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Robertshaw Class 2 Transformer: 75 VA Power Rating, 120V AC/208V AC/240V AC/480V AC - Open Class 2 Transformers
RobertshawOpen Class 2 Transformers

Robertshaw Class 2 Transformer: 75 VA Power Rating, 120V AC/208V AC/240V AC/480V AC

The ROBERTSHAW Class 2 Transformer (MPN 620-503) is an open Class 2 transformer with a 75 VA power rating. It features a plate mounting style, 120V AC input voltage, and 24V AC output voltage, with wire lead…

SKU 3G-OTH-49311

Brand
Robertshaw
Item
Class 2 Transformer: 75 VA Power Rating, 120V AC/208V AC/240V AC/480V AC
Category
Open Class 2 Transformers
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Technical Specifications

Robertshaw
Manufacturer Part Number
620-503
AC
24V
Mounting
Plate
Input Voltage
120V AC
Output Voltage
24V AC
Connection - Primary
Wire Lead
Connection - Secondary
Wire Lead
AC/208V AC/240V AC/480V AC
120V
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Robertshaw Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The ROBERTSHAW Class 2 Transformer (MPN 620-503) is an open Class 2 transformer with a 75 VA power rating. It features a plate mounting style, 120V AC input voltage, and 24V AC output voltage, with wire lead connections for both primary and secondary sides.

Frequently Asked Questions

What is a Robertshaw Class 2 transformer used for?

A Robertshaw Class 2 transformer steps down line voltage to 24V AC for powering low-voltage controls, relays, and thermostats in HVAC, burner management, and industrial automation systems. It supplies 75 VA to multiple loads safely.

What are the specifications of the Robertshaw 620-503 transformer?

The Robertshaw 620-503 is a 75 VA open Class 2 transformer with 120V AC input and 24V AC output. It has wire lead connections on both primary and secondary sides and a plate mounting style. It also accepts 208V, 240V, and 480V AC inputs.

Where to buy a Robertshaw 620-503 transformer worldwide?

3G Electric supplies the Robertshaw 620-503 Class 2 transformer to customers worldwide. We handle full logistics, customs clearance, and delivery to your site. Contact us for a quote and lead time on this and other industrial control components.

How to install a Robertshaw Class 2 transformer?

Mount the transformer securely using the plate mounting holes. Connect primary wire leads to the correct input voltage (120V, 208V, 240V, or 480V AC) per local codes. Connect secondary leads to the 24V AC load. Ensure the total VA draw does not exceed 75 VA.

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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