User Guide

1 INTRODUCTION
1.1 Description of Unit
Thank you for purchasing Eutech’s ¼ DIN alpha-1000 series Dissolved Oxygen
process controller. This unit is used for measuring either in % saturation, mg/l or
ppm, one at a time, and the operational mode is switchable from the menu. You can
use this unit to measure Dissolved Oxygen with limit or proportional control. This
controller has many user-friendly and safety features which include:
• Menu-driven program that simplifies set-up
• Built-in Memory backup to ensure that calibration data and other information
are not erased if power supply fails
• Push-button one-/two-point calibration and electrode offset adjustment
from the keypad
• Automatic temperature compensation (ATC)
• Manual temperature compensation with independent setting for calibration
and process temperature
• 0 to 1999 second time delay adjustment on all relays – minimise false alarms
• Separately adjustable high and low set point hysteresis (dead bands)
prevent chattering of relays around the set points
• Three control modes: limit control, proportional pulse length or proportional
pulse frequency
• Large dual display LCD for easy reading with clear multiple annunciators,
alarm status and operational message annunciators
• Two switching contacts as set-point triggering relays and an alarm output
relay
• Separate alarm relay alerts you when set points have exceeded the limits and
if the Pt100 wires are broken or disconnected during the ATC function
• Hold function freezes output current (0/4...20mA) and releases control relays
• LED indicators signal control activities to monitor controller status from a
distance
• Protection against electromagnetic interference - galvanically isolated 0/4 -
20mA output provides safety for data logging and control purposes
1.2
Applications
Use this controller in panel mounted enclosures for applications such as water
treatment and monitoring, galvanic-decontamination, chemical processing, food
processing, clean or waste water control and neutralization process.