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3G Electric
Robertshaw Open Class 2 Transformer - Open Class 2 Transformers
RobertshawOpen Class 2 Transformers

Robertshaw Open Class 2 Transformer

<p>The Robertshaw Open Class 2 Transformer (620-503) is a reliable power conversion solution for HVAC and industrial control applications. This model delivers 75 VA with a 120V AC primary input and a 24V AC secondary…

SKU 3G-OTH-49311

Also listed as: 620503 · 620 503

Brand
Robertshaw
Item
Open Class 2 Transformer
Part Number
620-503
Category
Open Class 2 Transformers
Available to Order
Also known as:620-503Robertshaw
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Technical specs
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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

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

Technical Documents

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

Product Description

<p>The Robertshaw Open Class 2 Transformer (620-503) is a reliable power conversion solution for HVAC and industrial control applications. This model delivers 75 VA with a 120V AC primary input and a 24V AC secondary output, making it suitable for powering low-voltage control circuits. It features a plate mount design and wire lead connections for both primary and secondary sides, simplifying installation in control panels and equipment.</p><p>As a Singapore-based supplier, 3G Electric offers this transformer with worldwide shipping. For procurement buyers in Singapore, we provide SGD quotes on request and handle GST for local purchases. Enjoy fast delivery across Singapore and Southeast Asia, ensuring your projects stay on schedule.</p>

Frequently Asked Questions

What are the input and output voltages of the Robertshaw 620-503 transformer?

The input voltage is 120V AC, and the output voltage is 24V AC.

How is the transformer mounted and connected?

It is plate mounted, and both primary and secondary connections are wire leads.

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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