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TACO SR503-EXP-4 Image 1

TACO SR503-EXP-4 3 ZONE EXPANDABLE SWITCHING RELAY WITH PRIORITY

MFR Part #: SR503-EXP-4
SKU #: 1218345
Brand: Taco® Comfort Solutions™
UPC: 687752857597
Please note this item is discontinued (order fulfillment will depend on stock availability): Taco® SR503-EXP-4 SR Expandable Switching Relay, 120 VAC, 20 A, DPDT Contact, 120 VAC V Coil, Domestic
3 Years
Instruction Sheet
Cold Start Boiler, Tankless Coil Boiler
UL and CSA Approved|UL Listed
Inventory Not Available

Taco®, SR503-EXP-4, Switching Relay, Expandable, Series: SR, 120 VAC, 20 A, 1/3 hp Power, 60 Hz Frequency, 120 VAC Coil, DPDT Contact Form, Screw Hole Mounting, 240 deg F, 6-3/4 in H x 10-1/4 in W x 2-3/4 in D Dimensions, Domestic

Taco Switching Relays combine clearly labeled PC board layouts with advanced features that allow for total system customization. Whether using basic priority switching or the advanced features of the -EXP controls, the job is made easy. External indicator lights provide instant diagnostic feedback, making a snap of service calls or new installation start-ups. All switching relays are UL and CSA listed, use standard ice cube replaceable relays and are compatible with conventional and programmable thermostats. For larger jobs, switching relays can be expanded up to 20 zones with priority. With the exclusive Taco PowerPort Plug-In Cards, you can easily add such features as post purge, priority protection and pump exercise. Any expandable switching relay can also interface with the Boiler Reset Control and Injection Mixing Add-On Power Controls.

Product Details

Taco®, SR503-EXP-4, Switching Relay, Expandable, Series: SR, 120 VAC, 20 A, 1/3 hp Power, 60 Hz Frequency, 120 VAC Coil, DPDT Contact Form, Screw Hole Mounting, 240 deg F, 6-3/4 in H x 10-1/4 in W x 2-3/4 in D Dimensions, Domestic

Taco Switching Relays combine clearly labeled PC board layouts with advanced features that allow for total system customization. Whether using basic priority switching or the advanced features of the -EXP controls, the job is made easy. External indicator lights provide instant diagnostic feedback, making a snap of service calls or new installation start-ups. All switching relays are UL and CSA listed, use standard ice cube replaceable relays and are compatible with conventional and programmable thermostats. For larger jobs, switching relays can be expanded up to 20 zones with priority. With the exclusive Taco PowerPort Plug-In Cards, you can easily add such features as post purge, priority protection and pump exercise. Any expandable switching relay can also interface with the Boiler Reset Control and Injection Mixing Add-On Power Controls.

Attributes

Amperage Rating20 A
Coil Voltage120 VAC
Contact FormDPDT
Country Of OriginUS
Dimensions6-3/4 in H x 10-1/4 in W x 2-3/4 in D
Domestic/ImportDomestic
Frequency Rating60 Hz
Power Rating1/3 hp
SeriesSR
Temperature Rating240 deg F
TypeExpandable
Voltage Rating120 VAC
Mounting TypeScrew Hole

Features

  • External indicator lights
  • Fully enclosed snap-out relays
  • 24 V power input or output terminal
  • Front Diagnostic Lights
  • Switchable Priority
  • Simplified Wiring
  • Built-in Priority Protection
  • Compact Design
  • Fuse Protected
  • 100% Factory Tested
  • Isolated End Switch
  • Contractor Friendly PC Board Layout
  • Universal Thermostat Compatibility
  • 24 Volt Power Output for hard wired thermostats
  • Field Replaceable Transformer
  • Add-on Power Control Plug
  • Built-in, Post Purge and Pump Exercise Functions
  • Switchable Primary Circulator Output
  • Two boiler contacts, utilizes full functionality of Mod-Con boilers
  • Interface with -EXP Zone Valve Controls