Ditek DTK-120HW 120VAC 20A Type 1 Surge Protector

The DITEK DTK-120HW is a Type 1 panel-mount surge protection device rated for 120 VAC and 20 amps, designed to react in 1 millisecond to transient events and provide visual LED status indication.

The DTK-120HW is a compact, UL1449-listed surge arrester intended for service entrance and panel applications. With a broad 0–400 Hz operating frequency and an ultra-fast 1 ms response time, this SPD is built to intercept line transients before they reach downstream equipment. Its LED indicator gives a quick visual confirmation of operational status, making routine checks straightforward for installers and maintenance staff.

How does the DTK-120HW protect electrical panels and equipment?

The device diverts overvoltage transients away from sensitive circuitry by clamping high-voltage spikes to a safer level. As a Type 1 SPD, it is suited for installation at or near the service entrance where it addresses large surge events originating from lightning strikes or utility switching. The fast 1 millisecond response minimizes exposure time for downstream devices.

• Type 1 SPD for service entrance/panel mounting
• Clamps transient voltage to protect downstream loads
• 1 ms response time reduces surge exposure
• Handles standard residential/commercial 120 VAC lines at 20 A

What do the LED indicators tell me about the unit’s condition?

The built-in LED gives an immediate visual status so you can verify protection without instrumentation. A lit LED normally indicates the SPD is functional; an unlit or changed LED state can signal degradation or end-of-life, prompting inspection or replacement. Always confirm the LED behavior against the product instructions after installation or after suspected surge events.

• LED shows operational status at a glance
• Useful for routine maintenance checks
• Signals when replacement or further inspection is needed
• Reduces need for specialized testing tools for quick verification

Where and how should the DTK-120HW be installed for best performance?

Install the DTK-120HW at the service entrance or directly on the main distribution panel to provide upstream protection. Keep lead lengths short and follow local electrical codes and the manufacturer’s wiring diagrams to maintain optimal clamping performance. Ground connections and panel bonding are essential to ensure proper surge diversion.

• Mount at or near the service entrance/panelboard
• Use short, direct grounding conductors per installation instructions
• Follow UL1449 guidance and local electrical codes
• Verify compatibility with panel ampacity and breaker ratings

What are the key electrical specifications I should confirm before buying?

Confirm that your system uses 120 VAC and that a 20 amp rated SPD fits your panel and breaker configuration. The DTK-120HW supports a wide 0–400 Hz frequency range, making it suitable for most residential and many commercial power systems. Check UL1449 listing and the device’s Type 1 classification to ensure it meets service-entrance surge protection requirements.

• Rated for 120 VAC, 20 amp circuits
• 0–400 Hz operating frequency range
• Fast 1 ms nominal response time
• UL1449 listed for safety and compliance

Who is this for: The DITEK DTK-120HW is aimed at electricians, facilities managers, and contractors who need a UL-listed Type 1 surge protector for service entrance or main panel applications. It suits residential, light-commercial, and industrial installations that require a compact, fast-acting SPD with visual status indication. Choose this unit when you need straightforward panel-level protection that integrates into standard 120 VAC, 20 amp electrical systems and adheres to UL1449 standards.