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Seifert 503251 KH503 250W 115V Control Cabinet Resistor Heater, 5.3" x 3.2" x 4.4"


Seifert KH 503-251 Control Cabinet Heater
Seifert 503251 KH503 250W 115V Control Cabinet Resistor Heater
 
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Price: $163.16
Note: Delivery: 4 -7 Business Days
MFG P/N: 503251
MFG: Seifert
Weight (lbs): 2

Quantity in Stock :10


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Product Code: 503251
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Description
 

Seifert KH 503-251 250W 120V Fan-Assisted Enclosure Heater, 20 CFM DIN Rail Mount

250W Seifert fan-assisted control cabinet heater with 120V input, 20 CFM airflow, a self-regulating PTC resistor, pilot light, overheat protection, and DIN-rail mounting.

Why Choose the Seifert KH 503-251?

The Seifert KH 503-251 is a 250W fan-assisted control cabinet heater rated for 120V, 50/60 Hz operation. Its integrated 20 CFM fan circulates warm air throughout the enclosure, helping maintain a more uniform temperature and reduce condensation around sensitive electrical equipment.

The heater combines a self-regulating PTC resistor with a pilot light and built-in overheat protection. Its anodized aluminum housing and DIN-rail mounting format support efficient installation in industrial control panels and automation cabinets.

🔥 250W Heating Power

Provides controlled heat for compact and mid-size enclosures

💨 20 CFM Airflow

Moves warm air through the cabinet to reduce cold areas

⚡ 120V Operation

Matches common 120V, 50/60 Hz control cabinet power

🌡️ PTC Heating Element

Self-regulating resistor responds to surrounding temperature

⚠️ Confirm Supply Voltage and Installation Clearance

Verify the required supply voltage before installation. The technical specifications list this model at 120V, 50/60 Hz with a maximum current of 2.4A. Maintain clear airflow around the fan and install the IP20 heater inside a suitable protective enclosure.

📋 Warm-Air Circulation Helps Limit Moisture

Temperature swings inside electrical cabinets can lead to humidity and condensation. By distributing warm air at 20 CFM, the KH 503-251 helps protect internal equipment and supports the minimum temperature needed for reliable operation.

Key Features and Benefits

  • 250W fan-assisted control cabinet heater
  • 120V, 50/60 Hz rated voltage
  • 20 CFM integrated fan airflow
  • Self-regulating PTC resistor
  • Pilot light for operating status
  • Built-in overheat protection
  • Anodized aluminum housing
  • DIN-rail mountable design
  • Compatible with thermostat control
  • IP20 protection rating
  • CE and cURus approvals
  • RoHS compliant

Technical Specifications

Brand Seifert
Model KH 503-251
Product Type Fan-Assisted PTC Enclosure Heater
Heating Power at 50°F 250W
Rated Voltage 120V, 50/60 Hz
Maximum Current 2.4A
Fan Airflow 20 CFM
Heating Element Self-Regulating PTC Resistor
Operating Temperature -13°F to 158°F (-25°C to 70°C)
Dimensions 5.3 in. H x 3.2 in. W x 4.4 in. D
Housing Anodized Aluminum
Connection 3 Screw Terminals for 14 AWG Stranded or Rigid Wire
Mounting DIN Rail
Ingress Protection IP20
Approvals CE, cURus
Compliance RoHS

🔧 Installation and Setup Overview

1. Confirm Heater Size: Verify that 250W of output meets the enclosure heat-loss and minimum-temperature requirements.

2. Check Electrical Supply: Confirm a 120V, 50/60 Hz source and wiring suitable for the specified current.

3. Mount Securely: Install the heater on DIN rail with open space around the fan inlet and warm-air outlet.

4. Connect Wiring: Terminate compatible 14 AWG stranded or rigid conductors at the three screw terminals.

5. Test Operation: Confirm the pilot light, fan airflow, and heating function after power is applied.

Follow applicable electrical codes and the manufacturer’s installation instructions.

🏭 Typical Applications

The KH 503-251 is designed for control panels, automation enclosures, outdoor machinery cabinets, electrical boxes, and other protected housings that need 120V enclosure heating and active air circulation.

✅ Selection Notes

Use this model when the application requires 250W of heating power from a 120V supply. A thermostat can be added when automatic temperature-based control is required.




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