 (aux) L1 L2 L3 Stop 500mA Fuse Guard Closed & Locked A1 A2 TLS1-GD2 54 42 Z1 13 23 31 X1 K2 41 12 22 53 34 21 33 11 A1 K2 CU3 A2 Z2 14 24 32 X2 K1 K2 500mA Fuse Aux M Ground Guardlocking Safety Gate, Back EMF Detection, Automatic Reset, Monitored Output 4-71