Ditek DTK-2MHLP24F Alarm Panel Protector (No Base)

The Ditek DTK-2MHLP24F Alarm Panel Protector (No Base) is a modular low-voltage surge protection device designed for 24V data and signaling circuits used with fire alarm, security, access-control, and related electronic systems. It protects two circuit pairs per module and uses DITEK’s load-removal technology, which opens the protected circuit if the surge module becomes compromised.

This specific DTK-2MHLP24F is the module-only version. A compatible Snap-Track mounting base is required for installation but is not included. DITEK identifies the DTK-2MHLP24FWB as the corresponding version supplied with a mounting base.

---

Product Functions

• Protects two 24V low-voltage circuit pairs
• Protects fire alarm data and signaling circuits
• Provides differential line-to-line protection
• Provides common-mode line-to-ground protection
• Uses hybrid SAD and GDT surge protection technology
• Provides open-circuit failure operation
• Removes the load when the module is compromised
• Supports AC and DC low-voltage circuits
• Uses a field-replaceable plug-in module
• Works with DITEK Snap-Track mounting bases
• Allows multiple modules to share a common grounding point
• Provides up to 20,000A surge-current protection

---

24V Circuit Protection

The DTK-2MHLP24F is specifically designed for:

Service Voltage: 24V

Maximum Continuous Operating Voltage (MCOV): 33V

Clamping Voltage: 39V.

These ratings make the module suitable for compatible 24V low-voltage signaling and data circuits requiring protection against transient voltage events.

---

Two-Pair Protection

Each DTK-2MHLP24F protects:

2 circuit pairs per module.

DITEK’s multi-base architecture can accommodate multiple 2MHLP modules, allowing as many as 10 circuit pairs to be protected while sharing a common ground point.

This modular arrangement is useful for fire alarm and control panels with several field circuits requiring surge protection.

---

Open-Circuit Failure Mode

The F version of the 2MHLP family uses:

Failure Mode: Open Circuit.

DITEK describes this design as load removal technology. If the surge protection module becomes compromised, it opens the circuit rather than shorting the circuit to ground.

This distinguishes it from the DTK-2MHLP24B, which uses a short-to-ground notification/failure approach.

---

Surge Protection Technology

The DTK-2MHLPF Series uses a hybrid design combining:

SAD — Silicon Avalanche Diode

and

GDT — Gas Discharge Tube

technologies.

This multi-stage architecture is designed to divert damaging transient energy away from sensitive alarm-panel electronics and connected low-voltage equipment.

---

Protection Modes

The DTK-2MHLP24F provides:

Differential Mode: Line-to-Line (L-L)

Common Mode: Line-to-Ground (L-G).

This provides protection against transients appearing between circuit conductors as well as surges referenced to ground.

---

Surge Current Capacity

Published DITEK specifications identify:

Surge Current Rating: 20,000A

Maximum Continuous Current: 1A.

The 20kA rating represents the surge-handling capability of the current 2MHLPF Series design.

---

Fire Alarm Panel Protection

DITEK specifically identifies 2MHLP modules for protection of fire alarm circuits. The company’s fire-alarm surge protection reference lists the series for protecting two pairs of SLC, IDC/PIV, NAC, or dialer circuits, while DITEK’s current 2MHLPF data sheet specifically lists fire alarm SLC, PIV, and IDC circuits among applications.

However, DITEK’s installation documentation specifically cautions not to use DTK-2MHLPxxF modules for PIV or NAC circuits. For an actual installation, this installation-guide restriction should control product selection.

---

Module Only – No Base

The DTK-2MHLP24F is supplied as:

Module Only

Mounting Base: Not included.

DITEK’s current ordering information states that adding “WB” to the part number specifies the module with base.

Therefore:

DTK-2MHLP24F: Module only, no base

DTK-2MHLP24FWB: Module with Snap-Track mounting base.

The module connects to the compatible mounting base through an edge-card connection.

---

Field-Replaceable Design

The DTK-2MHLP24F is designed as a field-replaceable surge module.

The hardwired field connections remain on the compatible mounting base, while the protection module plugs into that base. This arrangement allows a compromised module to be replaced without rebuilding all associated field wiring.

DITEK also offers the DTK-2MHLPTM test module kit for applicable 2MHLP installations.

---

Electrical Information

Service Voltage: 24V

MCOV: 33V

Clamping Voltage: 39V

Surge Current Rating: 20,000A

Maximum Continuous Current: 1A

Protection Modes: L-L / L-G

Failure Mode: Open Circuit

Protected Circuits: Two pairs

AC/DC Compatibility: Both AC and DC low-voltage circuits.

---

Installation Information

The DTK-2MHLP24F plugs into a compatible DITEK Snap-Track mounting base. Field wiring terminates at the base rather than directly on the replaceable module. The base supports hardwired connections from 30–12 AWG.

DITEK installation instructions distinguish the UN-PROTECTED field side from the PROTECTED alarm-panel side. Field circuit wiring enters the unprotected side, while conductors leaving the protector toward the alarm-panel inputs connect on the protected side.

Proper grounding and separation of protected and unprotected wiring are important to effective surge protection. DITEK publishes a dedicated installation guide for the 2MHLP modules and bases.

DTK-2MHLP24F Datasheet