Thermo Fisher Scientific Alpha pH 2000 - Manual (Page 10)

2 PRODUCT DESCRIPTION
2.1 Description of unit
The Alpha pH 2000 is used for measuring pH or ORP and temperature
values. The pH or ORP values can be measured using proportional or limit
control. The controller is available in two versions, one for panel mounting
and one for wall mounting in an enclosure. The controller 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 controller has many user-friendly and safety features which include:
• Menu-driven program that simplifies set-up.
• Built-in non-volatile memory to ensure that calibration and other
information are not erased if power supply fails.
• Push-button for calibration and electrode offset adjustment from the
keypad.
• 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
• 0 to 1999 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.
• Asymmetrical/symmetrical input for pH/ORP mode of operation.
• 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.
• Two switching contacts as set-point relays.
• Separate alarm relay alerting you to set point limits exceeded for a certain
time and if the Pt100/Pt1000 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