AllansonIgnition Transformers

Allanson 421-BT387-SF Ferromagnetic Ignition Transformer

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-03299

Also listed as: 421BT387SF · 421 BT387 SF

Brand

Allanson

Item

421-BT387-SF Ferromagnetic Ignition Transformer

Local availability & support — Singapore

Local office: 20 Woodlands Link #09-05, Singapore 738733
Phone: +65 8878 8355
Delivery: Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment: Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to: Singapore

Technical Specifications

Allanson

Poles

Double 

Current

23mA 

Grounding

Mid Point Ground 

Application

OIL

Secondary Voltage

10000V 

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"}]

Technical Documents

No technical documents available for this product.

Request documentation →

Not sure this is the right part? Get a recommendation.

Need installation or engineering help?

Installation, commissioning, maintenance plans, system design, and bundled product + service quotes — one team handles the full scope.

Talk to an engineer

Ask a question

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.

Frequently Asked Questions

What is the Allanson 3G-OTH-03299 ignition transformer used for?

The Allanson 3G-OTH-03299 is a double-pole ferromagnetic ignition transformer designed for constant-duty commercial, residential, and industrial oil-burner applications. It provides a reliable 10,000 V secondary voltage at 23 mA to ignite fuel oil in boilers, furnaces, and other oil-fired equipment.

What are the specifications of the Allanson 3G-OTH-03299?

The Allanson 3G-OTH-03299 is a double-pole, mid-point grounded ferromagnetic transformer with a secondary voltage of 10,000 V RMS and a secondary short-circuit current of 23 mA. It operates at 120 V input (108–132 V range), 60 Hz, with a 250 VA rating. Storage temperature is -40 to +80 °C; operating temperature is -30 to +40 °C.

Where to buy the Allanson 3G-OTH-03299 in Singapore?

3G Electric supplies the Allanson 3G-OTH-03299 ferromagnetic ignition transformer to customers in Singapore. We handle logistics, customs clearance, and delivery to your facility. Contact us for pricing and lead time on this model.

How to install the Allanson 3G-OTH-03299 ignition transformer?

Install the Allanson 3G-OTH-03299 by mounting it securely in the oil burner control circuit, ensuring the input voltage matches the 120 V rating. Connect the high-voltage secondary leads to the ignition electrodes with a loading air gap of 1/8 to 3/16 inches. Follow the manufacturer's wiring diagram and local electrical codes.

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.

Browse all Allanson products →Contact our engineers →