Mitsubishi R38B MELSEC iQ-R 8‑Slot Main Base Unit

Mitsubishi Electric MELSEC iQ‑R series main base unit. Provides 8 slots for installing power supply, CPU, I/O and intelligent function modules. Rigid base with M4 mounting holes and dedicated DIN rail adapter (R6DIN1, sold separately). Supports main base expansion with up to 7 extension base units, total 64 modules across up to 8 bases. High‑speed iQ‑R backplane bus ensures low‑latency communication between modules for complex multi‑axis motion control and high‑speed data logging.

Applications:

• Central chassis for MELSEC iQ‑R series PLC systems

• Hosting power supply, CPU and I/O modules in factory automation

• Single‑CPU or multi‑CPU configurations (standard main base unit)

• Machine control panels and industrial automation racks

Core Specifications:

• Number of I/O slots: 8

• Power supply slot: 1 (leftmost slot)

• CPU slot: 1 (second slot from left)

• 5 V DC internal current consumption: 0.71 A

• Mounting: panel mount (M4 screws) or DIN rail via R6DIN1 adapter (optional)

• Protection rating: IP20

• Dimensions (H × W × D): 101 mm × 328 mm × 32.5 mm

• Weight: approx. 0.55 kg

• Mounting hole size: M4 screw hole or ø4.5 mm hole

• Operating temperature: 0 °C … 55 °C

• Storage temperature: –20 °C … 75 °C

• Humidity: 10 % … 90 % RH (non‑condensing)

• Certifications: CE, UL, cUL, KC, EAC, ABS, BV, DNV GL, LR, NK, RINA

• RoHS compliant

Slot Allocation:
Slot 0 (leftmost) – power supply module
Slot 1 – CPU module (main base) or head module (remote I/O)
Slots 2‑7 – I/O modules and intelligent function modules

System Integration:

• This main base unit belongs to the Mitsubishi Electric MELSEC iQ‑R series.

• Up to 7 extension base units can be connected via RC series extension cables (0.6 m, 1.2 m, 3 m, 5 m, 10 m).

• DIN rail mounting requires optional R6DIN1 adapter (sold separately).

• For detailed installation, power budgeting and expansion cabling, refer to the MELSEC iQ‑R Module Configuration Manual.

Related Products:

• Lower slot count → R33B (3 slots) or R35B (5 slots)

• Current model → R38B (8 slots)

• Higher slot count → R312B (12 slots)

• DIN rail mounting adapter → R6DIN1