Mighty Mule FM362-D RB502 Transformer - 14 Volt - AC - Operator Only

Mighty Mule FM362-D RB502 Transformer - 14 Volt - AC - Operator Only

The RB502 is a 14 volt AC transformer used with specific Mighty Mule and GTO/Linear PRO gate opener systems. It supplies low-voltage AC power to the operator system as specified by the original model and board design.

This transformer is often replaced when the operator battery is not charging, the transformer is missing or damaged, or the original unit has failed. Low battery symptoms can also come from a bad battery, damaged wire, failed charge fuse, or control board issue, so the transformer should be tested as part of the charging system.

The most important ordering point is voltage and generation. RB502 is a 14VAC transformer for certain models. It should not be confused with RB570, which is an 18VAC 40VA transformer for many UL-rated models. Using the wrong transformer can create charging problems or component damage.

Compatible With

This part is commonly associated with the following Mighty Mule, GTO, and Linear PRO applications. Always match the part number, operator model, and parts diagram before ordering because older and newer generations may use similar-looking parts.

• Mighty Mule 362-D where RB502 is specified
• Mighty Mule 402 where RB502 is specified
• Mighty Mule 700 / 1000 references where RB502 is specified
• GTO / Linear PRO 1000 and 1200 applications where 14VAC RB502 is specified
• Older GTO or Mighty Mule operator applications that call for RB502 14VAC transformer
• Not compatible with AQ250 or AQ251 boards where manufacturer notes exclude it
• Not a substitute for RB570 18VAC transformer applications

Features and Specifications

Also Known As / Related Part Numbers

• RB502
• LIN-RB502
• GTO RB502
• Mighty Mule RB502
• 14VAC transformer
• 14 Volt AC transformer
• GTORB502
• PRO1000 transformer
• PRO1200 transformer
• FM362-D transformer

Technician Note

Check transformer output with the correct meter setting and confirm that power is reaching the board. If the transformer tests good but the battery will not charge, inspect wiring, fuses, and the board charge circuit.

Before Ordering

• Confirm the operator manual calls for RB502 or 14VAC transformer input.
• Do not substitute RB570 18VAC for this part.
• Verify the operator board is not AQ250 or AQ251 if those are excluded.
• Inspect low-voltage wire from transformer to control box.
• Check the battery and charge fuse before replacing multiple parts.

Important Ordering Warnings

• Using the wrong transformer voltage can damage components or prevent proper charging.
• Line-voltage outlet repairs should be performed by a qualified electrician or gate technician.

Professional Advisory

Transformer replacement should be done with safe power handling. If the outlet, plug, or wiring is damaged, correct that condition before reconnecting the gate operator.

Product Questions and Answers

What voltage is the RB502 transformer?

RB502 is a 14 volt AC transformer.

Which models commonly use RB502?

It is commonly listed for Mighty Mule 362-D, 402, 700/1000 references, and GTO/Linear PRO 1000/1200 applications where specified.

Is RB502 interchangeable with RB570?

No. RB502 is 14VAC and RB570 is 18VAC 40VA. Use the transformer specified for the operator.

Will this fix a gate battery that will not charge?

It can if the transformer has failed, but the battery, wiring, fuse, and board charging circuit should also be checked.

Is RB502 compatible with AQ250 or AQ251 boards?

Manufacturer notes indicate it is not compatible with AQ250 or AQ251 boards.