Black EMF Monitors CU3
Documentation
- Installation Instructions (PDF 416kb)
Overview
The Guardmaster® CU3 control unit detects stopped motion and is ideal for use with guard-locking interlock switches. It interfaces 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.
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.
The 24V DC version must be operated with an isolated supply. The CU3 is not intended for use with variable frequency drives.
Note: Guardmaster Safety Relays have been marketed by Rockwell Automation under the trade name "Minotaur" in the past
- Category 1 per EN 954-1
- Stop category 1
- Two N.O. safety outputs
- One N.C. auxiliary output
- Supports automatic/manual and monitored reset
- Motor voltage up to 500V max.
Specs
| Safety Ratings | ||
| Standards | EN 954-1, ISO 13849-1, IEC/EN 60204-1, IEC 60947-5-1, ANSI B11.19, AS4024.1 | |
| Safety Classification | Cat. 1 per EN 954-1 (ISO 13849-1), SIL CL1 per EN IEC 62061, PL c per ISO 13849-1 | |
| Functional Safety Data ⋆ | PFHD: See website | |
| Note: For up-to-date information, visithttp://www.ab.com/safety/ | MTTFd: See website | |
| Suitable for performance levels Ple (according to ISO 13849-1:2006) and for use in SIL3 systems (according to IEC 62061) depending on the architecture and application characteristics | ||
| Certifications | CE marked for all applicable directives, cULus, c-Tick, and TÜV | |
| Power Supply | ||
| Input Power Entry | 24V AC/DC, 115/230V AC | |
| Power Consumption | ||
| Motor Voltage | 500V max. | |
| Inputs | ||
| Safety Inputs | Z1/Z2 Motor Voltage | |
| Reset | Automatic/Manual | |
| Outputs | ||
| Safety Contacts | 2 N.O. | |
| Auxiliary Contacts | 1 N.C. | |
| Rated Impulse withstand Voltage | 2500V | |
| Switching Current @ Voltage, Min. | 10 mA/10V | |
| Fuses, Output | 5 A quick acting (external) | |
| Electrical Life (Operations) | 220V AC/4 A/880VA cosf = 0.35…0.1 M | |
| 220V AC/1.7 A375VA cosf = 0.6…0.5 M | ||
| 30V DC/2 A/60 W = 1 M | ||
| 10V DC/0.01 A/0.1 W = 2 M | ||
| Mechanical Life | 2,000,000 operations | |
| Utilization Category | ||
| Inductive: B300: AC-15 | 5 A @ 250V AC | 5 A @ 120V AC |
| Inductive: DC-13 | 3 A/24V DC | |
| Environmental and Physical Characteristics | ||
| Enclosure Type Rating/ | IP40, DIN 0470/ | |
| Terminal Protection | IP20 DIN 0470 | |
| Operating Temperature [C (F)] | -10…+55 ° (14…131 °) | |
| Vibration | 0.75 mm (0.30 in) peak, 10…55 Hz | |
| Shock | 30 g, 11 ms half-sine | |
| Mounting | 35 mm DIN Rail | |
| Weight [g (lb)] | 510 (1.12) | |
| Conductor Size, Max. | 1 x 2.5 mm2 (14 AWG) stranded, 1 x 4 mm2 (12 AWG) solid | |
⋆ Usable for ISO 13849-1:2006 and IEC 62061. Data is based on the following assumptions:
- Mission time/Proof test interval of 20 years
- Functional test at least once within six-month period
