Cole-Parmer online controllers offer features found in more expensive models. Graphic LCD simultaneously displays measurement, temperature, electrode status, relay status, and transmitter current output. Calibration data is stored in memory; making the unit ready for measurement. Password protection, RS-485 for remote access, and the isolated and reversible 4 to 20 mA output offer extended data options with security.

The pH 500 (05802-16) controller has one isolated and reversible 4 to 20 mA output and five programmable on/off relays: four for pH and one for temperature--ideal for high/low control to activate an alarm, a pump, or another device. ATC element is a 10 kilohm thermistor.