The Q45P pH system combines a microprocessor-based monitor/analyzer with a rugged industrial sensor. Sensor components are made of PEEK thermoplastic. Other sensor features include dual o-ring seals, replaceable saltbridge and custom double-shielded cable. The monitor is easily converted from a loop-powered device into a line-powered controller with relays, or battery-powered portable unit, using optional plug-in cards. All systems include full electronic isolation and sensor diagnostics. Quantum Analytical Instruments Inc.