The SPM Series from the ATC Diversified Electronics Div., Marsh Bellofram Corp., Newell, WV, is a dual-function alarm and relay designed to monitor the shaft seal and stator temperature of a submersible pump motor, providing early warning of machinery failure. The device is designed to operate from a 120 VAC supply, with reliable operation over 10 million continuous duty cycles, and detects leaks by either resistive float switch or a pair of conductive probes installed in the seal cavity. Over-temperature is detected by a NC low-temperature switch mounted on the stator, with status LEDs for normal, leak, and over-temperature conditions. An incorporated bi-stable relay can retain its position during power failures or energy surges; the relay automatically resets following leakage detection.
Marsh Bellofram Corp.