Configured for reduced-voltage starting of large 3-phase induction motors in Logix-driven MCC networks, the Allen-Bradley 150-F970NBE (150-F SMART MOTOR CONTROLLER) provides direct thyristor phase-angle execution at 970 A.

Catalog Suffix Decoding

• 150-: Bulletin 150 SMC Flex solid-state reduced voltage controller
• F: Open-type enclosure, no integral disconnect
• 970: 970 A rated operational current at 40 deg C (approx 800 hp @ 460 VAC)
• N: Control voltage 100-120 VAC (universal low-range AC)
• B: Standard logic board, DeviceNet/EtherNet/IP daughterboard ready
• E: Standard ramp profile, no pump/brake specialization, external bypass expected

Hardware Specifications

EtherNet/IP Node Behavior and Firmware Flash Compatibility

The 150-F970NBE interfaces with ControlLogix/CompactLogix MCC assemblies via 150-COMM-EN or 150-COMM-DN modules using CIP explicit messaging over EtherNet/IP. Firmware flash is locked to SMC Flex v4.x images; loading 150-F625 or SMC-3 images corrupts the standard ramp register and halts POST at 0x8F. I/O density scaling is fixed: 3 thyristor legs, 4 discrete status outputs, 2 analog ramp-monitor channels mapped to Logix tags at 10 ms RPI. Backplane bus velocity licence is not applicable—termination is panel-wire, not rack-plugged. At 970 A the controller expects an externally wired AC-3 bypass contactor driven by the run-ready relay to remove thyristor steady-state loss from the thermal budget.

Ordering Info

• 1 x 150-F970NBE SMC Flex solid-state soft starter, open type
• 1 x Wiring and parameter quick-reference label sheet

Panel Mounting and Conductor Rules

• Mount vertically on rigid steel with 150 mm top clearance and 75 mm bottom clearance for convection off the thyristor heat sink.
• Terminate line lugs with 2 x 500 kcmil Cu conductors per phase (75 deg C rating), torque to 55 N·m.
• Separate 100-120 VAC control wiring from 460 VAC power bus by 250 mm or run in bonded metallic conduit.
• Bond PE terminal to panel ground stud with conductor sized per NEC 250.122 for 970 A service.
• Forced airflow of 0.8 m³/s across rear fins is mandatory if ambient exceeds 40 deg C.

Frequently Asked Questions

Q: Can the 150-F970NBE run continuously on the thyristor bridge without bypass?

A: No. At 970 A conduction loss exceeds 4 kW. Running unbypassed overheats the heat sink within 8 minutes even at 40 deg C ambient. External AC-3 bypass must close after ramp completion.

Q: What control voltage tolerance is allowed on the 100-120 VAC supply?

A: 90-132 VAC. Below 90 VAC the logic board resets; above 132 VAC the control transformer saturates and zero-cross detection shifts by 0.9 ms per 10 V overvoltage.

Q: Does suffix E include pump or braking profiles?

A: No. Suffix E is the standard ramp only (S-curve soft start/soft stop). Pump control and DC-injection braking require suffix B in the feature position, not present here.

Q: What is the forward voltage drop across the SCRs at 970 A?

A: Approx 1.5 V per anti-parallel pair. Conduction loss = 1.5 V x 970 A x 3 phases = 4365 W to rear heat sink. Panel ventilation must extract this at full load.

Q: Can EtherNet/IP and DeviceNet adapters be fitted at the same time?

A: No. The logic daughterboard accepts one comms module. Swapping 150-COMM-DN for 150-COMM-EN requires power down and CIP parameter remap; dual fit bricks the HIM header.

Q: Minimum conductor temperature class for power terminals?

A: 75 deg C copper. Using 60 deg C conductors forces ampacity derating to 860 A, voids the 970 A nameplate and causes overload trip at 90% FLC.

Q: Is hot-swap replacement on a live MCC bus permitted?

A: No. Thyristor stacks and DC control lack staged insertion. Inserting under line voltage arcs the terminals and corrupts the ramp register. De-energize line and control first.

Q: How is firmware flashed on bench?

A: Via HIM port with 1756-USB cable and SMC Flex Flash tool. Image must match 150-F hardware ID 0x970. Mismatched flash halts boot at POST 0x8F and requires factory recovery.