FEATURES
- External Indicator Lights
- Plug-In PowerPort Cards
- Switchable Priority
- Simplified Wiring
- Add-On Power Controls
- Fully Enclosed Snap-Out
- Relays
- Compact Design
- Fuse Protected
- 100% Factory Tested
- Isolated End Switch
- Expandable to 20 Zones
- Contractor Friendly PC
- Board Layout
- Universal Thermostat
- Compatibility
- UL Approved
- 24 volt Power Input or Output Terminal
- Extended 3 Year Warranty
- Made in the USA
SIMPLY ADVANCED!
Taco Switching Relays combine clearly labeled PC board layouts with advanced features that allow for total system customization. Whether using basic priority switching, plug-in PowerPort cards or add-on power 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 listed, use standard “ice cube” replaceable relays and are compatible with conventional and programmable thermostats. For those larger jobs, the switching relays can be expanded up to 20 zones with priority.
Advanced Features
With the exclusive Taco PowerPort Plug-In Cards, such features as post purge, priority protection and pump exercise can be added with ease. Any expandable switching relay can also interface with the boiler reset control and injection mixing add-on power controls. Mix-and-match to customize the system.
External Diagnostics
It’s no longer necessary to remove the box cover to troubleshoot the system. External visible indicator lights show full functionality of all the products wired to the switching relay. The green light indicates power is connected. When the thermostat calls for heat, both the appropriate circulator and red indicator light is energized.
Switching Relays
Dimensions of Enclosure
Product Number Number of Zones Maximum Combined Load Transformer Voltage Width Height Depth
SR501 1 Zone 7.2 amps 120 VAC Input 4-1/4″ 5-1/4″ 2-3/4″
SR502 2 w/ Priority 15 amps 120 VAC Input 10-1/4″ 6-3/4″ 2-3/4″
SR503 3 w/ Priority 15 amps 120 VAC Input 10-1/4″ 6-3/4″ 2-3/4″
SR504 4 w/ Priority 20 amps 120 VAC Input 10-1/4″ 6-3/4″ 2-3/4″
SR506 6 w/ Priority 20 amps 120 VAC Input 11-3/4″ 7-1/2″ 3″
Switching Relays with PowerPort Options
Dimensions of Enclosure
Product Number Number of Zones Power Ports Maximum Combined Load Transformer Voltage Width Height Depth
SR503-EXP 3 w/ Priority 3 20 amps 120 VAC Input 10-1/4″ 6-3/4″ 2-3/4″
SR504-EXP 4 w/ Priority 3 20 amps 120 VAC Input 10-1/4″ 6-3/4″ 2-3/4″
SR506-EXP 6 w/ Priority 3 20 amps 120 VAC Input 11-3/4″ 7-1/2″ 3″
All Switching Relays are relay type DPST, have a thermostat current of.18, and have a single phase motor rating per zone of 1/3 hp (7.2 A) @ 120 VAC
