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Robertshaw Class 2 Transformer: 40 VA Power Rating, 120V AC, 24V AC, Primary Fuse - Open Class 2 Transformers
RobertshawOpen Class 2 Transformers

Robertshaw Class 2 Transformer: 40 VA Power Rating, 120V AC, 24V AC, Primary Fuse

The ROBERTSHAW Class 2 Transformer is an open-style transformer with a 40 VA power rating, designed for plate mounting. It features a 120V AC primary input and a 24V AC secondary output, with wire lead connections on…

SKU 3G-OTH-46915

Brand
Robertshaw
Item
Class 2 Transformer: 40 VA Power Rating, 120V AC, 24V AC, Primary Fuse
Category
Open Class 2 Transformers
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Technical Specifications

Robertshaw
Manufacturer Part Number
620-403
Type
Primary Fuse, Foot/Plate
AC
120V
Mounting
Plate
Input Voltage
120V AC
Output Voltage
24V AC
Connection - Primary
Wire Lead
Connection - Secondary
Wire Lead
View Full Spec Sheet

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Robertshaw Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The ROBERTSHAW Class 2 Transformer is an open-style transformer with a 40 VA power rating, designed for plate mounting. It features a 120V AC primary input and a 24V AC secondary output, with wire lead connections on both the primary and secondary sides. This model (MPN 620-403) includes a primary fuse for protection.

Frequently Asked Questions

What is the ROBERTSHAW Class 2 Transformer used for?

The ROBERTSHAW Class 2 Transformer (MPN 620-403) steps down 120V AC primary power to 24V AC secondary power for low-voltage control circuits in HVAC systems, boilers, and industrial automation. Its 40 VA rating suits thermostats, relays, and zone valves.

What are the specifications of the ROBERTSHAW Class 2 Transformer?

This open-style transformer has a 40 VA power rating, 120V AC input, and 24V AC output. It features wire lead connections on both primary and secondary sides, plate mounting, and a primary fuse for protection. The brand is ROBERTSHAW, MPN 620-403.

Where to buy the ROBERTSHAW Class 2 Transformer worldwide?

3G Electric supplies the ROBERTSHAW Class 2 Transformer (MPN 620-403) worldwide. As a global industrial distributor, we handle full logistics, customs clearance, and delivery to your site. Contact us for availability and lead time.

How to install a ROBERTSHAW Class 2 Transformer?

Mount the transformer securely on a plate using the foot/plate design. Connect the primary wire leads to a 120V AC source and the secondary leads to the 24V AC load. Ensure the primary fuse is correctly rated. Follow local electrical codes and disconnect power before installation.

Used in

Common applications for Robertshaw
Commercial HVAC — Robertshaw RS10420T digital WiFi thermostat for programmable heat and cool control in office buildings
Furnace ignition — Robertshaw 41-230 universal hot surface ignitor for silicon carbide replacement in residential and light commercial furnaces
Airflow monitoring — Robertshaw 2374-509 adjustable air pressure switch for draft sensing in industrial burner systems
Gas-fired equipment — Robertshaw 1820-009 universal pilot assembly with thermopile for natural gas or LP water heaters and boilers
Vibration protection — Robertshaw 366A0 mechanical vibration switch for pump and compressor monitoring in industrial plants
OEM replacement — Robertshaw 41-428N direct spark igniter for Trane HVAC equipment requiring silicon nitride ignitors

Robertshaw Products

3G Electric supplies Robertshaw open class 2 transformers. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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