R-K Electronics, Inc. Protection Relays & Systems STR-24D-B

The STR is a seal and temperature status relay designed to monitor submersible pump motor integrity by detecting seal leakage or open temperature sensors. It supports 24VDC supply voltage and features pluggable terminal blocks for connections. The device offers 1-input or 2-input operation modes, with adjustable seal resistance trip points from 5kΩ to 200kΩ and fixed temperature fault thresholds at 330Ω and 1,500Ω. It provides two SPDT relay outputs rated at 5A at 120VAC, 6A at 277VAC, and 5A at 30VDC. Mounting is surface mount with epoxy fill, and operating ambient temperatures range from -40°C to 65°C for tabs and -40°C to 60°C for terminal blocks. A 16-character, 2-line backlit display is included for status indication.