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TACOZone-Switching Relays

TACO Zone Switching Relay: Switching, 3 with Priority Zones, 0 Power Port Slots

The TACO SR503-5 is a zone-switching relay with 3 zones with priority, operating on a 120V AC primary supply. It supports a full-load amperage (FLA) of 20 A at 120V AC. This switching relay is designed for zone…

SKU 3G-OTH-67263

Brand
TACO
Item
Zone Switching Relay: Switching, 3 with Priority Zones, 0 Power Port Slots
Category
Zone-Switching Relays
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Technical Specifications

TACO
Manufacturer Part Number
SR503-5
Type
3 with Priority Zones
AC Primary
120V
Number of Zones
3 with Priority
Power Port Slots
0
Current Ratings @ Voltages
FLA: 20 A @ 120V AC
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TACO Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The TACO SR503-5 is a zone-switching relay with 3 zones with priority, operating on a 120V AC primary supply. It supports a full-load amperage (FLA) of 20 A at 120V AC. This switching relay is designed for zone control in hydronic heating systems.

Used in

Common applications for TACO
Hydronic heating systems — TACO 007 series circulator pumps for residential boiler water circulation.
Commercial HVAC — TACO 2400-60-3P inline pump for chilled water loops in large buildings.
Industrial process cooling — TACO 1630EAE10132096 pump for high-flow (110 gpm) cooling applications.
Zone control in radiant floor heating — TACO V075T2G2ZA024Q4A2 zone valve for regulating flow to individual zones.
Pump replacement and maintenance — TACO 007-045RP cartridge assembly for servicing existing 007 series pumps.
Piping connections in hydronic systems — TACO 110-251F-1 flange for joining pumps to pipework.

TACO Products

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

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