AllansonService Replacement Transformers

Allanson 421-655 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-03358

Also listed as: 421655 · 421 655

Brand

Allanson

Item

421-655 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 

Grounding

Mid Point Ground 

Application

OIL

Hv Terminal

Rajah Connector 

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 421-655 ferromagnetic transformer used for?

The Allanson 421-655 is a double-pole, mid-point ground ferromagnetic transformer designed for constant-duty ignition in commercial, residential, and industrial oil-burning applications. It provides a reliable 10,000 V secondary at 23 mA for oil burner ignition systems.

What are the specifications of the Allanson 421-655 transformer?

The Allanson 421-655 operates at 120 V input, 60 Hz, with a secondary voltage of 10,000 V and 23 mA current. It features double-pole construction with mid-point grounding, a Rajah connector HV terminal, and is rated for storage from -40 to +80 °C and operating from -30 to +40 °C.

Where to buy the Allanson 421-655 in Singapore?

You can source the Allanson 421-655 service replacement 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 Allanson model.

How to install the Allanson 421-655 transformer?

Ensure the transformer is mounted securely with proper clearance for ventilation. Connect the 120 V primary to the correct line and neutral, and attach the secondary Rajah connector to the oil burner ignition electrode. Verify the air gap is set between 1/8 and 3/16 inches for optimal spark.

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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