RX27 4H-30W Ceramic Wirewound Power Resistor (120 Ohm)

The RX27 4H-30W Ceramic Wirewound Power Resistor (120 Ohm) is a heavy-duty passive electronic component engineered for high power dissipation and superior reliability. Encased in a fireproof ceramic block and sealed with an inorganic cement, this resistor is designed to limit current, drop voltage, or safely dissipate excess electrical energy as heat. It features a heavy-duty metal mounting bracket, allowing it to be bolted directly to a metal chassis for maximum thermal cooling.

Key Specifications:

• Category: Electronic Components / Passive Components / Power Resistors

• Product Type: Ceramic Encased Wirewound Resistor (Cement Resistor)

• Model / Series: RX27 (4H-30W variant)

• Power Rating: 30 Watts (30W)

• Resistance Value: 120 Ohms (120R)

• Tolerance: ±5% (Class J)

• Electrical Connection: Quick-connect male spade terminals (Faston type)

• Housing Material: High-temperature ceramic casing with fireproof cement potting

• Mounting: Included zinc-plated metal chassis-mount bracket with a pre-drilled screw hole

Key Features:

• Excellent Heat Dissipation – The ceramic casing combined with the metal bracket allows the resistor to be bolted directly to a metal heat sink or chassis, keeping operating temperatures manageable under heavy continuous loads.

• Flame & Moisture Resistant – Completely sealed in an inorganic, fireproof cement that will not ignite or melt under severe electrical overloads, ensuring maximum safety inside enclosed electrical panels.

• Solderless Installation – Equipped with top-mounted spade terminals, allowing for fast, secure push-on wiring with standard crimp connectors without the need for a soldering iron.

• High Stability & Surge Handling – The internal wirewound construction provides highly stable resistance values across a wide operating temperature range and is capable of absorbing short-term surge currents exceptionally well.

Ideal For:

• EV Pre-Charge Circuits: Used in high-voltage electric vehicle and solar energy systems to slowly charge inverters and capacitors before the main contactor closes, preventing damaging high-current sparks.

• Motor Control & VFDs: Dynamic braking resistors for small variable frequency drives or DC motor controllers.

• Power Supply Testing: Acting as a safe "dummy load" for discharging batteries or testing power supply outputs.

• Automotive Custom Wiring: Current limiting, LED load balancing, and voltage dropping in custom 12V/24V electrical builds.

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