Overview
The Amperite 50C30 is a classic thermostatic time delay relay designed for precision timing control in industrial and electrical equipment. This sealed, tube-style relay features a 50V heater voltage, normally-closed (NC) contact form with a factory-preset 30-second delay. Operating on AC, DC, or pulsating current, the 50C30 delivers reliable, repeatable timing without the need for external voltage regulation.
Key Features
- Hermetically Sealed Design: Not affected by altitude or moisture, ensuring consistent performance in harsh environments
- Normally-Closed Contacts (Delay on Break): Provides delayed contact opening for off-delay timing applications
- 30-Second Factory Preset Delay: Fixed timing eliminates the need for adjustment or calibration
- AC/DC Compatible: Can be used on A.C., D.C., or pulsating current
- Low Heater Power Consumption: Heater wattage approximately 2W, with minimum 5000-hour life and continuous operation capability
- SPST Circuit Configuration: Single Pole Single Throw, normally open or normally closed
Technical Specifications
The 50C30 combines vintage tube technology with industrial-grade reliability. The basic design uses a bi-metal switch with an attached heater, allowing precise timing without moving parts subject to wear.
Typical Applications
- Power amplifier soft-start delay in audio and RF equipment
- Relay sequencing and timing control in industrial control panels
- Load shedding and equipment startup protection
- Test equipment and oscilloscope power-on sequencing
- Vintage electronic equipment restoration and repair
- HVAC system timing and control functions
Compatibility & Replacements
Compatible With
- 8-pin octal tube sockets (standard tube base configuration)
- 50V AC or DC heater circuits
- Industrial relay cabinets and control panels
- Equipment requiring hermetically sealed time delay components
Replaces / Drop-In Replacement For
- Original Amperite 50C30 units in existing equipment
- Verify compatibility with your specific application before ordering; contact technical support for interchangeability questions
Works With
- 8-pin octal relay sockets
- Standard electrical control circuits (115V, 250V contact ratings)
- No software or network integration required














