Thermo Fisher Scientific Alpha pH 2000D - Manual (Page 8)

2 Product Description
2.1 Description of Unit
The Alpha pH 2000D is used for measuring pH and temperature values. The pH values can be measured using industrial
differential & combination pH sensors. The temperature values can be measured using 2-wire / 3-wire NTC300 thermistor.
The transmitter is available in a wall mounting enclosure. The controller / transmitter can be used for applications such as
water treatment and monitoring, galvanic-decontamination, chemical processing, food processing, clean or wastewater
control and neutralization processes.
This transmitter has many user-friendly and safety features which include:
• Push-button for calibration and sensor offset adjustment from the keypad.
• Built-in non-volatile memory to ensure that calibration and other information are not erased if power supply fails.
• Menu-driven program that simplifies set-up.
• Automatic temperature compensation (ATC).
• Manual temperature compensation setting without the ATC probe, with independent setting for calibration and process
temperature.
• Two galvanically isolated current outputs 0/4...20mA.
• Two switching contacts as set-point relays.
• 0 to 2000 seconds time delay adjustment on all relays – minimizes false alarms.
• Separately adjustable high and low set-point hysteresis (dead bands) prevent chattering of relays around the set points.
• Three control modes: limit controller, P controller and PI controller (P/PI controller as pulse length or pulse frequency).
• Large dual display LCD for easy reading with clear multiple annunciators, alarm status, operational and error messages.
• Separate alarm relay alerting you to set point limits exceeded for a certain time and if the NTC300 thermistor wires are
broken or disconnected during the ATC function.
• Wash relay.
• Hold function to freeze output current (0/4...20mA) and release control relays.
• LED indicators signal control activities to visually monitor transmitter status from a distance.
• Protection against electromagnetic interference.
• Back lit and UV light protected LC display.
- 3 -