Castair TD100 — Electronic Time Delay, 18–240 Volt, 1–1023 Second Range
The Castair TD100 is an adjustable electronic time delay relay that operates across a wide voltage range of 18 to 240 volts and provides a delay interval adjustable from 1 to 1,023 seconds. On air compressor systems, time delay relays serve several important functions: they prevent short-cycling on motor restart, allow pressure to equalize across the system before the motor re-engages, and protect the motor from the thermal stress of rapid successive starts. The TD100''s broad voltage range makes it compatible with both single-phase 120V shop setups and 240V compressors without needing a separate part for each voltage.
Short-cycling — where the compressor motor starts, shuts off as the pressure switch trips, and immediately restarts because pressure dropped again — is one of the fastest ways to burn out a motor. A properly set time delay ensures the motor does not restart until enough time has passed for the motor windings to cool and the pressure to stabilize. For 5 HP and larger motors, a 30–60 second restart delay is common practice. The TD100''s 1-to-1023-second range gives you enough adjustment room to handle small single-phase motors through large industrial units.
Key Features
- Voltage Range: 18 to 240 volts — covers 120V single-phase and 240V single or three-phase compressor applications
- Delay Range: 1 to 1,023 seconds (approximately 17 minutes maximum) — wide enough for any compressor restart delay application
- Adjustable Timing: Set the delay at installation to match your motor size and system requirements
- Electronic Design: More consistent and reliable than mechanical or pneumatic time delay devices
- Motor Protection: Prevents short-cycling that causes premature motor winding failure
- Compressor System Compatible: Works with Cast Air compressor electrical panels and controls
Technical Specifications
- Part Number: TD100
- Input Voltage: 18–240 Volt AC
- Delay Range: 1–1,023 seconds
- Type: Electronic time delay relay
- Manufacturer: Cast Air (Castair)
- Price: 2.35
Typical Applications
- Adding restart delay protection to any Cast Air compressor to prevent short-cycling after the pressure switch trips
- Motor protection on 5 HP and larger compressors where rapid restart creates thermal stress on windings
- Facilities where the compressed air demand causes the pressure to drop and recover quickly — the TD100 ensures the motor gets adequate cool-down time between starts
- Replacing a failed time delay relay in an existing compressor control panel
- New panel builds where time delay relay is specified
Why Buy From OEM Diagnostic Tools?
The TD100''s wide voltage and timing range makes it a versatile component for many compressor electrical configurations. We can help confirm it will work in your specific panel layout and voltage. Free shipping, phone support at 866-217-0063, full Cast Air warranty.
Call 866-217-0063 for quick answers and help!
