AllansonIgnition Transformers

Allanson 421-340 Ferromagnetic Ignition Transformer for Armstrong/esso

Allanson’s Double Pole ferromagnetic transformers are designed for constant duty and provide the most reliable ignition source for commercial, residential and industrial oil applications.

SKU 3G-OTH-03291

Also listed as: 421340 · 421 340

Brand

Allanson

Item

421-340 Ferromagnetic Ignition Transformer for Armstrong/esso

Local availability & support — the Philippines

Delivery: 5–8 business days door-to-door; Bureau of Customs clearance typically 2–4 business days.
Payment: Invoicing in PHP or USD. Bank transfer and corporate PO accepted.
Ships to: Manila, Quezon City, Cebu, Davao, Batangas

Technical Specifications

Allanson

Poles

Double 

Current

23mA 

Can Size

Large Can Series 

Grounding

Mid Point Ground 

Application

OIL

Burner Type

ARMSTRONG/ESSO 

Hv Terminal

Rajah Connector 

Junction Box

EXTERNAL 

Input Voltage

120V 

Input Frequency

60Hz 

Secondary Voltage

10000V 

Burner Manufacturer

ARMSTRONG/ESSO 

Datasheet Content

[{"filename":"FerromagneticDP_SpecSheet_21-4141121_04-Sep-2025.pdf","text":"FERROMAGNETIC TRANSFORMERS\n                                                                       2721 / 2744 / 2730 / 2714 / 421 / 444 / 911 / 912\n                                                                                         SPECIFICATION GUIDE\n\n\n                    DOUBLE POLE, MID POINT GROUND MODELS\n\n Allanson’s ferromagnetic transformers are designed for constant duty and provide the most reliable ignition\n source for commercial and/or industrial oil applications.\n\n\n  Absolute Maximum Ratings\n  Model #                                           2721, 421*        2744, 444*         911*       2730, 912*         2714\n  Rated Operating Input Voltage (V)                     120               240             240           120             120\n  Operating Input Voltage Range (V)                   108-132           216-252        216-252        108-132        108-132\n  Input Supply Frequency (Hz)                            60                60             50             50             60\n  Primary Voltage - Amperes (VA)                        250               250             250           250             275\n  Secondary Voltage (RMS)                              10,000            10,000         10,000         10,000         12,000\n  Secondary Short Circuit Current (mA)                   23                23              23            23              20\n  Storage Temperature (°C)                          -40 to +80        -40 to +80      -40 to +80    -40 to +80      -40 to +80\n  Operating Temperature (°C)                        -30 to +40        -30 to +40      -30 to +40    -30 to +40      -30 to +40\n  Operating Relative Humidity (%)                        90                90              90            90              90\n  Loading Air Gap (inches)                           1/8 - 3/16        1/8 - 3/16     1/8 - 3/16     1/8 - 3/16     1/8 - 3/16\n\n * Service replacement transformers are available in select models.\n\n\n\n\n83 Commerce Valley Drive E., Markham, ON L3T 7T3                                    181 Cooper Ave., Suite 112, Tonawanda, NY 14150   #21-414\n      T: 1.800.661.7251 ● F: 1.416.752.6718                                               T: 1.631.293.3880 ● F: 1.631.293.3470        1121\n\n\n                  For more information, please visit us at allanson.com or e-mail us at cservice@allanson.com"}]

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Allanson Products

3G Electric (S) Pte. Ltd. — Singapore

Product Description

Allanson’s Double Pole ferromagnetic transformers are designed for constant duty and provide the most reliable ignition source for commercial, residential and industrial oil applications.

Supplied to the Philippines — compatible with 60 Hz installations. DHL Express delivery to Manila, Quezon City, Cebu, customs and duties handled door-to-door.

Frequently Asked Questions

What is the Allanson 421-340 ignition transformer used for?

The Allanson 421-340 is a ferromagnetic ignition transformer designed for constant-duty oil burner applications. It provides a reliable ignition source for commercial, residential, and industrial oil systems, specifically for Armstrong/Esso burners. It features a double-pole, mid-point ground design with a 10,000 V secondary output.

What are the specifications of the Allanson 421-340?

The Allanson 421-340 operates at 120 V input, 60 Hz, with a secondary voltage of 10,000 V RMS and a secondary short circuit current of 23 mA. It has a large can size, external junction box, and uses a Rajah connector for the high-voltage terminal. The storage temperature range is -40 to +80 °C.

Where to buy the Allanson 421-340 in Singapore?

You can source the Allanson 421-340 ignition transformer through 3G Electric in Singapore. We handle logistics, customs clearance, and delivery to your facility. Contact us for pricing and lead time on this model. We supply genuine Allanson components for oil burner applications.

How to install the Allanson 421-340 ignition transformer?

Ensure the transformer is mounted securely and the external junction box is properly connected to the burner wiring. The mid-point ground must be connected per local electrical codes. Maintain an air gap of 1/8 to 3/16 inches between the electrodes. Always disconnect power before installation and consult the burner manual.

Used in

Common applications for Allanson

Oil burner retrofit maintenance — Allanson CAT 1092 TYPE F transformer replacement in existing Beckett control circuits

Industrial heating-system commissioning — Control transformer installation in multi-stage flame-safeguard burner startup sequences

Plant emergency maintenance — Same-day T92 transformer procurement to restore failed ignition control voltage supply

Burner control-cabinet assembly — Allanson transformer integration in custom control-circuit designs for process-heating applications

Field technician spare-parts kit — Stocking CAT 1092 and T92 variants for mobile maintenance coverage of regional burner installations

Allanson Products

3G Electric supplies Allanson ignition transformers. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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