OMRON CVM1-BC103 Backplane Base Unit (145752)
The OMRON CVM1-BC103 (part number 145752) is a base unit (backplane) for the CVM1 programmable logic controller series. It provides the mechanical and electrical interconnection between the CPU, power supply, and up to three I/O or special function modules. This unit is essential for building compact CVM1 automation systems.
Physical and Electrical Characteristics
The backplane measures 115 mm (H) x 260 mm (W) x 45 mm (D) and is constructed from flame-retardant plastic. It features three module slots: slot 0 is typically reserved for the CPU module (e.g., CVM1-CPU01), slot 1 and 2 can hold any CVM1-series I/O unit (digital, analog) or communication modules (RS-232C, RS-422). Power to modules is supplied via a 5 V DC bus (max 2 A) and 24 V DC field power bus (max 1 A) derived from the external power supply connected to the base unit. A green LED indicates backplane power status.
Compatibility and System Expansion
The CVM1-BC103 supports a maximum I/O count of 128 points when fully populated with 16-point modules. For larger systems, the CVM1-BC103 can be connected to an expansion base unit (CVM1-BC203) using a flat cable (CV500-CN221). Up to three expansion racks are allowed, providing a total of up to 512 I/O points. The backplane automatically assigns unit numbers based on slot position.
Environmental and Mechanical Standards
Operating temperature: 0°C to 55°C. Storage: -20°C to 75°C. Humidity: 35% to 85% non-condensing. Vibration resistance: 2 g (10–57 Hz). Shock resistance: 15 g for 11 ms. The unit meets UL508 and CSA C22.2 No.142 certifications. It is designed for DIN rail mounting (EN 60715) with optional screw-mount brackets.
Typical Applications and Maintenance
The CVM1-BC103 is found in legacy injection molding machines, conveyor control systems, and small packaging lines. Maintenance involves periodic cleaning of the backplane’s gold-plated card-edge connectors using an approved contact cleaner. No software configuration is required for the backplane itself.
