The MPU-32 series Motor Protection Unit is used to provide current and temperature-based protection, metering, and data-logging for three-phase, low-voltage, medium-horsepower induction motors. This relay is ideal for retrofitting and upgrading obsolete or aging motor protection using existing CTs. The MPU-32 can be programmed using the front-panel operator interface, the TIA-232 port, or an optional communications network. See the PMA Family of Panel Mount Adapter Kits to replace common obsolete relays.
Motor Protection Unit
Three ac-current inputs
Earth-leakage-CT input
Programmable digital input
24 V dc source for digital input
Programmable 4–20-mA analog output
Onboard temperature-sensor input
100-Ω-Platinum RTD or PTC
Three programmable output relays
Local RS-232 communications, optional network communications
PC-interface software (SE-Comm-RIS)
4 line x 20 character backlit LCD display
Keypad for programming and display selection
4 LEDs; 1 user programmable
Current Input Module (MPU-CIM) The MPU-CIM Current Input Module is the interface between the MPU-32 relay and the 5-A-secondary, 1-A-secondary, and sensitive current transformers. The MPU-CIM is ordered separately from the MPU-32 and can be surface- or DIN-rail mounted. Wire-clamping terminals are standard, but the MPUCTI is available for those requiring ring-tongue terminals.
Overload
Dynamic thermal model
Communications
Ground fault
Current unbalance/Phase loss/Phase reverse (current)
RTD temperature
Phase loss/Phase reverse (current)
Overcurrent
Jam
Undercurrent
Extends motor life and prevents insulation failures and fires
Provides protection through starting, running, and cooling cycles
Remotely view measured values and event records, reset trips, and access setpoints
Prevents catastrophic failures and fires
Prevents overheating due to unbalanced phases
RTD temperature protection (MPS-RTD module) for high-ambient or loss-of-ventilation protection
Detects unhealthy supply conditions
Prevents catastrophic failures and fires and extends motor life
Prevents motor damage by detecting mechanical jams or excessive loading