AllansonService Replacement Transformers

Allanson 421-BT387 Ferromagnetic Service Replacement 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-03364

Also listed as: 421BT387 · 421 BT387

Brand

Allanson

Item

421-BT387 Ferromagnetic Service Replacement 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 

Can Size

Large Can Series 

Grounding

Mid Point Ground 

Application

OIL

Hv Terminal

Thumb Screw 

Junction Box

INTERNAL 

Input Voltage

120V 

Input Frequency

60Hz 

Secondary Voltage

10000V 

Datasheet Content

[{"filename":"FerromagneticDP_SpecSheet_21-4141621.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\nAbsolute Maximum Ratings\nModel #                              2721, 421, 2741 2744, 444       911       2730, 912       2714         2729            2742\nRated Operating Input Voltage (V)          120          240          240          120           120          220             220\nOperating Input Voltage Range (V)       108-132       216-252      216-252      108-132      108-132      198-242         198-242\nInput Supply Frequency (Hz)                 60           60           50           50           60           50              50\nPrimary Voltage - Amperes (VA)             250          250          250          250           275          250             250\nSecondary Voltage (RMS)                  10,000        10,000       10,000       10,000       12,000       10,000          12,000\nSecondary Short Circuit Current (mA)        23           23           23           23            20           23              20\nStorage Temperature (°C)               -40 to +80    -40 to +80   -40 to +80   -40 to +80   -40 to +80   -40 to +80      -40 to +80\nOperating Temperature (°C)             -30 to +40    -30 to +40   -30 to +40   -30 to +40   -30 to +40   -30 to +40      -30 to +40\nOperating Relative Humidity (%)             90           90           90           90            90           90              90\nLoading Air Gap (inches)               1/8 - 3/16    1/8 - 3/16   1/8 - 3/16   1/8 - 3/16   1/8 - 3/16   1/8 - 3/16      1/8 - 3/16\n\n\n\n\n83 Commerce Valley Drive E., Markham, ON L3T 7T3                           99 Adams Blvd., Farmingdale, New York 11735                #21-414\n      T: 1.800.661.7251 ● F: 1.416.752.6718                                    T: 1.631.293.3880 ● F: 1.631.293.3470                     1621\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.

Frequently Asked Questions

What is the Allanson 3G-OTH-03364 ferromagnetic transformer used for?

The Allanson 3G-OTH-03364 is a double-pole, mid-point ground ferromagnetic service replacement transformer designed for constant-duty ignition in commercial, residential, and industrial oil-fired burners. It provides a reliable 10,000 V secondary at 23 mA for consistent spark ignition in oil applications.

What are the specifications of the Allanson 3G-OTH-03364?

The Allanson 3G-OTH-03364 has a 120 V, 60 Hz input, 10,000 V secondary, 23 mA secondary short-circuit current, and 250 VA rating. It features a double-pole, mid-point ground design with an internal junction box, thumb-screw HV terminal, and large can series size. Operating temperature range is -30 °C to +40 °C.

Where to buy the Allanson 3G-OTH-03364 in Singapore?

3G Electric supplies the Allanson 3G-OTH-03364 ferromagnetic transformer to Singapore. We source and deliver this OEM ignition component, handling logistics, customs clearance, and delivery to your facility. Contact us for pricing and lead time on this service replacement transformer for oil burners.

How to install the Allanson 3G-OTH-03364 transformer?

Install the Allanson 3G-OTH-03364 by mounting it securely in the burner junction box, connecting the 120 V primary to the internal junction box terminals, and attaching the 10,000 V secondary via the thumb-screw HV terminal. Ensure the air gap is set to 1/8–3/16 inches for proper spark. Follow Allanson's installation instructions for safe operation.

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 service replacement transformers. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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