AllansonService Replacement Transformers

Allanson 421-BT104 Ferromagnetic Service Replacement Transformer

SKU 3G-OTH-03318

Also listed as: 421BT104 · 421 BT104

Brand

Allanson

Item

421-BT104 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

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

10000 Volt 

Datasheet Content

[{"filename":"FerromagneticDP_SpecSheet_21-4141121.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                                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       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

The Allanson 3G-OTH-03318 is a ferromagnetic service replacement transformer for oil applications, featuring a large can series design with internal junction box and mid-point grounding. It operates on 120V input at 60Hz, delivering a secondary voltage of 10000 volts with 23mA current, and includes a thumb screw HV terminal.

Frequently Asked Questions

What is the Allanson 3G-OTH-03318 ferromagnetic transformer used for?

The Allanson 3G-OTH-03318 is a service replacement ferromagnetic transformer designed for constant-duty ignition in commercial and industrial oil burner applications. It provides a reliable 10,000 V secondary voltage at 23 mA for oil-fired equipment.

What are the specifications of the Allanson 3G-OTH-03318?

The Allanson 3G-OTH-03318 has a 120 V input at 60 Hz, 10,000 V secondary voltage, 23 mA secondary short circuit current, and 250 VA rating. It features mid-point grounding, an internal junction box, thumb screw HV terminals, and operates from -30 °C to +40 °C.

Where to buy the Allanson 3G-OTH-03318 in Singapore?

3G Electric supplies the Allanson 3G-OTH-03318 ferromagnetic transformer to Singapore. We source and deliver this service replacement transformer, handling logistics, customs clearance, and delivery to your facility. Contact us for availability and lead time.

How to install the Allanson 3G-OTH-03318 transformer?

Install the Allanson 3G-OTH-03318 by mounting it securely in the oil burner junction box. Connect the 120 V primary to the input terminals and the 10,000 V secondary to the ignition electrodes using the thumb screw HV terminals. Ensure the loading air gap is set between 1/8 and 3/16 inches for proper 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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