Overview
The Potter & Brumfield CB-1024B-78 is an electromechanical time delay relay designed for general-purpose industrial and commercial control applications. With a 120VAC coil voltage and adjustable time-delay range of 1.8 to 180 seconds, this relay provides reliable switching control for machinery sequencing, process timing, and motor-start applications. The CB-1024B-78 belongs to the proven CB Series family from Potter & Brumfield (now part of TE Connectivity), recognized for rugged construction and repeatable performance in harsh industrial environments.
Key Features
- 120VAC nominal coil voltage with knob-adjustable timing from 1.8 to 180 seconds
- DPDT (double-pole, double-throw) contact configuration for flexible switching logic
- 10A maximum contact current rating at 277VAC or 30VDC
- Socket mount design with quick-connect terminals for fast installation and replacement
- Time-delay function operates on relay de-energization (delay on release)
- Compact form factor suitable for panel-mount relay bases and control enclosures
Technical Specifications
- Input Coil Voltage: 120VAC
- Time Delay Range: 1.8 to 180 seconds
- Contact Configuration: DPDT (2 Form C)
- Contact Current Rating: 10A
- Contact Voltage (AC): 277VAC maximum
- Contact Voltage (DC): 30VDC maximum
- Timing Adjustment: Knob (field-adjustable)
- Mounting Style: Socket mount (8-pin)
- Terminal Style: Quick connect (0.187″ fast on terminals)
- Coil Power: Approximately 2.5 VA at 60 Hz
- Operating Temperature Range: 0–40°C (typical)
- Product Series: Potter & Brumfield CB Series
- Manufacturer: TE Connectivity (formerly Tyco Electronics/Potter & Brumfield)
Typical Applications
- Motor start and soft-start sequences requiring controlled time delays
- Machinery interlock and safety circuits with timed logic
- Process control and automation for production lines
- HVAC system sequencing and equipment staging
- Pump and compressor run-time protection and cycling control
- Conveyor belt timing and material handling automation
- Industrial alarm and notification circuits with delayed response
Compatibility & Replacements
Compatible With
- Standard 8-pin relay sockets (octal base type)
- Standard DIN rail relay bases with socket adapters
- Panel-mount relay enclosures and control cabinets
- Industrial PLC and motor-control systems requiring external timing relays
- Allen-Bradley, Siemens, and other third-party PLCs with relay I/O interfaces
Replaces / Drop-In Replacement For
- Equivalent Potter & Brumfield CB series relays with matching coil voltage and pin configuration
- Other 120VAC, 10A time-delay relays with DPDT contact configuration and 1.8–180 sec timing range
- Verify compatibility with your system integrator before ordering to ensure socket type and terminal style match your application
Works With
- Electromechanical relay control systems and hardwired logic circuits
- PLC discrete I/O modules with relay-driven control outputs
- Industrial automation platforms from Rockwell (Allen-Bradley), Siemens, Mitsubishi, and Omron
- Standard AC and DC motor-control circuits
- HVAC, process, and machinery control applications requiring timed switching
