Is there a connector kit supplied with the unit?
Yes, there is a connector kit supplied with the unit.
What are the commercial specifications?
These commercial 12, 20, 24 pole hermetically sealed bifurcated relays have gold plated relay contacts that are rated up to 2amp resistive load rating at 28vdc. Each relay is independently switched through their appropriate coil pins.
What is the pin out difference between the SR54 and the SR54-1?
They are the same Pin for Pin, and package the same as the SR54. The SR54 model became obsolete and was replaced by the SR54-1 version
What is the SR 54‑1 Switching Relay?
The SR 54‑1 is a 20‑pole, aircraft-grade switching relay module built with five hermetically sealed bifurcated relays and gold‑plated contacts. It’s designed to upgrade GPS, HSI/CDI, and other avionics systems by reliably switching multiple signal lines simultaneously.
What voltage does the SR 54‑1 require and what’s its current rating?
It operates on standard 28 VDC power; the coils draw approximately 120 mA each, and relay contacts are rated for up to 2 A resistive load.
Does the relay support automatic switching of LOC signals?
Yes — it features built-in reversionary circuitry. When the K6 relay is activated, all relays energize to ensure LOC steering is automatically displayed on your HSI.
What are the physical and environmental specifications?
The unit weighs about 0.26 lb and measures 3.92″ × 3.5″ × 0.82″. It operates safely in environments from –20 °C to +55 °C and up to 50,000 ft altitude.
Is the SR 54‑1 certified?
FAA-PMA approval is currently pending, allowing future installation in certified aircraft without requiring field approval.
What are typical applications for the SR 54‑1?
Ideal for systems where GPS or other LRNS share CDI/HSI with VOR/LOC. It switches resolver/steering lines and ensures reliable navigation signal routing during ILS or power loss transitions.
What are the benefits of choosing this relay unit?
Compact and lightweight, the SR 54‑1 ensures dependable, simultaneous multi-channel switching through sealed, gold-plated contacts—reducing wear and boosting avionics reliability.
How do I install and maintain the SR 54‑1?
Installation follows Sandia’s MARC‑70 wiring and pin‑out diagrams (available in the service manual). Maintenance is minimal—just check electrical connections during regular avionics inspections.
Where can I purchase the SR 54‑1 or get technical support?
The relay can be ordered directly through Sandia or authorized distributors. Technical documentation and installation guides are available on Sandia’s website under Service Manuals.
Are there smaller or larger relay modules available in the same series?
Yes—Sandia also offers the SR 34‑1 (12‑pole) and SR 64‑1 (24‑pole) modules. All share the same sealed, gold-contact, reliable design.
