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SQUARE D Thermal Unit: 20 Trip Class, A.78 - Electrical
SQUAREElectrical

SQUARE D Thermal Unit: 20 Trip Class, A.78

SQUARE Electrical.

SKU 3G-OTH-42195

Also listed as: A78 · A 78 · A-78

Brand
SQUARE
Item
D Thermal Unit: 20 Trip Class, A.78
Category
Electrical
UNSPSC
39121029 — Isolation transformer
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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

SQUARE
Manufacturer Part Number
A.78

Technical Documents

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

Product Description

SQUARE Electrical.

Frequently Asked Questions

What is the SQUARE D Thermal Unit A.78 used for?

The SQUARE D Thermal Unit A.78 is an overload protection device for motor starters. It protects motors from overheating by tripping the circuit when current exceeds a safe level. Common in industrial automation, HVAC, and pump systems, it ensures equipment longevity and safety in continuous-duty applications.

What are the specifications of the SQUARE D Thermal Unit A.78?

The SQUARE D Thermal Unit A.78 has a trip class of 20 and a manufacturer part number A.78. It is designed for use with SQUARE D motor starters and overload relays. The unit provides precise thermal protection based on motor current and ambient temperature, ensuring reliable operation in industrial environments.

Where to buy SQUARE D Thermal Unit A.78 worldwide?

You can source the SQUARE D Thermal Unit A.78 through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations. Contact us for availability and lead time; we supply genuine SQUARE D components for your motor protection needs.

How to select the correct SQUARE D Thermal Unit for a motor?

Select the SQUARE D Thermal Unit by matching the motor full-load current (FLC) to the unit's trip range. The A.78 is a 20 trip class unit, suitable for standard motor starting. Consult the motor nameplate and SQUARE D selection tables to ensure proper overload protection. Always verify ambient temperature compensation for accurate performance.

Used in

Common applications for SQUARE
Industrial power distribution — Square D HU362AWC non-fusible safety switch for disconnecting three-phase loads up to 60 A.
Busway branch circuits — Square D PQ4203G fusible bus plug for overcurrent protection in I-Line busway systems.
Panelboard surge protection — Square D HL4IMA24C SPD for transient voltage suppression in 277/480V AC wye systems.
Power distribution in control panels — Square D 9080LBA263106 open distribution block for splitting 400 kcmil conductors.
Machine control stations — Square D 9001BG303 push-button station for open/close/stop operations in industrial machinery.
Motor starting and protection — Square D 8536SBG2V02H30S NEMA starter for non-reversing three-phase motor control up to 18 A.

SQUARE Products

3G Electric supplies SQUARE electrical. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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Compatible alternatives & equivalents

Cross-referenced by specification & description
HUBBELL Receptacle: Quad, 5-20, Brown, 125V AC, 20 A, 2 Pole / 3 Wire (MPN HBL420)
HUBBELL
HUBBELL Receptacle: Quad, 5-20, Brown, 125V AC, 20 A, 2 Pole / 3 Wire (MPN HBL420)
HUBBELL Receptacle: Quad, 5-20, Ivory, 125V AC, 20 A, 2 Pole / 3 Wire (MPN HBL420I)
HUBBELL
HUBBELL Receptacle: Quad, 5-20, Ivory, 125V AC, 20 A, 2 Pole / 3 Wire (MPN HBL420I)
HUBBELL Receptacle: Quad, 5-20, Ivory, 125V AC, 20 A, 2 Pole / 3 Wire (MPN HBL420IS)
HUBBELL
HUBBELL Receptacle: Quad, 5-20, Ivory, 125V AC, 20 A, 2 Pole / 3 Wire (MPN HBL420IS)
HUBBELL Receptacle: Quad, 5-20, Blue, 125V AC, 20 A, 2 Pole / 3 Wire (MPN HBL420S)
HUBBELL
HUBBELL Receptacle: Quad, 5-20, Blue, 125V AC, 20 A, 2 Pole / 3 Wire (MPN HBL420S)
HUBBELL Receptacle: Duplex, 5-20, Brown, 125V AC, 20 A, 2 Pole / 3 Wire (MPN BR20STTR)
HUBBELL
HUBBELL Receptacle: Duplex, 5-20, Brown, 125V AC, 20 A, 2 Pole / 3 Wire (MPN BR20STTR)
HUBBELL Receptacle: Duplex, 5-20, Brown, 125V AC, 20 A, 2 Pole / 3 Wire (MPN HBL5352)
HUBBELL
HUBBELL Receptacle: Duplex, 5-20, Brown, 125V AC, 20 A, 2 Pole / 3 Wire (MPN HBL5352)

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