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Robertshaw 620-404 Open Class 2 Transformer - Open Class 2 Transformers
RobertshawOpen Class 2 Transformers

Robertshaw 620-404 Open Class 2 Transformer

The ROBERTSHAW Class 2 Transformer is an open-style transformer with a 40 VA power rating, designed for plate mounting. It features a 208V AC primary input and a 24V AC secondary output, with wire lead connections on…

SKU 3G-OTH-48953

Also listed as: 620404 · 620 404

Brand
Robertshaw
Item
620-404 Open Class 2 Transformer
Part Number
620-404
Category
Open Class 2 Transformers
Available to Order
Also known as:620-404Robertshaw
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Technical Specifications

Robertshaw
Manufacturer Part Number
620-404
Type
Primary Fuse, Wire Lead
AC
24V
Mounting
Plate
AC/240V AC
208V
Input Voltage
208V AC
Output Voltage
24V AC
Connection - Primary
Wire Lead
Connection - Secondary
Wire Lead

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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 208V AC primary input and a 24V AC secondary output, with wire lead connections on both the primary and secondary sides. This model, part number 620-404, includes a primary fuse for protection.

Frequently Asked Questions

What is the Robertshaw Class 2 Transformer used for?

The Robertshaw Class 2 Transformer (MPN 620-404) steps down 208V AC input to 24V AC output for powering low-voltage controls in HVAC systems, boilers, and industrial automation. Its 40 VA rating suits thermostats, relays, and damper actuators in commercial and light industrial applications.

What are the specifications of the Robertshaw Class 2 Transformer 620-404?

This Robertshaw open-style transformer has a 40 VA power rating, 208V AC primary input, and 24V AC secondary output. It features wire lead connections on both sides, plate mounting, and a primary fuse for protection. The manufacturer part number is 620-404.

Where to buy the Robertshaw Class 2 Transformer worldwide?

3G Electric supplies the Robertshaw Class 2 Transformer 620-404 worldwide. As a global industrial distributor, we handle full logistics, customs clearance, and delivery to your site. Contact us for availability and lead time; we source and deliver this transformer to any country.

How to install the Robertshaw Class 2 Transformer?

Mount the Robertshaw transformer securely on a plate using the provided mounting holes. Connect the primary wire leads to a 208V AC supply 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
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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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Open Class 2 transformer with foot mounting. Input voltage 240V AC; output voltage 2.5V AC. Wire lead connections on primary and secondary. Commonly used to step down line voltage for low-voltage control circuits in HVAC and industrial equipment
Robertshaw
Open Class 2 transformer with foot mounting. Input voltage 240V AC; output voltage 2.5V AC. Wire lead connections on primary and secondary. Commonly used to step down line voltage for low-voltage control circuits in HVAC and industrial equipment

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